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Climate Change Vulnerability Assessment for Colorado Bureau of Land Management

Authors:
Karin Decker at Colorado State University
Karin Decker
Lee Grunau at Colorado State University
Lee Grunau
Jill Handwerk at Colorado State University
Jill Handwerk
Jeremy L. Siemers at Colorado State University
Jeremy L. Siemers
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Abstract

The Colorado Natural Heritage Program conducted climate change vulnerability assessments of plant and animal species, and terrestrial and freshwater ecosystems (“targets”) within a time frame of mid-21st century. Our assessments 1) evaluate the potential impact of future climate conditions on both species and ecosystems by identifying the degree of change expected between current and future climate conditions within the Colorado range of the target, and 2) address the potential impact of non-climate factors that can affect the resilience of the target to climate change, or which are likely to have a greater impact due to climate change. Climate change vulnerability assessments are intended to help BLM managers identify areas where action may mitigate the effects of climate change, recognize potential novel conditions that may require additional analysis, and characterize uncertainties inherent in the process.
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December2015
ClimateChangeVulnerability
AssessmentforColorado
BureauofLandManagement
CNHP’smissionistopreservethenaturaldiversityoflifebycontributingtheessentialscientific
foundationthatleadstolastingconservationofColorado'sbiologicalwealth.
ColoradoNaturalHeritageProgram
WarnerCollegeofNaturalResources
ColoradoStateUniversity
1475CampusDelivery
FortCollins,CO80523
(970)491‐7331
ReportPreparedfor:
BureauofLandManagement
ColoradoStateOffice
2850YoungfieldStreet
Lakewood,Colorado80215
RecommendedCitation:
ColoradoNaturalHeritageProgram[CNHP].2015.ClimateChangeVulnerabilityAssessmentfor
ColoradoBureauofLandManagement.K.Decker,L.Grunau,J.Handwerk,andJ.Siemers,editors.
ColoradoNaturalHeritageProgram,ColoradoStateUniversity,FortCollins,Colorado.
Individualchaptersmaybecitedassuggestedbelow.
Frontcover:KnowlesCanyon,photo©PeggyLyon.
Climate Change Vulnerability
Assessment for Colorado Bureau
of Land Management
ColoradoNaturalHeritageProgram
WarnerCollegeofNaturalResources
ColoradoStateUniversity
FortCollins,Colorado80523


December2015
iiColoradoNaturalHeritageProgram©2015
EXECUTIVE SUMMARY
TheColoradoofficeoftheBureauofLandManagement(BLM),whichadministers8.4millionacres
ofColorado’ssurfaceacres,andmorethan29millionacresofsub‐surfacemineralestate,hasbeen
chargedwithdevelopingaclimateadaptationstrategyforBLMlandswithinthestate.The
assessmentspresentedhereinpresentastatewideperspectiveonthepotentialfutureinfluencesof
achangingclimateonspeciesandecosystemsofparticularimportancetotheBLM,withthegoalof
facilitatingdevelopmentofthebestpossibleclimateadaptationstrategiestomeetfuture
conditions.
TheColoradoNaturalHeritageProgramconductedclimatechangevulnerabilityassessmentsof
plantandanimalspecies,andterrestrialandfreshwaterecosystems(“targets”)withinatimeframe
ofmid‐21stcentury.Ourassessments1)evaluatethepotentialimpactoffutureclimateconditions
onbothspeciesandecosystemsbyidentifyingthedegreeofchangeexpectedbetweencurrentand
futureclimateconditionswithintheColoradorangeofthetarget,and2)addressthepotential
impactofnon‐climatefactorsthatcanaffecttheresilienceofthetargettoclimatechange,orwhich
arelikelytohaveagreaterimpactduetoclimatechange.Climatechangevulnerabilityassessments
arenotanenduntothemselves,butareintendedtohelpBLMmanagersidentifyareaswhereaction
maymitigatetheeffectsofclimatechange,recognizepotentialnovelconditionsthatmayrequire
additionalanalysis,andcharacterizeuncertaintiesinherentintheprocess.
Ecosystems
Sixteenterrestrialecosystemtypesandsixfreshwaterecosystemgroupswereassessedundera
highradiativeforcingscenario(RCP8.5)fortheirrelativevulnerabilitybymid‐century.Terrestrial
typesincludedsixforestorwoodlandtypes,fourshrublandtypes,fourherbaceousorgrassland
types,andriparianandwetlandareas.Fourterrestrialtypes(pinyon‐juniperwoodland,shortgrass
prairie,andriparianandwetlandareasoftheeasternplains)wererankedwithhighvulnerability,
andasingletype(riparianwoodlandandshrublandoflowerelevationwestslopeareas)was
rankedwithveryhighvulnerability.Mostterrestrialecosystemswererankedwithlowormoderate
vulnerabilitytotheeffectsofclimatechangebymid‐century.
Themajorityofterrestrialecosystemswereevaluatedascurrentlyhavinglowtomoderate
resiliencetoclimateimpacts.Actionsthatincreaseecosystemresilienceandenhancetheadaptive
capacityofthesetargetswillcushiontheirvulnerabilitytochangingclimateconditions,andshould
beaprimaryfocusofmanagementefforts.Forforestandwoodlandecosystems,adaptationactions
arelikelytofocusondisturbancefactorssuchasfireandinsectoutbreak,whileforshrublandand
herbaceousecosystems,reducingtheimpactsofanthropogenicfragmentationanddisturbanceis
centraltoadaptationmanagement.
Freshwaterecosystems(streams,rivers,lakes,andreservoirs)wereevaluatedinrelationtoa
modeledtransitionzonebetweenwarmandcool‐tocold‐waterhabitatsthatcomparedcurrent
ClimateChangeVulnerabilityAssessmentforColoradoBLMiii
reachextentineachzonetowhatcouldbeexpectedunderwarmerfutureconditions.Resultswere
summarizedbythreeregions(easternplains,mountain,andwesternvalleys).Overallvulnerability
offreshwaterecosystemswasnoticeablyhigherthanforterrestrialtypes.Fouroftheevaluated
freshwaterecosystems,primarilythoseoflowerelevations,hadvulnerabilityranksofhighorvery
high.Onlystreamsofhigherelevationswereconsideredtohavelowvulnerability.
Nearlyallfreshwaterecosystemshavemoderatetohighexposuretopotentialimpactsfromclimate
change,andgenerallymoderatelevelsofresilienceoradaptivecapacity.Asaresult,mostofthese
typeswillremainmoderatelyvulnerableatbest,evenunderconditionsofimprovedresilience.
Actionsthatmaintainorincreasehydrologicconnectivityandreducenon‐climateimpactsarethe
primarymeansbywhichadaptivecapacityinfreshwaterecosystemscanbemaintainedor
increased.
Species
Ninety‐eightspecies(36animalsand62plants)wereevaluatedforvulnerabilitybymid‐century
usingtheNatureServeClimateChangeVulnerabilityIndex,underahighcumulativecarbon
emissionscenario(SRESA2).
Animalspeciesincludedfouramphibians,thirteenbirds,ninefish,oneinsect,sixmammals,and
threereptiles.Fivespecieswererankedasextremelyvulnerabletoclimatechange.Overall,42%of
theevaluatedanimalspecieswererankedwithhightoextremevulnerabilitytoclimatechangeby
mid‐century.Fish,inparticular,wererankedonthehightoextremelyvulnerableendoftherange;
othertaxonomicgroupsweregenerallymoreevenlydistributedbetweenpresumedstabletohighly
vulnerable.
Nearlyallofthevascularplantspecies(59of62)evaluatedwererankedwithextremelyhigh
vulnerabilitytoclimatechangebymid‐century,generallyduetotheirhighlyrestricted
distributions,naturalbarrierstomovementandrelativelylimiteddispersalabilityand/or
pollinatorspecificity.Restrictiontoaparticularphysiologicalhydrologicalniche,ortouncommon
geologicfeaturesandsubstratesalsotendtoincreasethevulnerabilityofmostofColorado’srare
plants.
Conclusions
Theclimatechangevulnerabilityassessmentspresentedhereinprovideabasicfoundationforthe
developmentofadaptationstrategiesgoingforward.Togetherwithclearlyarticulatedgoalsand
objectivesfortheconservationofimportantBLM‐managedresources,theinformationincludedin
theseassessmentshighlightingthepotentialimpactsofclimatechangeandspecies‐orecosystem‐
specifickeyvulnerabilitiescanbelinkedtospecificmanagementactionsthatareintendedto
addresschangingclimateconditions.
Itisimportanttorecognizethatspeciesassemblagesareverylikelytochangefromwhathasbeen
seeninthehistoricpast,sothattheinvestigationofshiftingdistributions,alteredecological
ivColoradoNaturalHeritageProgram©2015
functions,andcriticalthresholdsthataretiedtoawarmingclimatewillprovideessentialtoolsfor
adaptationstrategies.
Becauseearlieractionallowsforgreaterimpactandinfluenceonmanagementchallengesbothnow
andinthefuture,wesuggest:
UseofstructureddecisionmakingtechniquestofocusandclarifyBLMgoalsandobjectives
forclimatechangeadaptationtargets
Movingaheadwiththedevelopmentofadaptationstrategiesforkeyspeciesand
ecosystems
Prioritizingadaptationeffortsforspeciesandecosystems,takingintoconsiderationboth
thevulnerabilitylevelofthetarget,practicalcriteriaoftimeandresourceavailability,and
trade‐offsorconstraintsthatmaybepresent
Developingandimplementingmethodsformonitoringormeasuringtheresultsof
adaptationactions
Potentiallyrevisitingclimatechangevulnerabilityrankingsasnewinformationbecomes
availableoradditionalconcernsbecomeapparent.
ClimateChangeVulnerabilityAssessmentforColoradoBLMv
ACKNOWLEDGEMENTS
TheauthorswouldliketoacknowledgethegeneroussupportoftheBureauofLandManagement
ColoradoOffice,whoprovidedfundingforthiseffort.WethanktheBLMstaffwhosharedtheir
extensiveprofessionalexperienceandknowledgethroughouttheprocess.BruceRittenhouse
(BranchChief,NaturalResources),JayThompson(FisheryBiologist),andCarolDawson(Botanist)
actedascoordinatingliaisonsfortheproject.AdditionalBLMpersonnelwhoparticipatedinthe
reviewprocessincludeRobinSell(WildlifeBiologist),andBLMinternsPhilKreningandColleen
Sullivan.
MeganFriggens(ResearchEcologist)withtheUSDAForestServiceGrassland,Shrublandand
DesertEcosystemsProgramoftheRockyMountainResearchStationprovidedvaluablereviewand
inputregardingtheresiliencerankingsofforestandwoodlandecosystems,aswellasreviewofthe
documentasawhole.
WecontinuetoappreciatethehelpofJeffMorisetteandtheNorthCentralClimateScienceCenter
staff,especiallyColinandMarianTalbert,whoprovideduswithessentialtechnicaltoolsfor
accessingandusingclimateprojections.ShannonMcNeelyoftheNCCSCalsoprovidedfeedbackon
thepreliminaryresultsoftheassessment.
Finally,atCNHP,JoannaLemlyprovidedcriticalreviewandinformationaboutwetlandand
riparianhabitats,andRenéeRondeauprovidedadviceandreviewthroughouttheproject.Thank
youall.

viColoradoNaturalHeritageProgram©2015
TableofContents
ExecutiveSummary.......................................................................................................................................ii
Ecosystems................................................................................................................................................ii
Species.....................................................................................................................................................iii
Conclusions..............................................................................................................................................iii
Acknowledgements.......................................................................................................................................v
1INTRODUCTION............................................................................................................................... ...........1
2ECOSYSTEMS............................................................................................................................................19
3ANIMALS................................................................................................................................................173
4PLANTS...................................................................................................................................................325
AppendixA:CCVIScoringCategoryDefinitions........................................................................................542
AppendixB:FullCCVIScoringResults.......................................................................................................559
ClimateChangeVulnerabilityAssessmentforColoradoBLM1
1 INTRODUCTION
Author
KarinDecker
Recommendedchaptercitation:
Decker,K.2015.Introduction.Chapter1InColoradoNaturalHeritageProgram2015.ClimateChangeVulnerabilityAssessment
forColoradoBureauofLandManagement.K.Decker,L.Grunau,J.Handwerk,andJ.Siemers,editors.ColoradoNatural
HeritageProgram,ColoradoStateUniversity,FortCollins,Colorado.
2ColoradoNaturalHeritageProgram©2015
TableofContents–1Introduction
Background...................................................................................................................................................3
Studyarea.................................................................................................................................................4
Overview...............................................................................................................................................4
Generalclimate.....................................................................................................................................5
Geologyandsoils..................................................................................................................................5
Landownership.....................................................................................................................................5
Humaninfluenceonthelandscape......................................................................................................6
ClimateChangeVulnerabilityAssessment....................................................................................................8
Uncertaintyinclimatechangevulnerabilityassessment.........................................................................8
Comparingthevulnerabilityofecosystemsandspecies..........................................................................8
PreviousvulnerabilityassessmentsintheColoradoregion.....................................................................9
ClimatechangeinColorado....................................................................................................................15
LiteratureCited.......................................................................................................................................17
ListofFiguresandTables
Figure 1.1.Componentsofvulnerability(Glicketal.2011).........................................................................4
Figure 1.2.Historical(1990‐2014)Coloradostatewidetrendsfor(a)annualmeantemperature,(b)
annualprecipitation,and(c)PalmerDroughtSeverityIndex.Temperatureandprecipitationareshown
asdeparturefromthemeanofbaseperiod(1901‐2000).DataisfromNOAANationalCentersfor
EnvironmentalInformation:http://www.ncdc.noaa.gov/cag/data‐info...................................................16
Figure 1.3.Seasonalprojectedtemperature(a)andprecipitation(b)changesbymid‐21stcentury(2050;
centeredaround2035‐2064period)forColorado.....................................................................................17
Table 1.1.SummaryofclimatechangevulnerabilityassessmentsintheColoradoregionthathave
addressedhabitatsorspecies.
....................................................................................................................10

ClimateChangeVulnerabilityAssessmentforColoradoBLM3
BACKGROUND
TheColoradoofficeoftheBureauofLandManagement(BLM)hasbeenchargedwithdevelopinga
climateadaptationstrategyforBLMlandswithinthestate.Inordertoensurethebestpossible
adaptationstrategies,astatewideperspectiveonthepotentialfutureinfluencesofachanging
climateonspeciesandhabitatsisneeded.ToassisttheBLMinthiseffort,theColoradoNatural
HeritageProgram(CNHP)conductedaclimatechangevulnerabilityassessmentforpriorityspecies
andecosystemswithinatimeframeofmid‐21stcentury.
Thevulnerabilityassessmentisintendedtobepartofadynamic,iterative,multi‐scaleprocessthat
willfocusmanagementactionsonstrategiesthatareeffectiveunderbothcurrentandfuture
climates.ThecomponentsofvulnerabilityweredescribedbyGlicketal.(2011)andconsistof
projectedexposuretoclimatechange,sensitivityofthespeciesorecosystemtoexpectedchanges,
andtheadaptivecapacityofthespeciesorecosystemtorespondtochanges(Figure1.1).Although
thisdiagramisstraightforwardandconceptuallysimple,theindividualcomponentsofexposure,
sensitivity,andadaptivecapacitycanbedifficulttocalculatewithanyprecision.Uncertaintycomes
fromboththedegreeofvariationinthemanyclimateprojectionmodels,andfromthegapsinour
knowledgeofthetargetspeciesorhabitat.Inaddressingthesecomponents,wehopetoidentify
whichecosystemsaremostorleastvulnerabletoclimatechangeaswellasthetypeandspatial
patternofthemostsignificantimpacts.Thisinformationisexpectedtohelplandmanagersidentify
areaswhereactionmaymitigatetheeffectsofclimatechange,recognizepotentialnovelconditions
thatmayrequireadditionalanalysis,andcharacterizeuncertaintiesinherentintheprocess.
OurassessmentisalignedwithexistingandongoingvulnerabilityassessmentsforColoradospecies
andhabitatstomaximizetheefficiencyandeffectivenessofourwork,leveragedatadevelopment,
sharelessonslearned,andcoordinateexpertinputandinterpretation.TheseincludetheGunnison
BasinClimateWorkingGroup,SanJuanClimateInitiative,theStateWildlifeActionPlanrevision
andclimatechangevulnerabilityassessment,andtheColoradoRarePlantConservationInitiative.
Thisanalysisisbasedonarelativelyshorttemporalscale(i.e.,suitedtoagencyplanninghorizons
andattentivetouncertaintylevelsinprojectedclimatemodels)andtheuseofalimitedbut
representativesetofpotentialchangescenarios.
Ourobjectiveswereto:
1. Identifyplantandanimalspecies,andterrestrialandfreshwaterecosystemsofimportance
toBLMmanagementastargetsofouranalysis.
2. Evaluatethepotentialimpactoffutureclimateconditionsonbothspeciesandecosystems
byidentifyingthedegreeofclimatechangeexpectedbetweencurrentandfutureconditions
withintheColoradorangeofthetarget,andincorporatingscientificallydocumented
informationonspeciesorecosystemsresponsetoclimaticfactors.
3. Evaluatethepotentialimpactofnon‐climatefactorsparticulartoeachtargetthatcanaffect
theresilienceofthetargettoclimatechange,orwhicharelikelytohaveagreaterimpact
duetoclimatechange.
4. Producesummaryvulnerabilityrankingsforpriorityspeciesandecosystems.
4ColoradoNaturalHeritageProgram©2015
Figure 1.1.Componentsofvulnerability(Glicketal.2011).
Study area
Overview
Colorado’sboundariesencompasssome66.6millionacres,orover104,000squaremiles.Within
thisarea,thetypeandextentofnaturalvegetationisdeterminedbymanyfactors,including
elevation,climate,soils,disturbancepatterns,andtheecologicalhistoryofthelandscape.Colorado
spansthecontinentaldivideamidthehighestpeaksoftheSouthernRockyMountains.Asaresult,
thestate’stopologyiscomplex.Totheeastofthecontinentaldivide,theeasternplainsrisegently
attherateofabout10feetpermilefromelevationsof3,350‐3,650feetatthestate’seasternedge.
Althoughtheyappearcomparativelyflat,Colorado’seasternplainsboastlittle‐knowndramatic
rivercanyons,shaleoutcropsformingbuttesandscarps,sandystabilizeddunefields,andbasalt‐
cappedmesasthatarelocallandmarksintheeasterncounties.Atelevationsof5,500to6,000feet
nearthemountainfront,theplainstransitionfairlyabruptlytofoothillsandmesasthat,inturn,
quicklyrisetomontaneelevations.Thecentralportionofthestateisdominatedbythepeaksand
rangesoftheSouthernRockyMountains.Here,aseriesofmountainrangestrendinggenerally
north‐southboundastringofhighmountainvalleysorparks,andincludemorethanfiftypeaks
reachingelevationsof14,000feetormore.Tothewest,moremountainsandextensiveplateaus,
heavilydissectedbyravinesandcanyons,formthecharacteristicvalleyandplateauwesternslope
landscape.Nearthewesternborderofthestateelevationsdecreaseagain,reachingalowofabout
4,325feetwheretheColoradoRivercrossestheborderwithUtah.
ClimateChangeVulnerabilityAssessmentforColoradoBLM5
General climate
Colorado’spositionatthehighpointofthecontinentmeansthatseveraldifferentweatherpatterns
influencetheclimateofthestate,andhenceitsvegetation.Ingeneral,higherelevationshavecooler
temperaturesandreceivemoreprecipitation,althoughlocaltopographyhasasignificanteffecton
airmovementscontrollingthesefactors.MoisturemayreachthestatefromeitherthePacificOcean
ortheGulfofMexico,dependingoncurrentaircirculation.Stormsoriginatingtothewestofthe
statedropmuchoftheirmoistureasrainorsnowonthemountainsandwestern‐facingslopes;a
rain‐shadoweffectpreventsmostofthisprecipitationfromreachingtheeasternplains.The
westernpartofColoradoreceivesmostofitsyearlyprecipitationduringwintermonths.Moisture
fromtheGulfofMexicocanproduceheavyprecipitationontheeasternslopeofthedivide,
especiallyinspringandsummer,andtheplainsreceivethemajorityoftheirannualprecipitation
duringthegrowingseason.Southernportionsofthestategenerallyreceivemid‐tolate‐summer
precipitationasthemarginoftheNorthAmericanMonsoonmovesnorth.
Geology and soils
Thelandscapeweseetodayistheproductofbothpastandongoinggeologicprocesses.Theeffects
ofcontinentaldrift,geologicuplifts,volcaniceruption,anderosionhaveresultedinahighly
complexarrangementofrockandsoiltypesthatprovideasubstrateforColorado’snative
vegetation.Colorado’seasternplainsaredominatedbysoilsderivedfromTertiary(2‐65mya)and
Cretaceous(65‐140mya)sedimentaryformations,shapedbytheactionofflowingwaterandwind.
Inthecentralportionofthestate,theColoradoRockyMountainsareformedofigneousand
metamorphicrockthatisthrustupthroughthesedimentarylayerstotheeastandwest.Heresoils
aregenerallylesswelldeveloped,exceptinlow‐lyingareas,whereerosionhasdeposited
substantialsoilmaterial.ThewesternplateausandvalleysarealsoprimarilyformedinTertiary
andCretaceoussubstrates,andmanysoilshavehighconcentrationsofsaltsandmineralsthat
inhibitplantgrowth.Incombinationwithclimatefactors,soilsareagoodindicatorofwhichtypeof
vegetationwilldominatethelandscapeinaparticulararea.
Land ownership
Ownershippatternsreflectthelandusehistoryofthestate,and,togetherwithmanagement
practicesareanimportantfactorindeterminingtheconservationstatusofColorado’slandscape.
Arablelands,especiallyontheeasternplainsandalongriverdrainages,areprimarilyinprivate
ownership.Colorado’smininghistoryhasleftalegacyofprivateinholdingswithinextensivetracts
ofpublicland.Lowerelevationlandsonthewestslopeusedprimarilyforgrazing,mining,oiland
gasextraction,andrecreationaregenerallyadministeredbytheBureauofLandManagement.
Higherelevation(mostlyforested)partsofthestatearelargelyundertheadministrationoftheU.S.
ForestService,whileNationalGrasslandsadministeredbytheU.S.ForestServiceineastern
ColoradowereformedfromfarmlandreclaimedfromtheravagesoftheDustBowldays.The
distributionofstate‐ownedlandstillreflectstheschoollandgrantincludedinthe1875Enabling
ActfortheTerritoryofColorado,whichprovidedthattwosectionsofeverytownship(usually
sections16and36)begrantedforthesupportofpublicschools.
6ColoradoNaturalHeritageProgram©2015
About57%ofthestate’ssurfaceacresareprivatelyowned,withtheremainderinfederal,state,
localgovernment,ortribalownership.Federalpubliclandsaccountforalittleover36%of
Coloradoacreage.TheBLMadministers8.4millionacres(13%)ofColorado’ssurfaceacres,aswell
asover29millionacresofsub‐surfacemineralestate.OtherfederallandsinColoradoare
administeredU.S.ForestService(22%ofstateacreage),NationalParkService(1%),andother
federalagenciesincludingtheU.S.FishandWildlifeService,BureauofReclamation,and
DepartmentofDefense(<1%).TheStateofColoradoownsnearly5%oftheacreage,andalsoholds
aboutamillionacresofsub‐surfacemineralestateonlandsinotherownership.Triballands
accountforabout1%ofColorado’sacreage,andtheremainderisownedbygovernmentsatthe
countyandcitylevel.
Human influence on the landscape
Inadditiontonaturaldisturbanceprocessessuchasfire,wind,andflooding,theeffectsofhuman
activitieshavealsochangedpatternsofdisturbanceinColorado.ThesettlementhistoryofColorado
hasresultedinapatternoflandownershipwherepubliclandsareasignificantpartofthe
landscape.
Development
Althoughindustrial,urban,suburban,andexurbandevelopmentinColoradoaregenerallynot
occurringonpubliclands,theseactivitiesareasourceofpotentialdisturbancetoadjacentareas.
Colorado’stotalpopulationofover5millionislargelyconcentratedintheFrontRangecorridor
fromPueblonorthtoFortCollinswhere11countiesaccountfor83%ofthestate’spopulation.
LargercitiesoutsidethisareaincludeGrandJunction,Montrose,andDurango.Anetworkof
highways,roads,andothertransportationcorridors,togetherwithutilityright‐of‐waysofvarious
typesconnectspopulatedplaceslargeandsmallthroughoutthestate.Inspiteofthestate’s
increasingpopulation,andpatchworkofprivateandpubliclands,morethan75%ofColorado’s
landscaperemainscoveredbynaturalvegetation,especiallyinhigherelevationareas.
ResourceExtractionandEnergyDevelopment
Miningforcoal,gold,gypsum,limestone,silver,molybdenum,sodaash,sodiumbicarbonate,sand,
gravel,andcrushedstone,aswellastheextractionofpetroleumandnaturalgas,havehada
significantroleinshapingColorado’slandscape.Energydevelopmentisasignificantandexpanding
activityinColorado,especiallyinthenaturalgasandoil‐richareasofthenorthernFrontRangeand
westernslope.Beginninginthe1860s,coalandpetroleumwerethefirstenergyresourcestobe
developedinColorado.Togetherwithnaturalgasandoilshale,thesefossilfuelshavehistorically
constitutedthemajorityofenergydevelopmentinthestate.TheBLMadministersmineralleasing
forallfederallandsinColoradowheresuchrightshavenotbeenwithdrawn,aswellasforsplit‐
estatefederalmineralrightsundernon‐Federallands.Aspartofitstrustresponsibility,theBLM
alsooverseesmineraloperationsontriballands.
RenewableenergyfacilitieshavenotbeendevelopedonBLMlands.Coloradocurrentlyhasover
1,500windturbinesinoperation,primarilyontheeasternplains.Concentratedsolarenergy
facilitiesarealsobeingdevelopedinseveralareasofthestate.However,withtheprojectedfuture
ClimateChangeVulnerabilityAssessmentforColoradoBLM7
growthoftheseindustries,Coloradocanexpecttoseeanincreaseintransmissionlineconstruction
thatmayinvolveBLMadministeredlands.
Agriculture
TheoriginalgrasslandsofColorado’seasternplainswerehometolargenumbersofgrazinganimals
includingdeer,pronghorn,elkandbison.WithEuropeansettlement,thesenativegrazerswere
largelyreplacedbydomesticlivestock.Large‐scalegrazingbeganinthe1860s,andquickly
expandedasrailroadsprovidedaccesstoeasternmarkets.BoththeBureauofLandManagement
andtheU.S.ForestServiceissuegrazingpermitsforpubliclandsinColorado,andstate‐owned
landsmayalsobeleasedforgrazing.Cattleandassociatedproductsformthelargestportionof
Colorado’sagriculturalcashreceipts,followedbyfieldcrops(USDANASS2015).Around1900,crop
farmingbegantoexpandinthestate,withwheatandcornastheprimaryproducts.Although
periodicdroughtshaverepeatedlydealthardblowstofarmingandranchinginColorado,theseland
usesstillmakeanimportantcontributiontothestate’seconomy,andhavehadanundeniableeffect
onthearrangementandconditionofColorado’snaturalvegetation.
BLM‐administeredColoradorangelandissubjecttograzingusebypermittedlivestockoperators.
About2,500grazingallotmentsaremanagedbypermitsorleasesthatspecifythekindandnumber
oflivestock,seasonofuse,andamountofusepermittedeachgrazingyear.Permitsorleasesare
subjecttocompliancereviewandpublicscopingpriortorenewal.
RecreationandConservation
Inrecentdecades,recreationhasbecomeanincreasinglyimportantpartoflanduseinColorado.
FromNationalParkstolocalopenspacelands,increasingnumbersofresidentsandvisitorsare
drawntoavarietyofoutdooractivitiessuchashiking,camping,wintersports,hunting,fishing,and
off‐roadvehicleuse.Paradoxically,recreationonColorado’spubliclandscancontributetobothits
conservationanditsdegradation.
AlthoughtheBLMmanagespubliclandsforrecreation,theagencyisalsoresponsiblefor
preservationoftheenvironment,wildlifeandarchaeologicalandpaleontologicalresources;
sustainablenaturalresourceextraction;thevisualappealofpubliclands;andconsidering
socioeconomicimpactsofmanagementdecisions.TheBLM’sapproximatelyonemillionacresof
NationalConservationLandsinColoradoincludetwonationalmonuments,threenational
conservationareas,fivewildernessareas,53wildernessstudyareas,aswellasNationalHistoric
andScenicTrails.TheBLMalsoamanagesanumberofAreasofCriticalEnvironmentalConcernfor
scientific,scenic,ecological,biological,geological,historicalandprehistoricvaluesforpublic
benefit.
8ColoradoNaturalHeritageProgram©2015
CLIMATE CHANGE VULNERABILITY ASSESSMENT
Uncertainty in climate change vulnerability assessment
Theincreasingnumberofclimatechangevulnerabilityassessmentstendstoindicatethatmany
entitiesregardtherealityofclimatechangewithahighlevelofcertainty.However,therearea
numberofsourcesthatintroduceuncertaintyofvaryingdegreeintotheseassessments.Frequently
acknowledgedsourcesofuncertaintyorvariationinprojectedoutcomesarethemodeled
componentsofclimatechangeanalysis:theglobalcirculationmodels,hydrologicmodels,species
responsemodels,andsoon.Withallprojectionsoffutureclimateconditionswecannotknowwith
absolutecertaintywhich,ifany,willturnouttobetrue.Downscalingthesemodelsdoesnotremove
inherentuncertainty.
Uncertaintyinthecontextofclimatechangeisnotequivalenttocompletelackofknowledge.
Currentclimatemodelsrepresentthebestavailablescience,yetdonotallagree.Ingeneral,climate
modelsareunderstoodtohavehigherlevelsofcertaintyaboutglobaltemperatureresponsesto
forcingfactorsthantheydoforprecipitationresponse.Boththedirectionofresponse(increaseor
decrease)andthemagnitude(degrees,inches,etc.)ofresponseofclimatefactorsarevariable
amongclimatemodels.Currently,consensusaboutthedirectionoftemperaturechange
(increasing)isgreaterthanforprecipitation.Themagnitudeofexpectedchangeforbothfactorsis
uncertain.
Comparing the vulnerability of ecosystems and species
Althoughwehaveestimatedthevulnerabilitytoclimatechangeofbothecosystemsandthespecies
thatinhabittheminthefollowingchapters,therearedifferencesofbothmethodandscalebetween
theseassessments.
Forecosystems,exposureandsensitivitywerecombinedintoasinglemetricthatwaspairedwitha
resilience‐adaptivecapacitymetricinascoringmatrixtoproduceanoverallvulnerabilityrank.
SpecieswereassessedusingtheNatureServeClimateChangeVulnerabilityIndexmethod(Younget
al.2015),whichtreatsexposureasamodifierofsensitivityandadaptivecapacity(i.e.,low
exposurediscountssensitivity/adaptivecapacityfactors,andhighexposureamplifiesthose
factors).
Ecosystemswereassessedusingtherepresentativeconcentrationpathway(RCP8.5)emissions
scenariomethodoftheIPCCFifthAssessmentReport,whilebothanimalandplantspecieswere
assessedunderA2scenariooftheSpecialReportonEmissionsScenarios(SRES)standards
employedintwopreviousIPCCreports.ThisdifferenceisduetotheuseoftheNatureServeCCVI,
whichisbasedontheearliermethodology,forspeciesonly.Forthemid‐centurytime‐frameofour
assessment,theSRESA2scenarioprojectsCO2concentrationlevelsandtemperatureincreasesthat
areslightlyloweronaveragethanthoseprojectedbytheRCP8.5scenario.However,thetwo
scenariosareapproximatelyequivalentinthattheyarebasedonsimilarunderlyingassumptions
ClimateChangeVulnerabilityAssessmentforColoradoBLM9
aboutfuturedemographicandeconomictrends,andaregenerallyregardedas“worst‐case”
scenarios.Neitherscenarioisconsidered‘better’thantheotherbytheclimatesciencecommunity.
Inaddition,thecorrelationofplantandanimalspecieswithasingleecosystemisrare,especially
formobileanimalspecies.Becauseofthisvariability,andalsobecauseofdifferencesinscale
betweenindividualorganismlife‐cyclefactorsandlandscapelevelprocesses,itispossibleforthe
vulnerabilityofaparticularspeciestobedifferentfromthatofitsprimaryecosystem.
Previous vulnerability assessments in the Colorado region
Priortotheeffortreportedherein,anumberofstudieshaveevaluatedvulnerabilitytochanging
climaticconditionsinandaroundColorado(Table1.1).AdditionalreportsnotincludedinTable1.1
havealsoaddressedthevulnerabilitytoclimatechangeofavarietyofsocio‐economicelements.
Thelistedstudiesemployedanassortmentofqualitativeandquantitativeapproaches;anumberdo
notexplicitlyaddressindividualhabitatsorspecies.Furthermore,spatialscalesoflisted
assessmentsdifferbyonetothreeordersofmagnitude.Anelementthatisconsideredhighly
vulnerabletoextinctioninasmallareamayhavesignificantlyreducedvulnerabilityinother
portionsofitsrange.Consequently,acomparisonofvulnerabilityrankingresultsacrossthese
effortsisproblematic.Nevertheless,afewgeneraltrendsareevidentacrossvulnerability
assessments.Speciesandhabitatsofhigherelevationsareusuallyconsideredmorevulnerablethan
thoseofmid‐elevationareas.Speciesandhabitatsthatareextremelycloselyassociatedwithwater
resourcesaregenerallyexpectedtohavehighervulnerabilitythanthoseinmorexericconditions.
Agreementaboutvulnerabilityforsomedrymid‐to‐lowerelevationhabitatsispoor.Forinstance,
pinyon‐juniperwoodlandsandsagebrushshrublandshavereceivedrankingsrangingfromHighly
VulnerabletoLikelytoIncrease,dependingonthescale,location,andmethodofassessment.This
disagreementillustratestheimportanceofattentiontoscaleandtime‐frameinthedevelopmentof
managementgoalsandobjectivesforclimateadaptationplanning,andhighlightsareaswhere
additionalresearchtoaddresswell‐formulatedquestionsmaybeneeded.
10ColoradoNaturalHeritageProgram©2015
Table 1.1.SummaryofclimatechangevulnerabilityassessmentsintheColoradoregionthathaveaddressedhabitatsorspecies.
Full Citation Area Habitats Species Target Time
Frame &
Emissions
Scenario
Methodology Vulnerability
Ranking (see
codekey
below)
Brownetal.2008.ClimateChangeinRockyMountain
NationalPark.
http://www.nps.gov/romo/parkmgmt/upload/climate_cha
nge_rocky_mountain2.pdf
RockyMtn.
NationalPark
Wetlands,lakes
&streams,
montane,
subalpine,
alpine
‐‐‐‐ NonegivenQualitative
(workshop
narrative
synthesis)
Norankings
Ray,A.J.,J.J.Barsugli,andK.B.Averyt.2008.Climatechange
inColorado:Asynthesistosupportwaterresources
managementandadaptation.ReportforColoradoWater
ConservationBoard.WesternWaterAssessment
http://wwa.colorado.edu/publications/reports/WWA_Clim
ateChangeColoradoReport_2008.pdf
StatewideWater
resources,no
individual
habitats
explicitly
addressed
‐‐‐‐ Mid‐century.
CMIP3B1,
A1B,A2
ensembles
Qualitative
(narrative
synthesis)
Norankings
Reiman,B.E.andD.J.Isaak.2010.Climatechange,aquatic
ecosystems,andfishesintheRockyMountainWest:
Implicationsandalternativesformanagement.General
TechnicalReportRMRS‐GTR‐250.USDAForestService,
RockyMountainResearchStation.FortCollins,CO.
http://www.fs.fed.us/rm/pubs/rmrs_gtr250.pdf
Western
Colorado,as
partofRocky
Mtn.west
Stream
environments,
including
riparian
NativefishesNonegivenQualitative
(narrative
synthesis)
Norankings‐
habitatlossor
gain.
ColoradoNaturalHeritageProgramforRarePlant
ConservationInitiative.2011.ColoradoWildlifeActionPlan:
proposedrareplantaddendum.LeeGrunau,JillHandwerk,
andSusanSpackman‐Panjabi,eds.ColoradoNatural
HeritageProgram,ColoradoStateUniversity,FortCollins,
CO.
http://www.cnhp.colostate.edu/download/documents/201
1/rareplant_SWAP_final_june_30_2011_formattedv2.pdf
Statewide ‐‐‐‐ 121G1and
G2plants
Mid‐century.
A2
Quantitative
(NatureServe
CCVI)
EV/HV/MV/PS/IL
/IE
ClimateChangeVulnerabilityAssessmentforColoradoBLM 11
Full Citation Area Habitats Species Target Time
Frame &
Emissions
Scenario
Methodology Vulnerability
Ranking (see
codekey
below)
Neely,B.,R.Rondeau,J.Sanderson,C.Pague,B.Kuhn,J.
Siemers,L.Grunau,J.Robertson,P.McCarthy,J.Barsugli,T.
Schulz,andC.Knapp,Eds.2011.GunnisonBasin:
VulnerabilityAssessmentfortheGunnisonClimateWorking
GroupbyTheNatureConservancy,ColoradoNatural
HeritageProgram,WesternWaterAssessment,University
ofColorado,Boulder,andUniversityofAlaska,Fairbanks.
ProjectoftheSouthwestClimateChangeInitiative.
http://wwa.colorado.edu/publications/reports/TNC‐CNHP‐
WWA‐
UAF_GunnisonClimChangeVulnAssess_Report_2012.pdf
GunnisonBasin17terrestrial
ecosystemsand
7freshwater
73speciesof
conservation
concern
Mid‐century.
CMIP3A2‐
Barsugliand
Mearns2010
projected
climate
scenarios.
Qualitative
(Manomet‐
MADFW,expert
opinion),
quantitative
(NatureServe
CCVI)
Uplands:
EV/HV/MV/PS/SI.
MI/GI/U
Riparian:H/M/L
Species:
EV/HV/MV/PS/IL
/IE
Nydick,K.,Crawford,J.,Bidwell,M.,Livensperger,C.,
Rangwala,I.,andCozetto,K.2012.ClimateChange
AssessmentfortheSanJuanMountainRegions,
SouthwesternColorado,USA:AReviewofScientific
Research.PreparedbyMountainStudiesInstitutein
cooperationwithUSDASanJuanNationalForestService
andUSDOIBureauofLandManagementTresRiosField
Office.Durango,CO.
http://www.mountainstudies.org/s/ClimateResearchRevie
w_SJMs_FINAL.pdf
Southwest
Colorado
Sagebrush,oak,
PJ,Ponderosa,
Mixedconifer,
aspen,
subalpine,
alpine,riparian,
fens&wet
meadows
7taxonomic
groups
Mid‐century.
NARCCAP
(CMIP3A2)
Qualitative
(narrative
relatesto
regionalclimate
models,and
synthesizes
workbyothers)
Decrease–noor
littlechange‐
increase
Woodbury,M.,M.Baldo,D.Yates,andL.Kaatz.2012Joint
FrontRangeClimateChangeVulnerabilityStudy.Water
ResearchFoundationandTailoredCollaborationpartners.
Denver,CO.http://cwcb.state.co.us/environment/climate‐
change/Pages/JointFrontRangeClimateChangeVulnerability
Study.aspx
NorthCentral
Colorado
(Headwatersof
SouthPlatte,
Arkansas,
Coloradorivers)
Streams ‐‐‐‐ 2040and
2070.Selected
CMIP3A2
ensembles
Quantitative
(models)
Norankings
USDAForestService,Region2.UNPUBLISHED.CCVAsfor
selectedhabitats.
 
Decker,K.andR.Rondeau.2014.SanJuan/TresRios
ClimateChangeEcosystemVulnerabilityAssessment.
ColoradoNaturalHeritageProgram,ColoradoState
University,FortCollins,Colorado.
http://www.cnhp.colostate.edu/download/documents/201
4/SJRA_ecological_systems_vulnerability_analysis_FINAL.p
df
Southwest
Colorado(San
Juan/TresRios
management
area)
14uplandand3
wetland/
riparian
ecosystems
‐‐‐‐ Mid‐century.
SuiteofCMIP5
RCP4.5&8.5
models‐3
scenarios–
Rangwala
2012
Qualitative
(modified
Manomet‐
MADFW,expert
opinionand
narrative
synthesis)
EV/HV/MV/PS/SI
/MI/GI/U
12ColoradoNaturalHeritageProgram©2015
Full Citation Area Habitats Species Target Time
Frame &
Emissions
Scenario
Methodology Vulnerability
Ranking (see
codekey
below)
Handwerk,J.,B.Kuhn,R.Rondeau,andL.Grunau.2014.
ClimateChangeVulnerabilityAssessmentforRarePlantsof
theSanJuanRegionofColorado.ColoradoNaturalHeritage
Program,ColoradoStateUniversity,FortCollins,Colorado.
http://www.cnhp.colostate.edu/download/documents/201
4/SanJuan_CCVI_Final_Report.pdf
Southwest
Colorado(San
Juan/TresRios
management
area)
‐‐‐‐ 60rareplant
spp.
Mid‐century.
CMIP3A2
Quantitative
(NatureServe
CCVI)
EV/HV/MV/PS/IL
/IE
Lukas,J.,J.Barsugli,N.Doesken,I.Rangwala,K.Wolter.
2014.ClimatechangeinColorado:Asynthesistosupport
waterresourcesmanagementandadaptation,2ndedition.
AreportfortheColoradoWaterConservationBoard.
WesternWaterAssessment,CooperativeInstitutefor
ResearchinEnvironmentalSciences(CIRES),Universityof
Colorado,Boulder.
http://cwcbweblink.state.co.us/WebLink/0/doc/191995/Ele
ctronic.aspx?searchid=e3c463e8‐569c‐4359‐8ddd‐
ed50e755d3b7
Statewide,and
specific
subregions
Water
resources,no
individual
habitats
explicitly
addressed
‐‐‐‐ Mid‐century.
CMIP3and
CMIP5,pooled
RCPs(4.5&
8.5discussed)
Qualitative
(narrative
synthesis)
Norankings
Decker,K.andM.Fink.2014.ColoradoWildlifeActionPlan
Enhancement:ClimatechangeVulnerabilityAssessment.
ColoradoNaturalHeritageProgram,ColoradoState
University,FortCollins,Colorado.
http://www.cnhp.colostate.edu/download/documents/201
4/CO_SWAP_Enhancement_CCVA.pdf
Statewide13terrestrial
habitats
‐‐‐‐ Mid‐century.
BCCACMIP5‐
RCP6.0
Quantitative
(models–
projectedrange
shift)
VH/H/M/L
Pocewicz,A.,H.E.Copeland,M.B.Grenier,D.A.Keinath,and
L.M.Washkoviak.2014.Assessingthefuturevulnerabilityof
Wyoming’sterrestrialwildlifespeciesandhabitats.Report
preparedbyTheNatureConservancy,WyomingGameand
FishDepartmentandWyomingNaturalDiversityDatabase.
http://www.nature.org/media/wyoming/wyoming‐wildlife‐
vulnerability‐assessment‐June‐2014.pdf
Adjacentto
Colorado
11habitat
types,largely
analogousto
Coloradotypes
131Species
ofgreatest
conservation
need
Mid‐century.
A2
Quantitative
(models–
annualmean
temperature&
moisturedeficit,
NatureServe
CCVI)
VH/H/M/L
Gordon,E.andD.Ojima,eds.2015.ColoradoClimate
ChangeVulnerabilityStudy.AreportbytheUniversityof
ColoradoBoulderandColoradoStateUniversitytothe
ColoradoEnergyOffice.
http://wwa.colorado.edu/climate/co2015vulnerability/co_v
ulnerability_report_2015_final.pdf
StatewideBroad
categories:
Alpine,Forests,
andGrasslands
‐‐‐‐ Mid‐century?Qualitative
(narrative
synthesis)
Norankings‐key
vulnerabilitiesfor
broadcategories
ClimateChangeVulnerabilityAssessmentforColoradoBLM 13
Full Citation Area Habitats Species Target Time
Frame &
Emissions
Scenario
Methodology Vulnerability
Ranking (see
codekey
below)
Handwerk,J.,L.Grunau,andSSpackman‐Panjabi,eds.
ColoradoWildlifeActionPlan:2015RarePlantAddendum.
ColoradoNaturalHeritageProgram,ColoradoState
University,FortCollins,Colorado.
http://www.cnhp.colostate.edu/download/reports.aspx
Statewide ‐‐‐‐ 117G1orG2
plants
Mid‐century.
CMIP3A2
Quantitative
(NatureServe
CCVI)
EV/HV/MV/PS/IL
/IE
THISDOCUMENT(CNHP2015)
Statewide16terrestrial
habitatsand6
freshwater
groups
97speciesof
conservation
concern
Mid‐century.
NEX‐DCP30–
CMIP5RCP8.5
&CMIP3A2
Quantitative
(models–outof
range
conditions,
NatureServe
CCVI)
Ecosystems:
VH/H/M/L
Species:
EV/HV/MV/PS/IL
/IE
Rank Definition
NatureServeCCVIhttp://www.natureserve.org/conservation‐tools/climate‐change‐vulnerability‐index(inCNHPRPCI2011,Neelyetal.2011,Handwerketal.2014&2015,
CNHP2015)
EV‐ExtremelyVulnerableAbundanceand/orrangeextentwithingeographicalareaassessedextremelylikelytosubstantiallydecreaseordisappearby
2050.
HV‐HighlyVulnerableAbundanceand/orrangeextentwithingeographicalareaassessedlikelytodecreasesignificantlyby2050.
MV‐ModeratelyVulnerableAbundanceand/orrangeextentwithingeographicalareaassessedlikelytodecreaseby2050.
PS‐PresumedStableAvailableevidencedoesnotsuggestthatabundanceand/orrangeextentwithinthegeographicalareaassessedwillchange
(increase/decrease)substantiallyby2050.Actualrangeboundariesmaychange.
IL‐NotVulnerable/IncreaseLikelyAvailableevidencesuggeststhatabundanceand/orrangeextentwithingeographicalareaassessedislikelytoincreaseby
2050.
IE‐InsufficientEvidenceAvailableinformationaboutaspecies'vulnerabilityisinadequatetocalculateanIndexscore.
Neelyetal.(2001),Decker&Rondeau(2014) 
EV‐ExtremelyVulnerableEcosystematriskofbeingeliminatedfromtheareaasaresultofclimatechange.
HV‐HighlyVulnerableMajorityofecosystematriskofbeingeliminated(i.e.,>50%loss)asaresultofclimatechange,butunlikelytobeeradicated
entirely.Forriparian,overalllossofsystemisexpectedtobe>50%orecologicalprocessisexpectedtobeseverelyimpacted,
e.g.,floodfrequencyoccurs50%lessthancurrentfloodingregime.
MV‐ModeratelyVulnerableExtentofecosystematriskofbeingmoderatelyreduced(<50%loss)asaresultofclimatechange.Forriparian,overalllossof
systemisexpectedtobe>50%orecologicalprocessisexpectedtobeseverelyimpacted,e.g.,floodfrequencyoccurs50%
lessthancurrentfloodingregime.
LV‐LowVulnerabilityForriparianonly,0to10%lossofareaandconditionofsystemremainsstable.
PS‐PresumedStableExtentofecosystemapproximatelythesame,buttherearesignificantpatternorconditionchangeswithinthearea.
SI‐SlightIncreaseEcosystemmaybecomeestablishedwithinthebasinfromareasoutside.
MI‐ModerateIncreaseExtentofecosystemmayexpandmoderately(<50%gain)asaresultofclimatechange.
14ColoradoNaturalHeritageProgram©2015
Rank Definition
GI‐GreatlyIncreaseEcosystemmayexpandgreatly(>50%gain)asaresultofclimatechange.
U‐UnknownVulnerabilityofecosystemunderclimatechangeisuncertain
Decker&Fink(2014),CNHP(2015) 
VH‐VeryHighVulnerabilityHabitats/ecosystemshavehighvulnerabilitytoclimatechangewhenexposureandsensitivityarehigh,andadaptivecapacity
andresiliencearelow.Transformationofthehabitat/ecosystemismostlikelytooccurinupcomingdecades.
HV‐HighlyVulnerableHigh vulnerabilitytoclimatechangeresultsfromcombiningeitherhighormoderateexposure‐sensitivitywithlowormedium
adaptivecapacity‐resilience.Undereithercombination,climatechangeislikelytohavenoticeableimpact.
MV‐ModeratelyVulnerableModeratevulnerabilitytoclimatechangeresultsfromavarietyofcombinationsforexposure‐sensitivityandadaptive
capacity‐resilience.Thenumberofpossiblecombinationsindicatesadegreeofuncertaintyinthevulnerabilityranking.Under
circumstanceswherethetwofactorsareessentiallybalanced,vulnerabilityisthoughttobereduced,butstillofconcern.
LV‐LowVulnerabilityLowvulnerabilitytoclimatechangeoccurswhenahabitatcombineslowexposureandsensitivitywithhighormoderate
adaptivecapacityandresilience.Forthesehabitats/ecosystemsclimatechangestressanditseffectsareexpectedtobeleast
severeorabsent.
ClimateChangeVulnerabilityAssessmentforColoradoBLM15
Climate change in Colorado
AnnualaveragetemperaturesacrossColoradohaveincreasedby2.0°Foverthepast30years
(Figure1.2a).Warmertemperaturesareevidentforallseasons,anddailyhighandlow
temperatureshavealsoincreased(Lucasetal.2014).Incontrast,overtheperiodofrecord,there
arenocomparabletrendsinaverageannualprecipitationinColorado(Figure1.2b),although
snowpacklevelshavebeengenerallybelowaveragesince2000.Thedecreaseinsnowpack,along
withwarmingspringtemperaturesandtheeffectsofincreaseddust‐on‐snowhavecombinedto
shiftthetimingofsnowmeltandpeakrunofffrom1‐4weeksearlier(Lucasetal.2014).Flowering
datesforsomeplantspeciesareoveramonthearlierthantheywereacenturyago(Munsonand
Sher2015).DroughtconditionsasmeasuredbythePalmerDroughtSeverityIndexalsoreflect
warmingtemperaturesandtherecentperiodofbelowaverageprecipitiation(Figure1.2c).
ReconstructionsofdroughtsinwesternNorthAmericashowanumberofdroughtspriortothe
instrumentalrecordthatweremoresevereandlongerlastingthantheworstdroughtsofthepast
century(Woodhouse2004,Stahleetal.2007,Routsonetal.2011),whichillustratestherelatively
narrowviewofvariabilityprovidedbythehistoricalrecord.Bothhistoricandpre‐instrumental‐
recorddroughtshavehadnotableeffectsonvegetationpatterns,andhaveseverelyimpacted
patternsofhumanhabitationandsocialinteraction(Woodhouse2004,Bensonetal.2007).The
possibilityoffuturedroughtsthatgreatlyexceedthemostseveredroughtsofthepastmilleniacan
notbeexcluded(Cooketal.2015).
Projectionsbasedon17models(NASAEarthExchangeDownscaled30Arc‐SecondCMIP5Climate
ProjectionsdatasetfortheconterminousU.S.,Thrasheretal.2013),rununderRCP8.5andRCP4.5
forthe30‐yearperiodcenteredon2050indicatethatallareasofColoradowillexperiencesome
degreeofwarming,andpotentiallychangesinprecipitationaswell.Temperaturechange
projectionsareregardedasmorecertain(Barsuglipers.comm.),andthereisgeneralagreement
thatconditionshavealreadywarmedtosomedegree(Lucasetal.2014);uncertaintyfor
temperaturechangeisgreaterregardingthemagnitudeoftheprojectedchange.Incombination
withexpectedchangesintemperature,however,evenawetterfuturemaynotbesufficientto
maintainrunoffandsoilmoistureconditionssimilartothoseoftherecentpast.Climateprojections
presentedherearesummariesoflong‐termtrendsanddonottrackinter‐annualvariation,which
willremainasourceofvariability,asithasbeeninthepast.Ourecosystemanalysisfocusedona
singlerepresentativeconcentrationpathway(RCP8.5)andalimitedsubsetofavailableglobal
circulationmodels;atthispointintimewehavenowayofknowingifthisisthescenariothatwill
befoundvalidbymid‐century.However,inallscenarios,changesthatinthepastoccurredover
periodsofseveralthousandyearsarenowprojectedtotakeplaceinonlyahundredyears.
ProjectedchangessummarizedinFigure1.3aindicateaverageseasonaltemperatureincreasesof
anywherefromabout3.5‐5.8F,withmeanincreasesofabout4.1‐5.4F.Furthermore,minimum
andmaximumtemperatureincreasesarealsoprojectedforallseasons.Somewhatgreater
increasesareprojectedunderRCP8.5incomparisonwithRCP4.5atmid‐century.Winterminimum
temperaturesareprojectedtohavegreaterincreasesthanwintermaximumtemperatures,butin
allotherseasonsthegreatestincreasesareprojectedinmaximumtemperatures,andtheleastin
16ColoradoNaturalHeritageProgram©2015
(a)
(b)
(c)
Figure 1.2.Historical(1990‐2014)Coloradostatewidetrendsfor(a)annualmeantemperature,(b)annual
precipitation,and(c)PalmerDroughtSeverityIndex.Temperatureandprecipitationareshownasdeparturefrom
themeanofbaseperiod(1901‐2000).DataarefromNOAANationalCentersforEnvironmentalInformation:
http://www.ncdc.noaa.gov/cag/data‐info.
ClimateChangeVulnerabilityAssessmentforColoradoBLM17
minimumtemperatures(Figure1.3a).Rangesofprojectedincreaseforallseasonsarebroadly
overlapping.
Meanprojectedprecipitationchangesaregenerallylesscertainthanthosefortemperature,and
maynotbeoutsidetherangeofhistoricvariability,atleastbymid‐century.Seasonalprojected
percentincreasesinprecipitationareonaveragegreatestforwinterandspring(Figure1.3b),while
summerandfallareprojectedtohavedecreasedoressentiallyunchangedprecipitation.However,
rangesforgrowingseasonsincludebothincreasedanddecreasedprecipitation.
(a)(b)
Figure 1.3.Seasonalprojectedtemperature(a)andprecipitation(b)changesbymid‐21stcentury(2050;centered
around2035‐2064period)forColorado.
Fortemperature(a),thebottomofeachbarrepresentsthe10
th
percentile,andthetopofthebaristhe90
th
.Meanprojected
changeisrepresentedbyopendiamonds.RCP8.5statewideprojectedchangeinaverageseasonaltemperaturesarethetop
(red)bars,andRCP4.5arebottom(purple)bars.Forprecipitation(b),thebottomofeachbarrepresentsthe10
th
percentile,the
middlelineisthe50
th
,andthetopofthebaristhe90
th
.RCP8.5statewideprojectedpercentchangeinseasonalaverage
precipitationaretheleft‐handbars,andRCP4.5aretheright‐handbars.Seasonsare:winter=DJF,spring=MAM,summer=JJA,
andfall=SON.Atemperatureintervalof1°Fisequaltoanintervalof5⁄9degreesCelsius.Climatescenariosusedwerefromthe
NEX‐DCP30dataset,preparedbytheClimateAnalyticsGroupandNASAAmesResearchCenterusingtheNASAEarthExchange,
anddistributedbytheNASACenterforClimateSimulation(NCCS).
Literature Cited
Benson,L.,K.Petersen,andJ.Stein.2007.Anasazi(Pre‐ColumbianNative‐American)migrationsduringthemiddle‐12
th
andlate‐13
th
centuries–weretheydroughtinduced?ClimaticChange83:187‐213.
Cook,B.I.,T.R.Ault,andJ.E.Smerdon.2015.Unprecedented21
st
centurydroughtriskintheAmericanSouthwestand
CentralPlains.ScienceAdvances12Feb2015;1:e1400082.
Lukas,J.,J.Barsugli,N.Doesken,I.Rangwala,K.Wolter.2014.ClimatechangeinColorado:Asynthesistosupportwater
resourcesmanagementandadaptation,2ndedition.AreportfortheColoradoWaterConservationBoard.WesternWater
Assessment,CooperativeInstituteforResearchinEnvironmentalSciences(CIRES),UniversityofColorado,Boulder.
18ColoradoNaturalHeritageProgram©2015
Munson,S.M.andA.A.Sher.2015.Long‐termshiftsinthephenologyofrareandendemicRockyMountainplants.
AmericanJournalofBotany102:1‐9.
Routson,C.C.,C.A.Woodhouse,andJ.T.Overpeck.2011.SecondcenturymegadroughtintheRioGrandeheadwaters,
Colorado:Howunusualwasmedievaldrought?GeophysicalResearchLetters38,L22703,doi:10.1029/2011GL050015.
Stahle,D.W.,F.K.Fye,E.R.Cook,R.D.andGriffin.2007.Tree‐ringreconstructedmegadroughtsoverNorthAmericasince
A.D.1300.ClimaticChange83:133‐149.
Thrasher,B.,J.Xiong,W.Wang,F.Melton,A.MichaelisandR.Nemani.2013.DownscaledClimateProjectionsSuitablefor
ResourceManagement.Eos,TransactionsAmericanGeophysicalUnion94:321‐323.
U.S.DepartmentofAgriculture,NationalAgriculturalStatisticsService[USDANASS].2015.2014StateAgricultural
OverviewforColorado.http://www.nass.usda.gov/Quick_Stats/Ag_Overview/stateOverview.php?state=COLORADO
Woodhouse,C.A.2004.ApaleoperspectiveonhydroclimaticvariabilityinthewesternUnitedStates.AquaticSciences
66:346‐356.
Young,B.E.,E.Byers,G.Hammerson,A.Frances,L.Oliver,andA.Treher.2015.GuidelinesforusingtheNatureServe
ClimateChangeVulnerabilityIndex.Release3.0.NatureServe,Arlington,VA.http://www.natureserve.org/biodiversity‐
science/publications/guidelines‐using‐natureserve‐climate‐change‐vulnerability‐index‐0
ClimateChangeVulnerabilityAssessmentforColoradoBLM19
2 ECOSYSTEMS
Authors:
KarinDecker
MichelleFink
Recommendedchaptercitation:
Decker,K.andM.Fink.2015.Ecosystems.Chapter2InColoradoNaturalHeritageProgram2015.ClimateChangeVulnerability
AssessmentforColoradoBureauofLandManagement.K.Decker,L.Grunau,J.Handwerk,andJ.Siemers,editors.Colorado
NaturalHeritageProgram,ColoradoStateUniversity,FortCollins,Colorado.

20ColoradoNaturalHeritageProgram©2015
TableofContents–2Ecosystems
TerrestrialEcosystems–Methods..............................................................................................................23
TerrestrialEcosystems‐Results.................................................................................................................29
LiteratureCited...........................................................................................................................................40
ForestandWoodland.................................................................................................................................42
Aspen....................................................................................................................................................43
Lodgepole.............................................................................................................................................50
Mixedconifer.......................................................................................................................................56
Pinyon‐Juniper......................................................................................................................................62
Ponderosa.............................................................................................................................................70
Spruce‐fir..............................................................................................................................................76
Shrubland....................................................................................................................................................84
Desertshrubland
..................................................................................................................................85
Oak&Mixedmountainshrub..............................................................................................................91
Sagebrush.............................................................................................................................................97
Sandsage.............................................................................................................................................103
GrasslandorHerbaceous..........................................................................................................................108
Alpine..................................................................................................................................................109
Montanegrasslands...........................................................................................................................116
Semi‐desertgrassland........................................................................................................................123
Shortgrassprairie...............................................................................................................................128
RiparianandWetland...............................................................................................................................136
Riparianwoodlandsandshrublands..................................................................................................137
Wetlands............................................................................................................................................144
FreshwaterEcosystems–Methods..........................................................................................................150
FreshwaterEcosystems‐Results..............................................................................................................158
Streams,Rivers,Lakes,andReservoirs..............................................................................................159

ClimateChangeVulnerabilityAssessmentforColoradoBLM21
ListofFigures
Figure 2.1.Statewideenvelopeofprojectedchangeinannualmeantemperatureandprecipitation
undertwoemissionsscenarios(boxes),incomparisonwithlevelsofprecipitationincreaserequiredto
maintainthestatusquo.............................................................................................................................. 25
Figure 2.2.Vulnerabilityrankingmatrix.....................................................................................................28
Figure 2.3.ProjectedannualchangeinColoradofor(a)uplandecosystems,and(b)wetlandandriparian
ecosystems.Ecosystemmeansarecoloredtoindicatethedegreetowhichtheecosystemisprojectedto
experienceconditionsthatareoutofrangeofthoseinitscurrentstatewidedistribution......................29
Figure 2.4.Comparisonofscoresbyecosystemfor(a‐e)individualresiliencefactors,and(f)overall
resilience–adaptivecapacityscore.Backgroundcolorsreflectthelow(red),moderate(orange),and
high(green)resiliencecategories...............................................................................................................30
Figure 2.5.AreaofecosystemsmappedatvariouselevationsinColorado...............................................31
Figure 2.6.Bioclimaticenvelopeasrepresentedbyannualprecipitationandmeantemperaturefor
ecosystemsinColorado.Errorbarsrepresentthe10‐90%rangearoundthemean.................................32
Figure 2.7.MinimumwinterandmaximumsummertemperaturerangesforecosystemsinColorado.
Boxesrepresentthemiddlequartiles,whilewhiskersshowthe10‐90%range........................................33
Figure 2.8.Projectedseasonalaverageprecipitationandmeantemperaturetrajectoriesforcurrent
uplandecosystemrangesinColoradobymid‐centuryunderahighradiativeforcingscenario(RCP8.5).
Circlesrepresentcurrentconditions..........................................................................................................38
Figure 2.9.Projectedseasonalaverageprecipitationandmeantemperaturetrajectoriesforcurrent
wetlandandriparianecosystemrangesinColoradobymid‐centuryunderahighradiativeforcing
scenario(RCP8.5).Circlesrepresentcurrentconditions............................................................................39
Figure 2.10.STORETstationswithJulywatertemperaturereadings......................................................151
Figure 2.11.PredictionStandardError..................................................................................................... 151
Figure 2.12.Interpolatedwatertemperature67‐69°Ffilledcontour,splitintoNorth‐West,North‐
Central,South‐West,andSouth‐Centralsections.ColorsrepresentthemeanJulyairtemperature
coincidingwitheachcontoursection.......................................................................................................152
Figure 2.13.Modeledtransitionline........................................................................................................154
Figure 2.14.Decision‐treeforexposurecriteriaappliedtoriversandstreams.......................................155
Figure 2.15.Categorytransitionsbetweencurrentandprojected(RCP8.5)conditionsforstreamsand
rivers.........................................................................................................................................................165
Figure 2.16.Comparisonofcurrent(top)andprojected(bottom)streamtemperatureclassification..167

22ColoradoNaturalHeritageProgram©2015
ListofTables
Table 2.1.Ecosystemsassessedforvulnerabilitytoclimatechange.........................................................23
Table 2.2.Criteriaforscoringexposureofterrestrialecosystems.............................................................25
Table 2.3.Descriptionoffactorsusedtoassessresilience‐adaptivecapacityinterrestrialecosystems..26
Table 2.4.Vulnerabilityranksummaryforallassessedterrestrialecosystems.........................................36
Table 2.5.Keyvulnerabilities,forestandwoodlandecosystems...............................................................42
Table 2.6.Keyvulnerabilities,shrublandecosystems................................................................................84
Table 2.7.Keyvulnerabilities,grasslandorotherherbaceousecosystems.............................................108
Table 2.8.Keyvulnerabilities,riparianandwetlandecosystems.............................................................136
Table 2.9.Freshwaterecosystemtargets.................................................................................................150
Table 2.10.Meanandstandarddeviation(STD)currentJulyairtemperature(°F)valuesforeachcontour
segmentwithinasection.Valuesinparenthesesare°C..........................................................................153
Table 2.11.Criteriaforscoringexposureoflakesandreservoirsfreshwaterecosystems......................155
Table 2.12.Descriptionoffactorsusedtoassessresilience‐adaptivecapacityinfreshwaterecosystems.
..................................................................................................................................................................156
Table 2.13.FactorsincludedinTNCfreshwatermeasuresofconditiondatabase..................................157
Table 2.14.Keyvulnerabilities,freshwaterecosystems...........................................................................158
Table 2.15.Vulnerabilityranksummaryforallassessedfreshwaterecosystems...................................160
Table 2.16.Representativefishspeciesforfreshwaterecosystems........................................................163
Table 2.17.Reachlengthstatistics(km)forwatertemperaturecategoriesbothstatewideandbyregion.
..................................................................................................................................................................166

ClimateChangeVulnerabilityAssessmentforColoradoBLM23
TERRESTRIAL ECOSYSTEMS ‐ METHODS
Target selection
InconsultationwithBLM,CNHPidentified16terrestrialecosystemtypesorgroupsofinterestfor
BLMmanagementtobeassessed(Table2.1).Terrestrialecosystemdistributionwasmappedusing
SWReGAP(USGS2004)foruplandecosystems,andNationalWetlandInventorymappingfor
riparianandwetlandecosystems(USFWS1975‐2013).Thevulnerabilityofecosystemswas
assessedundertwoprimaryheadings:exposure‐sensitivity,andresilience‐adaptivecapacity.
Scoresforthesetwofactorswerecombinedtoobtainanoverallvulnerabilityrank.
Table 2.1.Ecosystemsassessedforvulnerabilitytoclimatechange.
Terrestrial
Forest and Woodland Grassland or herbaceous
AspenforestAlpine
Lodgepolepineforest Montanegrassland
MixedconiferforestSemi‐desertgrassland
Pinyon‐JuniperwoodlandShortgrassprairie
Ponderosapineforest
Spruce‐FirforestRiparian & Wetland
Riparianwoodland&shrubland‐Eastern
ShrublandRiparianwoodland&shrubland‐Mountain
Desertshrubland Riparianwoodland&shrubland‐Western
Oak&mixedmountainshrublandWetlands‐Eastern
Sagebrushshrubland Wetlands‐Mountain
SandsageshrublandWetlands‐Western
Terrestrial ecosystem responses to climate change
Thepredictionofpotentialplantdistributionunderfutureclimateconditionsisbasedonthe
ecologicalprinciplethatthepresenceofaspeciesonthelandscapeiscontrolledbyavarietyof
bioticandabioticfactors,inthecontextofbiogeographicandevolutionaryhistory.Biotic
interactions(e.g.,competition,predation,parasitism,etc.)togetherwithclimateandotherabiotic
componentsacttoinfluencethespatialarrangementofspeciesatlocal,regional,andcontinental
scales.Abioticfactorsthatinfluenceecosystemprocessesandspeciesdistributionsinclude
temperature,water,carbondioxide,nutrients,anddisturbanceregimes(Prenticeetal.1992,
Holling1992).Waterbalance,orthedifferencebetweenprecipitationinputsandwaterlossinthe
formofevapotranspiration,runoff,anddeepdrainage,isaprimarydeterminantofterrestrial
vegetationdistributionintheU.S.(Stephenson1990,Nielsonetal.1992,Nielson1995).
24ColoradoNaturalHeritageProgram©2015
Becausecompleteandaccurateknowledgeofdrivingfactorsandhistoryisrarely,ifever,available,
werelyoncorrelativemodelsthatrelateobservedspeciesdistributionwithpastandrecentlevels
ofclimaticvariables.Thepredictiveprocessisfurtherconstrainedbyourinabilitytomeasuresuch
variablesaccuratelyonacontinuousspatialortemporalscale.Asaresult,modelingvariablesare
usuallyanapproximationoftheenvironmentalfactorsthatcontrolspeciesdistribution,using
availabledatathatarelikelyonlysurrogatesfortheactualcontrollingfactors.Furthermore,
becausetherateofvegetationresponsetoenvironmentalshiftsislikelytobelowerthantherateof
climatechangeitself,andbecauserelictreesmayremainfordecades,predictivemodelsaremore
usefulinidentifyingthefuturelocationofsuitablehabitatforaspeciesthaninpredictingtheactual
groundcoverataspecifictimeinaparticularlocation.Finally,althoughwecanestimatethe
climaticrequirementsofagivenspecies,andextrapolatefromthatestimatetheeventual
distributionofanecosystem,itismoredifficulttopredictvegetationdynamicsthataretheresultof
disturbanceeventsorecologicalprocesses(e.g.,drought,fire,snowmelt,herbivory,insect
outbreaks,etc.).Thesefactorsareaddressednarratively,andevaluatedthroughexpertelicitation.
Becauseoftheselimitations,welookedatdegreeofchangeofclimaticvariablesoveran
ecosystem’scurrentrangeasameasureofexposuretoclimatechange,ratherthanattemptto
predictoverallchangesindistribution.
Exposure and sensitivity assessment – terrestrial ecosystems
Weusedspatialanalysismethodstoevaluatetheexposureandsensitivitytoclimatechangefor
eachecosystem.Weusedensembleaveragesof800mNASAEarthExchange(NEX)Downscaled
ClimateProjections(NEX‐DCP30)fortheContinentalUS.Theseaveragesarebasedon34models
developedfortheWorldClimateResearchProgramme's(WCRP)CoupledModelIntercomparison
ProjectPhase5(CMIP5).IndividualmodelsarelistedinAppendixA.
ThereisgeneralagreementthattemperaturesthroughoutColoradoareprojectedtoincrease.
Precipitationmodelsaremuchmorevariable,and,onaveragetendtoshowincreasing
precipitationformostofColorado.However,hydrologicmodelingfortheColoradoRiverandother
basins(e.g.,NashandGleick1991,1993)hasindicatedthat,asageneralizedrule‐of‐thumb,for
each1.8°F(1°C)ofwarming,anapproximate5%increaseinprecipitationwouldberequiredfor
runofflevelstoremainunchanged(SolidlineinFigure2.1).Withprojectedmid‐century
temperaturesincreasing4°Formore,noareasinColoradoareprojectedtoreceivesufficient
compensatoryprecipitation.Inordertoaccountforthepotentialeffectsofwarmertemperatures
onsoilmoistureavailability,anddeterminetheextenttowhicheachecosystemmaybeexposedto
effectivelydrierconditions,wemadeaconservativeapplicationoftheaboverule,toevaluatehow
muchofanecosystemmightreceiveatleastapartial(50%)levelofcompensatoryprecipitation
(dashedlineinFigure2.1).
ClimateChangeVulnerabilityAssessmentforColoradoBLM25
Figure 2.1.Statewideenvelopeofprojectedchangeinannualmeantemperatureandprecipitationundertwo
emissionsscenarios(boxes),incomparisonwithlevelsofprecipitationincreaserequiredtomaintainthestatus
quo.
Foreachecosystem,wecalculatedtheproportionofacreagewhereprojectedannualmean
temperatureformid‐centuryunderRCP8.5wasgreaterthananyannualmeantemperatures
currentlyexperiencedbythatecosystemwithinColorado,ANDprojectedfutureprecipitation
changeswerelessthan5%increaseovercurrentlevels.Ecosystemswerescoredaccordingtothe
scaleshownbelow(Table2.2).Inaddition,anyecosystemwhoseproportionofacreagewith
temperatureswithinthenormalrange,butwithmorethan50%ofthatacreagehavingprojected
futureprecipitationchangeswithlessthan5%increaseovercurrentlevels,wasbumpedtothe
nexthigherexposurecategory.
Itisimportanttonotethattheresultingscoresareintendedtogivearelative,notanabsolute
indicationofthepotentialimpactoffutureclimateconditionsonanecosystem.Thatis,a“Low”
scoredoesnotmeanthatanecosystemisnotvulnerabletoclimatechange,butthattheanalysis
indicatesthatitmaybelessvulnerablethanthoseecosystemswithscoresofModerate,High,or
VeryHigh.Furthermore,underthescoringsystemweused,“Moderate”isabroadcategory,andall
ecosystemswithaModeratevulnerabilityrankarenotnecessarilyequallyvulnerable.
Table 2.2.Criteriaforscoringexposureofterrestrialecosystems.
PercentColoradoacreswithprojected
temp>max&pptdelta<5%36–100%16–35%0–15%
InitialExposure‐SensitivityScoreHighModerateLow
PercentColoradoacreswithtemp<=
max&pptdelta<5%morethan50%?YesNoYesNoYesNo
FinalExposure‐SensitivityScoreVeryHighHighHighMod.ModLow
26ColoradoNaturalHeritageProgram©2015
Resilience‐adaptive capacity assessment – terrestrial ecosystems
Thisscoresummarizesindirecteffectsandnon‐climatestressorsthatmayinteractwithclimate
changetoinfluencetheadaptivecapacityandresilienceofanecosystem.Factorsevaluatedare
adaptedfromthemethodologyusedbyManometCenterforConservationScienceand
MassachusettsDivisionofFishandWildlife(MCCSandMAFW2010),combinedunderfiveheadings
(Table2.3).Factorswerescoredonascaleof0(lowresilience)to1(highresilience).
Table 2.3.Descriptionoffactorsusedtoassessresilience‐adaptivecapacityinterrestrialecosystems.
Assessment factor Description
Bioclimaticenvelopeandrange
Thisfactorsummarizestheexpectedeffectsoflimitedelevationalor
bioclimaticrangesforanecosystem.Suitableconditionsforecosystemsat
upperelevationsmaybeeliminated.Ecosystemswithnarrowbioclimatic
envelopesmaybemorevulnerabletoclimatechange.Finally,ecosystems
thatareatthesouthernedgeoftheirdistributioninColoradomaybe
eliminatedfromthestateunderwarmingconditions.
Growthformandintrinsic
dispersalrate
Thisfactorsummarizestheoverallabilityoftheecosystem’scomponent
speciestoshifttheirrangesinresponsetoclimatechangerelativelyquickly.
Characteristicsofgrowthform,seed‐dispersalcapability,vegetativegrowth
rates,andstress‐toleranceareconsidered.
Vulnerabilitytoincreased
impactbybiologicalstressors
Thisfactorsummarizeswhetherexpectedfuturebiologicalstressors
(invasivespecies,grazersandbrowsers,pestsandpathogens)havehad,or
arelikelytohave,anincreasedeffectduetointeractionswithchanging
climate.Climatechangemayresultinmorefrequentormoresevere
outbreaksofthesestressors.Ecosystemsthatarecurrentlyvulnerableto
thesestressorsmaybecomemoresounderclimatechange.
Vulnerabilitytoincreased
frequencyorintensityof
extremeevents
Thisfactorevaluatescharacteristicsofanecosystemthatmakeitrelatively
morevulnerabletoextremeevents(fire,drought,floods,windstorms,dust
onsnow,etc.)thatareprojectedtobecomemorefrequentand/orintense
underclimatechange.
Otherindirecteffectsofnon‐
climatestressors–landscape
condition
Thisfactorsummarizestheoverallconditionoftheecosystematthe
landscapelevelacrossColorado,andisderivedfromalandscapeintegrity
scoreindexingthedegreeofanthropogenicdisturbance(Rondeauetal.
2011,Lemlyetal.2011).
Bioclimatic envelope and range
Eachecosystemwasscoredforelevationalrange,southernedgeofrange,annualprecipitation
range,andgrowingdegreedaysrange.Ecosystemsrestrictedtohighelevationsreceivedascoreof
0,otherecosystemsscored1.Likewise,ecosystemsatthesouthernedgeoftheircontinentalrange
inColoradowereassignedascoreof0,andotherecosystemsscored1.Annualprecipitationand
growingdegreedaysrangewerecalculatedastheproportionoftotalvariablerangeinColoradoin
whichtheecosystemhadsignificantpresencemapped.Thesefourscoreswereaveragedtoproduce
asinglescoreforthisfactor.
ClimateChangeVulnerabilityAssessmentforColoradoBLM27
Growth form and intrinsic dispersal rate
Scoresof0(lowresilience),0.5(uncertainormoderateresilience),and1(highresilience)were
assignedtoeachecosystembasedongrowthformofthedominantspecies(i.e.,treesscored0,
shrubsandherbaceousscored1),andotherinformationderivedfromtheliteratureregardingthe
dispersalabilitiesofthosespecies.
Vulnerability to increased attack by biological stressors
Beginningwithadefaultscoreofone,wesubtracted0.2forvulnerabilitytopotentialincreased
effectsofgrazersorbrowsers,and0.3forvulnerabilitytoinvasivespecies.Inaddition,foresttypes
withlevelsofinsectmortalitysufficienttocausedramaticstructuralchangesoveralargearea(>1
millionacresinColorado)receivedascoreof0,andforesttypeswithlowerlevelsofinsect
mortalityreceivedastartingscoreof0.7.Forestscoringwasbasedoncumulativedamagetotals
fromUSFSAerialSurveys(USDAForestService2014).
Vulnerability to increased frequency or intensity of extreme events
Ecosystemsnotespeciallyvulnerabletoincreasedfrequencyorintensityofabioticstressors
receivedadefaultscoreofone.Foresttypesnotadaptedtodryconditionswerescored0.5,to
accountforincreasedsusceptibilitytothecombinedeffectsofdroughtandpotentiallyincreased
wildfire,whilemoredroughttolerantforesttypesscored0.7.Non‐forestecosystemsvulnerableto
droughtwerescored0.5,andecosystemsvulnerableonlytootherabioticstressorsscored0.9.
Landscape condition
Theaveragevalueacrossthestatewidelandscapeintegritymodels(Rondeauetal.2011,Lemlyet
al.2011)foreachecosystemwascalculatedasavaluebetween0and1.
Resilience‐adaptive capacity ranking
Scoresforthefivefactorsarebasedonbothspatialanalysisandliteraturereview.Rankingsforthis
sub‐scoreareoppositetothedirectionoftheexposure‐sensitivityrankingscheme(i.e.,ahigher
valueindicates“better”andalowervalueindicates“worse.”)Theroundedaverageofthefivesub‐
scoresdeterminesthefinalResilience‐AdaptiveCapacityscore.
AverageofResilience‐AdaptiveCapacityScores0–0.500.51–0.700.71–1.0
OverallResilience‐AdaptiveCapacityScoreLowModerateHigh
Vulnerability assessment ranking
Overall vulnerability ranking
TheExposure‐SensitivityscoreandtheResilience‐AdaptiveCapacityscorearecombined(Figure
2.2)accordingtotheschemepresentedbelow(Comeretal.2012)toproduceanoverall
vulnerabilityrankforeachecosystem.
28ColoradoNaturalHeritageProgram©2015
Exposure‐Sensitivityscore/Resilience
‐AdaptiveCapacityscore
Vulnerability
H/HM/HL/H
VeryHigh
High
Moderate
Low
H/MM/ML/M
H/LM/LL/L
Figure 2.2.Vulnerabilityrankingmatrix.
VeryHigh:Ecosystemshavehighvulnerabilitytoclimatechangewhenexposureand
sensitivityarehigh,andadaptivecapacityandresiliencearelow.Underthesecircumstances,
transformationoftheecosystemismostlikelytooccurinupcomingdecades.
High:Highvulnerabilitytoclimatechangeresultsfromcombiningeitherhighormoderate
exposure‐sensitivitywithlowormediumadaptivecapacity‐resilience.Undereither
combination,climatechangeislikelytohavenoticeableimpact.
Moderate:Moderatevulnerabilitytoclimatechangeresultsfromavarietyofcombinationsfor
exposure‐sensitivityandadaptivecapacity‐resilience.Thescoringmatrixisslightlyweighted
towardincreasedvulnerabilityinthenumberofpossiblecombinationswhichproducea
moderatevulnerabilityranking.Undercircumstanceswherethetwofactorsareessentially
balanced,vulnerabilityisthoughttobereduced,butstillofconcern.
Low:Lowvulnerabilitytoclimatechangeoccurswhenanecosystemisexpectedtoexperience
lowexposureandsensitivityincombinationwithhighormoderateadaptivecapacityand
resilience.Fortheseecosystemsclimatechangestressanditseffectsareexpectedtobeleast
severeorabsent.
ClimateChangeVulnerabilityAssessmentforColoradoBLM29
TERRESTRIAL ECOSYSTEMS ‐ RESULTS
Overview of terrestrial ecosystems
Change in temperature and precipitation by mid‐century
Underthemostseverescenarioecosystemsevaluatedhereinareprojectedtoexperienceannual
meantemperaturesthatare5‐6°Fwarmerthanintherecentpast;atthesametimefuture
precipitationlevelsarenotprojectedtoincreasesufficientlytocompensateevenpartiallyfor
increasedmoisturelossduetowarmertemperatures(dashedlineinFigure2.3).
Figure 2.3.ProjectedannualchangeinColoradofor(a)uplandecosystems,and(b)wetlandandriparian
ecosystems.Ecosystemmeansarecoloredtoindicatethedegreetowhichtheecosystemisprojectedto
experienceconditionsthatareoutofrangeofthoseinitscurrentstatewidedistribution.
Resilience factors
ResultsforindividualresiliencefactorsareshowninFigure2.4anddiscussedindetailbelow.

30ColoradoNaturalHeritageProgram©2015
(a)Range&environmentalenvelope
rank
(b)Dispersal&growthformrank(c)Biologicalstressorsrank
(d)Abioticstressors&Extremeevents
rank
(e)Landscapeconditionrank(f)OverallResilience‐Adaptive
capacityrank
Figure 2.4.Comparisonofscoresbyecosystemfor(a‐e)individualresiliencefactors,and(f)overallresilience–
adaptivecapacityscore.Backgroundcolorsreflectthelow(red),moderate(orange),andhigh(green)resilience
categories.
Elevation range and relative abundance
Togetherwithrangeextentandbioclimateenvelope(below),weconsideredelevationasafactor
thatmightdetractfromtheresilienceofanecosystem.EcosystemelevationsinColoradorange
fromabout3,500fttonearly14,000ft(Figure2.5).Theextremehighestelevationsarenon‐
vegetated.Lowelevationsareoccupiedbygrassland,shrubland,andwoodlandecosystems
dominatedbyspeciesadaptedtolowerprecipitationandwarmconditions.Anumberofmontane
tosub‐alpineecosystemsareclusteredtogetheratmiddleelevationsfromabout7,000‐10,000ft.At
higherelevations,subalpineforestandalpinevegetationoccupyfairlydistinctelevationalzones.
ClimateChangeVulnerabilityAssessmentforColoradoBLM31
Figure 2.5.AreaofecosystemsmappedatvariouselevationsinColorado.
Bioclimatic envelope
Temperatureandprecipitationvariableswereusedtocharacterizethecurrentbioclimatic
envelopeforeachterrestrialecosystem.Acombinedprecipitationandtemperaturespaceisshown
foreachofthe14uplandecosystemsinFigure2.6.Becauseprecipitationandtemperatureare
highlycorrelatedwithelevation,patternsaresimilartothoseshownunderelevationrangeabove.
Desertshrublandoccupiesthedriestbioclimaticenvelope,whilesandsageandshortgrassprairie
arethewarmest.Statewide,ponderosa,oak‐shrubandsagebrushshrublandarecloselyrelatedin
bioclimaticspace,andshowsubstantialoverlapwiththewarmeranddrierpinyon‐juniperand
semi‐desertgrassland.Abovethesewarmeranddrierecosystems,mixedconifer,aspen,and
lodgepoleforestshareamid‐elevationenvelopewithmontanegrasslands.Thecoldest,wettest
environmentsareoccupiedbyalpinetypes,withspruce‐firforestintermediatebetweenthemiddle
groupandthesehabitats.
Historictemperaturerangesforwinterminimumsandsummermaximumsforeachupland
ecosystemareshowninFigure2.7,andillustratethesamerelationshiptoelevationasdotheother
climatevariables.ThegeographicareacurrentlyoccupiedbyeachecosysteminColoradoislikelyto
experienceashifttowardwarmertemperatures,withtheresultthatbioclimaticenvelopeswillshift
towardhigherelevations.Theacreagethatfallswithinaparticulartemperaturerangewillbe
reducedforcoolertemperaturesandincreasedforwarmertemperatures.
32ColoradoNaturalHeritageProgram©2015
Theoverallelevation,range,andbioclimateenveloperesultsareshowninFigure2.4a.
Figure 2.6.Bioclimaticenvelopeasrepresentedbyannualprecipitationandmeantemperatureforecosystemsin
Colorado.Errorbarsrepresentthe10‐90%rangearoundthemean.
ClimateChangeVulnerabilityAssessmentforColoradoBLM33
Figure 2.7.MinimumwinterandmaximumsummertemperaturerangesforecosystemsinColorado.Boxes
representthemiddlequartiles,whilewhiskersshowthe10‐90%range.
Intrinsic dispersal rate
Mostcharacteristicspeciesofforestorwoodlandecosystemsdonotproducelargenumbersof
seedlingsorspreadquicklyviavegetativegrowth.WiththeexceptionofaspenandGambeloak,
forestandwoodlandtreespeciesaretypicallyslowgrowing,withlimiteddispersalability.Past
migrationratesforNorthAmericantreespeciesinthecurrentinterglacialhavebeenestimatedat
tenstoseveralhundredsofmetersperyear.Althoughthecurrentlyobserveddistributionofa
speciesislikelytolagbehindcurrentclimateconditions,futureconditionsarepredictedtorequire
migrationratesonetofivekilometersperyearinorderforspeciestokeepupwithsuitablehabitat
conditions(Roberts2013).Shrubandgrass‐dominatedecosystemsaresomewhatbetteradaptedto
spreadintoavailablehabitatthroughrelativelyrapidvegetativegrowth.Barrierstoecosystem
movementinColoradoareprimarilythoseduetoelevationalgradientsorhabitatfragmentation,
althoughsoiltypeislikelytoinfluencedispersalandestablishmentpatternsthroughvariable
water‐holdingcapacity.EcosystemranksforthisfactorareshowninFigure2.4b.
34ColoradoNaturalHeritageProgram©2015
Biological stressors
BiologicalstressorsforecosystemsinColoradoincludeforestpestsandpathogens,invasive
species,incompatibledomesticlivestockgrazing,andchangesinpatternsofnativeungulate
herbivory.EcosystemranksforthisfactorareshowninFigure2.4c.
Nativeinsectsthatcausetreedamageandmortalityincludebarkbeetles(Dendroctonusspp.,Ips
spp.),westernsprucebudworm(Choristoneuraoccidentalis),andtentcaterpillars(Malacosoma
spp.).Armillariarootdiseaseisasignificantcauseofmortalityinconiferspecies.Pinyonare
susceptibletothefungalpathogenLeptographiumwagenerivar.wageneri,whichcausesblackstain
rootdisease.Five‐needlepines,includinglimberandbristlecone,arethreatenedbywhitepine
blisterrust(WPBR)infectioncausedbytheintroducedfungusCronartiumribicola.
Exoticinvasiveplantspecieswiththepotentialtoalterecosystemfunctioningthatareregionally
widespreadinColoradoincludecheatgrass(Bromustectorum),knapweed(Acroptilonand
Centaureaspp.)Russianolive(Elaeagnusangustifolia)leafyspurge(Euphorbiaesula),andtamarisk
(Tamarixramosissima).Canadathistle(Cirsiumarvense)andmuskthistle(Carduusnatans)arealso
widespread,andother,lessprevalentproblemspeciesincludeoxeyedaisy(Leucanthemum
vulgare)andyellowtoadflax(Linariavulgaris).Mountaingrasslands,lowelevationshrubland,and
riparian/wetlandecosystemsaremostaffected.
Togetherwithlivestockgrazing,overabundanceofnativeungulates(e.g.,deerandelk)andferal
burrosorhorsescanaltervegetation,soils,hydrology,andwildlifespeciescompositionand
abundancesinwaysthatintensifytheeffectsofclimatechangeontheseresources(Beschtaetal.
2013).Forterrestrialecosystems,theprojectedcombinationofincreasingdrought,higher
temperatures,earliersnowmelt,andprecipitationvariabilityinteractingwiththeeffectsof
ungulateusecanresultindecreasedbiodiversity,reducedsoilmoisture,acceleratedsoiland
nutrientloss,andincreasedsedimentation(Beschtaetal.2013).
Extreme events
Extremeeventsthatmayincreaseinfrequencyand/orseverityunderchangingclimaticconditions
includedrought,wildfire,flooding/erosion,andwindstorms.Ecosystemranksforthisfactorare
showninFigure2.4d.
ProlongeddroughthasbeenaperiodicinfluenceinthewesternUnitedStates,includingColorado
(Woodhouse2004).Ecosystemsoflowerelevationsaregenerallydroughttolerant,although
speciescompositionwithinanecosystemislikelytoshiftwithchangingclimatepatterns.Although
wescoredvulnerabilitytoabioticeventsasdistinctfrombiologicalstressors,theinteractionof
wildfireanddroughtwiththeeffectsofthesefactors,especiallyforestmortalityagentslikebark
beetles,blursthedistinctionsomewhat.ThespeciesthatcharacterizeColorado’secosystemshave
varyingtolerancetodrought,however,itislikelythatallspeciesarelessresistanttotheeffectsof
herbivory,pests,andpathogenswhenunderdroughtstress.Widespreadprevalenceofdrought‐
stressedtreesmayprovideenhancedconditionsforstand‐replacingeventssuchasfireorinsect
outbreak(DeRoseandLong2012).Ecosystemsofhigher,wetterelevationshavegenerallybeen
“climate‐limited,”withhighfuelloads,butrarelyhavingdryclimateconditionssuitableforfire
ClimateChangeVulnerabilityAssessmentforColoradoBLM35
spread.Lower,moremesicecosystemshavebeencharacterizedas“fuel‐limited,”withconditions
frequentlysuitableforfire,butlowfuelloadsunlessprioryearshavebeenwet(Whitlocketal.
2010).Withwarmertemperaturesandmorefrequentdrought,higherelevationforestswith
abundantfuelsmayhaveincreasedfirefrequency,whilelowerelevationgrasslandandshrubland
ecosystemsbecomemorefuel‐limitedwithreducedbiomassproduction(Arnoldetal.2014).
Althoughtherearenooverallprecipitationincreasetrendsassociatedwithrecentwarming,there
isevidencethatextremeprecipitationeventshaveincreasedinfrequencyoverthepastseveral
decades(Walshetal.2014).Warmerairandoceantemperaturesallowtheatmospheretohold
moremoisture,whichcanresultinheavyprecipitation,causingmoreextremefloodinganderosion
events,evenifannualprecipitationtotalsdecline.Althoughfuturetrendsinstormoccurrenceare
uncertain,anincreaseinfrequencyofseverestormscouldincreasethefrequencyofwindthrow
eventsinforestedareas.
Non‐climate abiotic stressors
Thecombinedeffectsofhumanactionsthatfragmentlandscapes,alternaturalprocesses,reduce
biodiversity,anddegradeenvironmentalqualityarelikelytoreducetheresilienceofcomplex
adaptiveecosystemstoregimeshiftsunderchangingclimateconditions(Folkeetal.2004).The
cumulativeeffectsofanthropogenicdisturbanceinColoradoareduetohabitatfragmentationand
conversionduetoagriculturaluseaswellasindustrial,residential,resource,andrecreational
developmentactivities.Ourscoringassumesthatecosystemswithhigherlevelsofanthropogenic
disturbancearelikelytobelessresilienttodisturbanceofanykindunderfutureclimateconditions.
Ecosystemsofthehighestelevations,whicharegenerallyinpublicownership,hadthehighest
resilienceratingforthisfactor,whileecosystemsofvalleybottoms,orthoseotherwisefragmented
bylandusehadpoorresilienceratings(Figure2.4e).
Ecosystem vulnerability ranks
Fourofthe20ecosystemsorregionalecosystemsubgroupsassessedhaveanoverallvulnerability
rankofHigh,andoneisrankedVeryHigh(Table2.4).Ingeneral,ecosystemsoftheeasternplains
havethegreatestexposuretochange,andthoseofhigherelevationshavelowerexposure.Undera
longertime‐frame,highelevationareaswouldbesubjecttoincreasedexposure.Mostecosystems
wereassessedashavingmoderateresilience.Asummaryofclimatechangevulnerabilityanalysis
(CCVA)detailsforeachecosystemisprovidedbelow,beginningonpage42.
36ColoradoNaturalHeritageProgram©2015
Table 2.4.Vulnerabilityranksummaryforallassessedterrestrialecosystems.
Ecosystem Target
Exposure ‐
Sensitivity final
ranking
Resilience ‐
Adaptive Capacity
final ranking
Combined
ranks
Overall
vulnerability
rank
Forest and Woodland
AspenforestLowHighL/HLow
LodgepolepineforestLowLowL/LModerate
MixedconiferforestModerateModerateM/MModerate
Pinyon‐JuniperwoodlandModerateLowM/LHigh
PonderosapineforestModerateModerateM/MModerate
Spruce‐FirforestLowLowL/LModerate
Shrubland
DesertshrublandModerateModerateM/MModerate
Oak&mixedmountainshrub LowHighL/HLow
SagebrushshrublandLowModerateL/MLow
SandsageshrublandHighHighH/HModerate
Grassland or Herbaceous
AlpineLowModerateL/MLow
MontanegrasslandModerateHighM/HModerate
Semi‐desertgrasslandLowHighL/HLow
ShortgrassprairieHighModerateH/MHigh
Riparian & Wetland
Riparianwoodland&shrubland‐eastHighModerateH/MHigh
Riparianwoodland&shrubland‐mountainLowModerateL/MLow
Riparianwoodland&shrubland‐westHighLowH/LVery High
Wetlands‐eastHighModerateH/MHigh
Wetlands‐mountainModerateModerateM/MModerate
Wetlands‐westModerateModerateM/MModerate
Conclusions
Allecosystemsarelikelytobeaffectedtosomeextentbyclimatechange.Ecosystemswithlow
exposureandhighresiliencecouldbethebeneficiariesoffutureconditions,whilethosewithhigh
exposureandlowresiliencearelikelytoexperiencerangecontractionsand/orsignificantchanges
inspeciescompositionandoverallcondition.Themajorityofhabitattypeswererankedwithlowor
moderatevulnerabilityinouranalysis,however,thegradationsofmoderatelyvulnerable,andthe
transitiontohighlyvulnerablearelessclearthantheseparationbetweenlowandmoderate
vulnerability.Themethodsusedtocombineestimatedexposureandresiliencescoresleavealarge
ClimateChangeVulnerabilityAssessmentforColoradoBLM37
middlegroundwhichcanbeaffectedbyuncertaintyinclimateprojections,currentknowledge,and
ongoingmanagementactions.
Bymid‐century,underbothmoderateandhighradiativeforcingscenarios(RCP4.5andRCP8.5),we
canexpecttoseewarmertemperaturesstatewide,especiallyontheeasternplains.Warmer
temperaturesarelikelytoincludemoreheatwaves,fewercoldsnaps,andgenerallyextendedfrost‐
freeperiods.Althoughtheseconditionscouldbenefitmanyspeciesifprecipitationremains
adequate,thewarmingtrendislikelytobeaccompaniedbyeffectivelydrierconditionsinmany
areas.Evenifprecipitationlevelsathigherelevationsareessentiallyunchanged,warmer
conditionswillleadtomoreprecipitationfallingasraininsteadofsnow,adecreasedsnowpack,
earlierrunoff,andearlierdryconditionsinlatesummer(Lucasetal.2014).Allofthesefactorsmay
interactwithstressorssuchasfire,forestpestsanddiseases,drought,andanthropogenic
disturbancetoalterthefuturetrajectoryofaparticularecosystem.
Comparisonoftherecenthistoricalvaluesofclimatevariableswithprojectedvalueswithinthe
currentColoradodistributionoftheterrestrialecosystems(Figures2.8and2.9)indicatesseasonal
differencesindegreeanddirectionofprojectedchangesintemperatureandprecipitation.For
instance,ecosystemsofhigherelevationsareprojectedtoexperienceagreaterincreaseinwinter
precipitationthanthoseoflowerelevations,althoughtheamountofwarmingissimilarforall
elevations.Projectedchangesinsummerprecipitationaregenerallylessthanforwinter,withsome
ecosystemsseeingaslightincreaseandothersaslightdecrease.
Theinteractionofclimaticconditionswithotherenvironmentalfactorsandbiogeographichistory
shapesthedistributionofecosystemsthatwecurrentlyobserve.Furthermore,thetimelag
betweenwhenclimateconditionsbecomesuitableorunsuitableforaspeciesandtheeventual
colonizationoreliminationofthatspeciesinanareaaddsanotherlevelofuncertaintyto
projectionsoffuturedistribution.Climatechangesoverthepastfewdecadesareprobablyalready
facilitatingagradualshiftofecosystemsthatwillbecomemoreapparentbymid‐century.
Ouranalysisoftherangeoffutureuncertaintyfocusedon“worstcase”(RCP8.5)outcomesinorder
toprovideavulnerabilityprioritizationofkeyecosystemsthatwillfacilitateapragmatic“no‐
regrets”planningstrategyforBLMstaffdealingwiththeongoingeffectsofclimatechangein
Colorado.

38ColoradoNaturalHeritageProgram©2015
Figure 2.8.Projectedseasonalaverageprecipitationandmeantemperaturetrajectoriesforcurrentupland
ecosystemrangesinColoradobymid‐centuryunderahighradiativeforcingscenario(RCP8.5).Circlesrepresent
currentconditions.
ClimateChangeVulnerabilityAssessmentforColoradoBLM39

Figure 2.9.Projectedseasonalaverageprecipitationandmeantemperaturetrajectoriesforcurrentwetlandand
riparianecosystemrangesinColoradobymid‐centuryunderahighradiativeforcingscenario(RCP8.5).Circles
representcurrentconditions.
40ColoradoNaturalHeritageProgram©2015
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
42ColoradoNaturalHeritageProgram©2015
TERRESTRIAL ECOSYSTEM CCVA SUMMARIES
Forest and Woodland
Table 2.5.Keyvulnerabilities,forestandwoodlandecosystems.
Habitat Climate factor(s) Consequences Other considerations
AspenWarmeranddryconditionsAspendecline,especiallyat
lowerelevations
Maybenefitfromfire
increase,smallpatchesin
coniferforestmayexpand
afterconifermortality
LodgepoleDrought,warmer
temperatures
Fireandinsectoutbreak;
rangecontraction

MixedConiferWarmeranddryconditionsChangeinrelativespecies
abundanceorconversionto
othertype
Diversespeciescomposition
makesitlikelythatsome
specieswillthrive
Pinyon‐juniperWarmeranddryconditionsChangeinrelativespecies
abundancefavoringjuniper;
fireandinsectoutbreak;
reducedpinyonpinecone
production
Soiltypesaffectdistribution
PonderosaDroughtFireandinsectoutbreakWildland‐UrbanInterface
complicatedmanagement
Spruce‐firDroughtFireandinsectoutbreakSlowdispersal,short
growingseasonincreases
vulnerabilityovertime
ClimateChangeVulnerabilityAssessmentforColoradoBLM43
ASPEN
Forestsandwoodlandsdominatedbyquakingaspen
R.Rondeau
extentexaggeratedfordisplay
Climate Vulnerability Rank: Low
Vulnerability summary
Key Vulnerabilities:Hotanddryconditionsarelikelytoleadtoaspendeclineandmortalityatthe
lowestelevations.However,smallaspenpatchesinconiferforestmaybenefitfromfireincreaseand
expandfollowingconifermortality.
Overallexposuretowarmerandeffectivelydrierconditionsis
lowforthisecosysteminColorado;standsatlowerelevationsare
mostatrisk.Theseforestsaremoderatelyresilient,andin
generallygoodcondition.Aspendynamicsarevariableacrossthe
west,dependingonbothspatialandtemporalscales
(Kulakowski,Kaye,andKashian2013);asaresultthereismuch
uncertaintyaboutthefuturedistributionofthisspecies.Low
elevationstandsimpactedbydroughtarelikelytoexperience
dieback,butinotherareastheinteractionofchangingclimate
anddisturbanceregimesmayfavoraspen(Kulakowski,
Matthews,Jarvis,andVeblen2013).
Distribution
Quakingaspen(Populustremuloides)hasthelargestdistributionofanytreenativetoNorth
America(Little1971).Therangeofthisspecieshasexpandeddramaticallysincetheendofthelast
glacialmaximum,duringwhichthegreaterpartofitsrangewascoveredbytheCordilleranand
Laurentideicesheets.ThiswidespreadecosystemoccursthroughoutmuchofthewesternU.S.and
44ColoradoNaturalHeritageProgram©2015
northintoCanada,althoughitismorecommoninthemontaneandsubalpinezonesofthesouthern
andcentralRockyMountains.Theseareuplandforestsandwoodlandsdominatedbyquaking
aspen,orforestsofmixedaspenandconifer,occurringasamosaicofvaryingplantassociations
andadjacenttoadiversearrayofotherecosystems,includingmontanegrasslandsandshrublands,
wetlands,andconiferousforests.InColoradothissystemrangesinelevationfromabout7,500to
10,500feet,andisquitecommononthewestslope,withsmallerstandsrepresentedontheeast
slope.
Characteristic species
Theseforestshaveasomewhatclosedcanopyoftreesof15‐65ft(5‐20m)tall,dominatedby
quakingaspen.Afewconifersmaybepresentincludingwhitefir(Abiesconcolor),subalpinefir
(Abieslasiocarpa),Engelmannspruce(Piceaengelmannii),bluespruce(Piceapungens),ponderosa
pine(Pinusponderosa,)andDouglas‐fir(Pseudotsugamenziesii).Ifconifersmakeupmorethan
15%ofthetreecanopytheoccurrenceisgenerallyconsidereamixedconiferstand.
Theaspencanopytypicallyallowssufficientlightpenetrationforthedevelopmentofalush
understory.Understoriesarehighlyvariableandmaybedominatedbyshrubs,graminoids,or
forbs.CommonshrubsincludeRockyMountainmaple(Acerglabrum),Saskatoonserviceberry
(Amelanchieralnifolia),mountainbigsagebrush(Artemisiatridentatassp.vaseyana),common
juniper(Juniperuscommunis),chokecherry(Prunusvirginiana),Wood’srose(Rosawoodsii),russet
buffaloberry(Shepherdiacanadensis),mountainsnowberry(Symphoricarposoreophilus),andthe
dwarf‐shrubscreepingbarberry(Mahoniarepens)andwhortleberry(Vacciniumspp.).Common
graminoidsincludepinegrass(Calamagrostisrubescens),dryspikesedge(Carexsiccata),Geyer's
sedge(Carexgeyeri),Ross'sedge(Carexrossii),bluewildrye(Elymusglaucus),slenderwheatgrass
(Elymustrachycaulus),Thurberfescue(Festucathurberi),andneedle‐and‐thread(Hesperostipa
comata).ExoticgrassessuchastheperennialsKentuckybluegrass(Poapratensis)andsmooth
brome(Bromusinermis)andtheannualcheatgrass(Bromustectorum)areoftencommonin
occurrencesdisturbedbygrazing.Associatedforbsmayincludecommonyarrow(Achillea
millefolium),Engelmann'saster(Eucephalusengelmannii),larkspur(Delphiniumspp.),Richardson's
geranium(Geraniumrichardsonii),commoncowparsnip(Heracleummaximum),Porter'slicorice‐
root(Ligusticumporteri),silverylupine(Lupinusargenteus),sweetcicely(Osmorhizaberteroi),
westernbrackenfern(Pteridiumaquilinum),Fendler'smeadow‐rue(Thalictrumfendleri),western
valerian(Valerianaoccidentalis),Americanvetch(Viciaamericana),mule‐ears(Wyethia
amplexicaulis),andmanyothers.
Environment
Rangewideelevationsgenerallyrangefrom5,000‐10,000feet(1,525to3,050m),butcanbelower
insomeregions.Topographyisvariable,sitesrangefromleveltosteepslopes.Occurrencesathigh
elevationsarerestrictedbycoldtemperaturesandarefoundonwarmersouthernaspects.Atlower
elevationsoccurrencesarerestrictedbylackofmoistureandarefoundoncoolernorthaspectsand
mesicmicrosites.Thesoilsaretypicallydeepandwelldevelopedwithrockoftenabsent,and
texturerangesfromsandyloamtoclayloams.Parentmaterialsarevariableandmayinclude
sedimentary,metamorphicorigneousrocks,butthistypeappearstogrowbestonlimestone,
basalt,andcalcareousorneutralshales(Mueggler1988).
ClimateChangeVulnerabilityAssessmentforColoradoBLM45
Distributionofaspenforestisprimarilylimitedbyadequatesoilmoisturerequiredtomeetitshigh
evapotranspirationdemand,andsecondarilyislimitedbythelengthofthegrowingseasonorlow
temperatures.Climateistemperatewitharelativelylonggrowingseason,typicallycoldwinters
anddeepsnow.Meanannualprecipitationisgreaterthan15in(38cm)andtypicallygreaterthan
20in(50cm),exceptinsemi‐aridenvironmentswhereoccurrencesarerestrictedtomesic
micrositessuchasseepsorareasthataccumulatelargesnowdrifts.
Dynamics
Aspenisextremelyshadeintolerant,andabletoestablishquicklyoveradisturbedopenareadueto
itsabilitytoreproducebyvegetativesprouting(Howard1996).Thetuftedseedcapsulesproduced
bymatureaspentreesareamenabletowinddispersaloveraconsiderabledistance.Although
quakingaspenestablishmentfromseediscommoninAlaska,northernCanadaandeasternNorth
America,thisislesstrueinthewesternUS,probablybecausegerminatedseedlingsdonotreceive
sufficientmoistureforsurvival(Kay1993).Thereisconflictingevidenceforthefrequencyof
seedlingestablishmentinthewesternUS,however,andquakingaspenmayestablishfromseed
morefrequentlythanpreviouslythought(Howard1996,Rommeetal.1997).
Thereissomeevidenceforsynchronousaspenstandestablishmenteventsoveralargeareaofthe
intermountainwest.Kaye(2011)identifiedtwopeakperiodsofestablishmentviasexual
reproduction,thefirstintheperiod1870‐1890,andtheotherin1970‐1980.Shespeculatesthatthe
earlierestablishmenteventmaybethelegacyofthelastlargefireeventsbeforewidespreadfire
suppressionintheintermountainwest.Thesecondestablishmentpeakcorrespondswithimproved
moistureconditionsduetoashiftinthePacificDecadalOscillationandtheAtlanticMultidecadal
Oscillation.ElliotandBaker(2004)foundthataspenstandsintheSanJuanMountainsare
regeneratingandincreasingindensity.Furthermore,theybelievethataspenincreaseattreelineis
occurringasaresultofestablishmentfromseed.Althoughquakingaspenproducesabundantseeds,
seedlingsurvivalisrarebecausethelongmoistconditionsrequiredtoestablishthemarerarein
thesehabitats.Superficialsoildryingwillkillseedlings(Knight1994).
Aspenforestsandwoodlandsoftenoriginatefrom,andarelikelymaintainedby,stand‐replacing
disturbancessuchascrownfire,diseaseandwindthrow,orclearcuttingbymanorbeaver.The
stemsofthesethin‐barked,clonaltreesareeasilykilledbygroundfires,buttheycanquicklyand
vigorouslyresproutindensitiesofupto30,000stemsperhectare(Knight1994).Thestemsare
relativelyshort‐lived(100‐150years),andtheoccurrencewillsucceedtolonger‐livedconifer
forestifundisturbed.Occurrencesarefavoredbyfireintheconiferzone(Mueggler1988).With
adequatedisturbanceaclonemaylivemanycenturies.
Althoughaspenisnotfiretolerant,itishighlycompetitiveinburnedareasifotherconditionsare
suitable.Aspenclonessurviveintheunderstoryofcool,moistmixedconiferandlowelevation
spruce‐fir,andcanrespondquicklytodisturbances.Instandsaffectedbymultipledisturbance
types(e.g.fire,blowdown,beetle‐kill),aspenregenerationmaybefavoredoverthatofconifers
(Kulakowski,Matthews,Jarvis,andVeblen2013).
46ColoradoNaturalHeritageProgram©2015
CCVA Scoring
Exposure‐Sensitivity (Potential Impact) Rank
PercentColoradoacreswithprojectedtemp>max&pptdelta<5%0.2%
InitialExposure‐SensitivityRankLow
PercentColoradoacreswithtemp<=max&pptdelta<5%morethan50%?No(36.0%)
FinalExposure‐SensitivityRankLow
Exposuretotemperaturechange
Underprojectedmid‐centurytemperatures,lessthan1%ofthecurrentrangeofaspenforestin
Coloradowouldexperienceannualmeantemperaturesabovethecurrentstatewidemaximum.
Exposuretoprecipitationchange
About36%ofaspenforestecosysteminColoradowillbeexposedtoeffectivelydrierconditions
evenunderunchangedorslightlyincreasedprecipitationprojectedformid‐century.
Sensitivityofecosystemtotemperatureandprecipitation
Quakingaspenisabletogrowonawidevarietyofsites,bothdryandmesic(Mueggler1988).
Climaticconditions,inparticularminimumwintertemperaturesandannualprecipitationamounts
arevariableovertherangeofthespecies(Howard1996).Ingeneral,quakingaspenisfoundwhere
annualprecipitationexceedsevapotranspiration,andthelowerlimitofitsrangecoincideswitha
meanannualtemperatureof45°F(Perala1990).InthecentralRockyMountains,quakingaspen
distributionishighlycorrelatedwithelevation,duetoitsinfluenceontemperatureand
precipitationpatterns.IntheRockyMountainsstandsgenerallyoccurwhereannualprecipitationis
greaterthan14.9in(38cm)peryear(MorelliandCarr2011)andsummertemperaturesare
moderate.
Resilience and Adaptive Capacity Rank
OverallScore: 0.71Rank: High
Bioclimaticenvelopeandrange
Averagedcategoryscore:0.76
Aspenforestsarenotfoundatalpineelevations,butstandsarecommonthroughoutcentraland
westernColoradoatmontanetosubalpineelevations.Aspenforestshavesignificantpresencein
63%ofColorado’soverallprecipitationrange,andin40%ofthestate’sgrowingdegreedaysrange.
QuakingaspenisverywidelydistributedinNorthAmerica,andthesouthernlimitofitsrangeis
currentlywelltothesouthofColorado.
Growthformandintrinsicdispersalrate
Score:0.50
ClimateChangeVulnerabilityAssessmentforColoradoBLM47
Quakingaspenisarelativelyfastgrowingspecies,andabletoquicklycolonizedisturbedareasby
vegetativereproduction.However,duetoitstreegrowthform,anduncertaintyaboutseed
dispersalrates,thisecosystemwasscoredashavingintermediateresilienceinthiscategory.
Vulnerabilitytoincreasedattackbybiologicalstressors
Score:0.8
Vulnerabilityofaspentopathogensandherbivores,andsubsequentaspenmortalitymaybe
increasedbyclimatechangeifdroughtandwarmerconditionsincreaseenvironmentalstress
(MorelliandCarr2011).Heavygrazingbyelkincombinationwithdroughtappearstobeleadingto
declineinsomeareas(MorelliandCarr2011).Stressfromgrazingcouldbemitigatedby
managementactions.Cankerinfections,gypsymoth,andforesttentcaterpillaroutbreaksare
tightlyassociatedwithdrierandwarmerconditions(CryerandMurray1992,Johnston2001,Logan
2008,Hoggetal.2001).
Vulnerabilitytoincreasedfrequencyorintensityofextremeevents
Score:0.7
Aspenshaveincreasedsusceptibilitytoepisodicdeclineatlowerelevations,underwarmanddry
conditions(Worralletal.2008).Thisaspendieback(sometimescalledSuddenAspenDecline)
appearstoberelatedtodroughtstress,andistypicallygreatestonthehotteranddrierslopes,
whichareusuallyatthelowestelevationsofastand(Rehfeldtetal.2009).Standsmayundergo
thinning,butthenrecover.Increasingdroughtwithclimatechangeisbelievedtobetheprimary
vulnerabilityofthisecosystem(Worralletal.2013),andsubstantiallossofthistypecanbe
expected.Theeffectsofdroughtarelikelytointeractwithotherstressorssuchasoutbreaksof
pestsanddisease,snowmelttiming,andungulateherbivory.
Theinteractionofclimatechangewithnaturaldisturbancemayalsoaffectthefuturedistributionof
aspen.Althoughaspenisnotfiretolerant,itislikelytoestablishinadjacentforeststhathave
burned,ifotherconditionsaresuitable.
Otherindirecteffectsofnon‐climatestressors–landscapecondition
Score:0.77
AspenforestsinColoradoareingoodconditionandnothighlythreatened.MuchofColorado’s
aspenforestisonfederallandsmanagedbytheU.S.ForestService.Primaryhumanactivitiesinthis
ecosystemincludecattleandsheepgrazing,recreation,andhunting.Someaspenstandsarecutfor
timberproducts.Threatstotheaspenforestsandwoodlandsarecomparativelylow.
Literature Cited
Cryer,D.H.andJ.E.Murray.1992.Aspenregenerationandsoils.Rangelands14(4):223‐226.
Elliot,G.P.andW.L.Baker.2004.Quakingaspen(PopulustremuloidesMichx.)attreeline:acenturyofchangeintheSan
JuanMountains,Colorado,USA.JournalofBiogeography31:733‐745.
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Hogg,E.H.2001.ModelingaspenresponsestoclimaticwarmingandinsectdefoliationinwesternCanada.In:Shepperd,
W.D.;Binkley,D.;Bartos,D.L.;Stohlgren,T.J.;Eskew,L.G.,comps.Sustainingaspeninwesternlandscapes:symposium
proceedings.Gen.Tech.Rep.RMRS‐P‐18.FortCollins,CO:U.S.DepartmentofAgriculture,USFS,RockyMountainResearch
Station.460p.
Howard,J.L.1996.Populustremuloides.In:FireEffectsInformationSystem,[Online].U.S.DepartmentofAgriculture,
ForestService,RockyMountainResearchStation,FireSciencesLaboratory(Producer).Available:
http://www.fs.fed.us/database/feis
Johnston,B.C.2001.MultipleFactorsAffectAspenRegenerationontheUncompahgrePlateau,West‐CentralColorado.
Pages395‐414.In:Shepperd,W.D.,D.Binkley,D.L.Bartos,T.J.Stohlgren,andL.G.Eskew,compilers.Sustainingaspenin
westernlandscapes:symposiumproceedings.USDAForestServiceProceedingsRMRS‐P‐18.GrandJunction,CO.460p.
Kay,C.E.1993.AspenseedlingsinrecentlyburnedareasofGrandTetonandYellowstoneNationalParks.Northwest
Science.67(2):94‐104.
Kaye,M.W.2011.MesoscalesynchronyinquakingaspenestablishmentacrosstheinteriorwesternUS.ForestEcology
andManagement262:389‐397.
Knight,D.H.1994.Mountainsandplains:EcologyofWyominglandscapes.YaleUniversityPress,NewHaven,MA.338pp.
Kulakowski,D.,M.W.Kaye,andD.M.Kashian.2013.Long‐termaspencoverchangeinthewesternUS.ForestEcologyand
Management299:52‐59.
Kulakowski,D.,C.Matthews,D.Jarvis,andT.T.Veblen.2013.Compoundeddisturbancesinsub‐alpineforestsinwestern
Coloradofavorfuturedominancebyquakingaspen(Populustremuloides).JournalofVegetationScience24:168‐176.
Little,E.L.,Jr.1971.AtlasoftheUnitedStatestrees.Volume1.Conifersandimportanthardwoods.Misc.Publ.1146.
Washington,DCU.S.DepartmentofAgriculture,ForestService.320p.
Logan,J.2008.GypsyMothRiskAssessmentintheFaceofaChangingEnvironment:ACaseHistoryApplicationinUtah
andtheGreaterYellowstoneEcosystem.RestoringtheWest2008:FrontiersinAspenRestoration,UtahStateUniversity,
Logan,Utah.
Morelli,T.L.andS.C.Carr.2011.Areviewofthepotentialeffectsofclimatechangeonquakingaspen(Populus
tremuloides)intheWesternUnitedStatesandanewtoolforsurveyingsuddenaspendecline.Gen.Tech.Rep.PSW‐GTR‐
235.Albany,CA:U.S.DepartmentofAgriculture,ForestService,PacificSouthwestResearchStation.31p.
Mueggler,W.F.1988.AspencommunitytypesoftheIntermountainRegion.USDAForestServiceGeneralTechnical
ReportINT‐250.IntermountainResearchStation,Ogden,Utah.135pp.
Perala,D.A.1990.PopulustremuloidesMichx.quakingaspen.Pp555‐569In:Burns,RussellM.;Honkala,BarbaraH.,
technicalcoordinators.SilvicsofNorthAmerica:Volume2,Hardwoods.AgricultureHandbook654.Washington,DC:U.S.
DepartmentofAgriculture,ForestService.Available:http://www.srs.fs.usda.gov/pubs/misc/ag_654_vol2.pdf
Rehfeldt,G.E.,D.E.Ferguson,andN.L.Crookston.2009.Aspen,climate,andsuddendeclineinwesternUSA.ForestEcology
andManagement258:2353–2364
Romme,W.H.,Turner,M.G.,Gardner,R.H.,Hargrove,W.W.,Tuskan,G.A.,Despain,D.G.,andRenkin,R.A.1997.ARare
EpisodeofSexualReproductioninAspen(PopulustremuloidesMichx.)Followingthe1988YellowstoneFires.Natural
AreasJournal.17:17‐25.
WorrallJ.J.,L.Egeland,T.Eager,R.Mask,E.Johnson,etal.2008.RapidmortalityofPopulustremuloidesinsouthwestern
Colorado,USA.ForestEcologyandManagement255(3‐4):686‐696.http://dx.doi.org/10.1016/j.foreco.2007.09.071.
ClimateChangeVulnerabilityAssessmentforColoradoBLM49
Worrall,J.J.,G.E.Rehfeldt,A.Hamann,E.H.Hogg,S.B.Marchetti,M.Michaelian,andL.K.Gray.2013.Recentdeclinesof
PopulustremuloidesinNorthAmericalinkedtoclimate.ForestEcologyandManagement229:35‐51.

50ColoradoNaturalHeritageProgram©2015
LODGEPOLE
Forestsdominatedbylodgepolepine
R.Rondeau
extentexaggeratedfordisplay
Climate Vulnerability Rank: Moderate
Vulnerability summary
Key Vulnerabilities:Warmeranddrierconditionsarelikelytoincreasetheimpactoffireandinsect
outbreaksinlodgepoleforests.Lodgepolestandsnearthesouthernendoftherangemaybelost.
Lodgepolepineforestisrankedmoderatelyvulnerabletothe
effectsofclimatechangebymid‐century.Primaryfactors
contributingtothisrankingareitsvulnerabilitytoforest
disturbancesthatmayincreaseinthefuture,andthefactthatitis
atthesouthernedgeofitsdistributioninColorado.Lodgepole
forestsinColoradohaveexperiencedsignificantmortalitydueto
themountainpinebeetle,andtheinteractionofthisfactorwith
increasedfireanddroughtfrequencyandintensitycouldleadto
conspicuouschangesinthefutureextentandformofthese
forests.
Distribution
ThismatrixformingsystemiswidespreadinuppermontanetosubalpineelevationsoftheRocky
Mountains,Intermountainregion,andnorthintotheCanadianRockies.Lodgepolepinereachesthe
southernextentofitsrangeataboutthemiddleoftheupperGunnisonBasin(Johnston1997),so
thisecosystemisnotfoundinsouthernColorado.
ClimateChangeVulnerabilityAssessmentforColoradoBLM51
Characteristic species
TheseforestsaredominatedbyRockyMountainlodgepolepine(Pinuscontortavar.latifolia)with
shrub,grass,orbarrenunderstories.Manystandsconsistofonlylodgepolepine,butothersare
intermingledwithmixedconiferorquakingaspenstands(thelatteroccurringwithinclusionsof
deeper,typicallyfine‐texturedsoils).Shrubandherbaceouslayersareoftenpoorlydevelopedin
lodgepolepineforests,andplantspeciesdiversityislow.Somecommonunderstoryshrubsinclude
kinnikinnick(Arctostaphylosuva‐ursi),snowbrushceanothus(Ceanothusvelutinus),twinflower
(Linnaeaborealis),creepingbarberry(Mahoniarepens),antelopebitterbrush(Purshiatridentata),
dwarfbilberry(Vacciniumcaespitosum),whortleberry(Vacciniummyrtillus),grousewhortleberry
(Vacciniumscoparium),andcurrant(Ribesspp.).
Environment
Soilssupportingtheseforestsaretypicallywell‐drained,gravelly,havecoarsetextures,areacidic,
andrarelyformedfromcalcareousparentmaterials.InColorado,lodgepolepineforestsgenerally
occurbetween8,000‐10,000feetongentletosteepslopesonallaspects.Somelodgepoleforests
persistonsitesthataretooextremeforotherconiferstoestablish.Theseincludeexcessivelywell‐
drainedpumicedeposits,glacialtillandalluviumonvalleyfloorswherethereiscoldair
accumulation,warmanddroughtyshallowsoilsoverfracturedquartzitebedrock,andshallow
moisture‐deficientsoilswithasignificantcomponentofvolcanicash.
Dynamics
Lodgepolepineisanaggressivelycolonizing,shade‐intolerantconifer.Establishmentisepisodic
andlinkedtostand‐replacingdisturbances,primarilyfire.ThefrequencyofnaturalfiresinRocky
Mountainlodgepolepinestandsrangesfromafewyearsto200ormoreyears(Davisetal.1980).
Lowtomoderateserveritysurfacefiresarelikelytohaveareturnintervalontheorderofafew
decades,whilestand‐replacingfiresaregenerallylessfrequent(Crane1982).
Lodgepolepinesproducebothopenandclosed,serotinouscones,andcanreproducequicklyaftera
fire.Followingstand‐replacingfires,lodgepolepinerapidlycolonizesanddevelopsintodense,
even‐agedstands(sometimesreferredtoas“doghair”stands).Thisfire‐adaptedspecieshasthe
potentialtomoveintoareaswherespruce‐firforestsburn.Theproductionofserotinousconesisa
highlyheritabletraitamongRockyMountainlodgepolepinepopulations(Parchmanetal.2012).
Serotinousconesappeartobestronglyfavoredbyfire,andallowrapidcolonizationoffire‐cleared
substrates(BurnsandHonkala1990),butserotinyisalsoselectedagainstbycontinuousremoval
ofthecanopyseed‐bankbyactiveseedpredators(BenkmanandSiepielski2004).Treeswith
serotinousconesarefavoredunderconditionsofhighfirefrequencyandlowpredation,but
nonserotinyhasanadvantageunderveryhighseedpredation,regardlessoffirefrequency(Talluto
andBenkman2014).
52ColoradoNaturalHeritageProgram©2015
CCVA Scoring
Exposure‐Sensitivity (Potential Impact) Rank
PercentColoradoacreswithprojectedtemp>max&pptdelta<5%0%
InitialExposure‐SensitivityRankLow
PercentColoradoacreswithtemp<=max&pptdelta<5%morethan50%?No(7.3%)
FinalExposure‐SensitivityRankLow
Exposuretotemperaturechange
Underprojectedmid‐centurytemperatures,lessthan1%ofthecurrentrangeoflodgepolepine
forestinColoradowouldexperienceannualmeantemperaturesabovethecurrentstatewide
maximum.
Exposuretoprecipitationchange
About7%oflodgepoleforestecosysteminColoradowillbeexposedtoeffectivelydrierconditions
evenunderunchangedorslightlyincreasedprecipitationprojectedformid‐century.
Sensitivityofecosystemtotemperatureandprecipitation
Lodgepolepineistolerantofverylowwintertemperatures,andinmanylodgepoleforestssummer
temperaturescanfallbelowfreezing,sothereisnotruefrost‐freeseason(LotanandPerry1983).
Lodgepolepineisalsoabletotakeadvantageofwarmgrowingseasontemperatures,andalonger
growingseasonduetowarmerfalltemperaturescouldfavorthegrowthoflodgepolepine(Villalba
etal.1994,Chhinetal.2008).InsouthernColorado,whitefir(Abiesconcolor)appearstotakethe
placeoflodgepolepineinconiferousforestsofsimilarelevations.Whitefirappearstotolerate
warmertemperaturesthanlodgepolepine(Thompsonetal.2000);underwarmerconditionsit
maybeabletomoveintoareascurrentlyoccupiedbylodgepoleforest.
Lodgepolepineisanorthernspeciesthatdoesexceptionallywellinverycoldclimatesandcan
tolerateawiderangeofannualprecipitationpatterns,fromfairlydrytofairlywet,butgenerally
growsonlywhereannualprecipitationisatleast18‐20inches(Mason1915,LotanandPerry
1983).Lodgepolepineforestsarefoundondriersitesthanspruce‐firforest,althoughsnowfallis
typicallyheavyintheseforests.Summersareoftenquitedry,andlodgepolepineisdependenton
snowmeltmoistureformostofthegrowingseason.Inlowsnowpackyears,growthisreduced(Hu
etal.2010).
Resilience and Adaptive Capacity Rank
OverallScore: 0.35Rank: Low
Bioclimaticenvelopeandrange
Averagedcategoryscore:0.50
ClimateChangeVulnerabilityAssessmentforColoradoBLM53
LodgepolepinesubspeciesarewidelydistributedinNorthAmerica,butRockyMountainlodgepole
reachesthesouthernedgeofitsdistributioninsouth‐centralColorado.Lodgepoleforestsarenot
foundatthehighestelevations,butrangefrommontanetosubalpine.Statewide,theannual
averageprecipitationrangeforlodgepoleforestcoversabout64%ofColorado’soverall
precipitationrange.Growingseasonlengthforlodgepolebroadlyoverlapsthatofthewarmerend
ofthespruce‐firdistribution,andcoversabout35%ofthestatewiderangeofgrowingdegreedays.
Growthformandintrinsicdispersalrate
Score:0
Thetreegrowthformandslowdispersalrateoflodgepolepinegivethisecosystemalowresilience
scoreinthiscategory.
Vulnerabilitytoincreasedattackbybiologicalstressors
Score:0
Althoughinvasivespeciesaregenerallynotathreat,lodgepoleforestsarevulnerabletothepest
outbreaksthatappeartoincreasewithwarmer,drier,drought‐proneclimates.Biologicalstressors
thatinteractwithfiredynamicsoflodgepoleforestincludeinfestationsoflodgepolepinedwarf‐
mistletoeandmountainpinebeetle(Anderson2003).Dwarfmistletoereducestreegrowthand
coneproduction,andgenerallyleadstoearliermortality(HawksworthandJohnson1989).
AlthoughlodgepoleforestsarestillcommonacrossColorado,mosthaveexperiencedwidespread
damagefromasevereoutbreakofmountainpinebeetle.Thepinebeetleisanativespecies,and
periodicoutbreaksofthisinsectarepartofthenaturalcyclethatmaintainsColorado’smountain
forests.LodgepoleforestsareexpectedtopersistinColorado(Kaufmannetal.2008),although
foreststructuremaydifferfromwhathasbeenpresenthistorically.
Vulnerabilitytoincreasedfrequencyorintensityofextremeevents
Score:0.5
Warmingtemperaturesandeffectivelydrierconditionsareexpectedtohaveaneffectonfire
frequencyandseverity.Firesuppressioneffectsinlodgepolepineforestsareevidentatalandscape
levelinanoveralllackofvarietyinsuccessionalstages.Individuallodgepolestandsmaynotbe
outsidethenaturalrangeofvariation,butatalandscapelevelfiresuppressionhasprobablyledto
larger,denser,morehomogenouspatchesthataremorefavorableforlargefireandheavy
infestationsofmountainpinebeetle(Keaneetal.2002).Thecurrentoutbreakofmountainpine
beetleappearstobesubsiding,leavingthepotentialforlargefireswithextremebehaviortooccur
inthekilledforests(Kaufmannetal.2008).
Otherindirecteffectsofnon‐climatestressors–landscapecondition
Score:0.75
LodgepoleforestlandscapesinColoradoaregenerallyingoodcondition.Althoughlarge,intact
patchesoflodgepoleforestpersistinColorado,thismaychangeastheeffectsofextensivemountain
pinebeetlemortalityandincreasedfireextentandfrequencyreshapethelodgepolematrix.
54ColoradoNaturalHeritageProgram©2015
Developmentofexurbanorrecreationalareasisaminorsourcesofdisturbanceandfragmentation
inlodgepoleforests,asaretheassociatedroadsandutilitycorridors.TimberharvestinColorado’s
lodgepoleforestshasdeclinedsignificantlysincethelate19thcentury,butarecentincreaseinthe
useofbeetle‐killwoodhadmaintainedasmallmarketforthisspecies.Woodharvestactivitiesarea
minorsourceofdisturbanceinthishabitattype,butextensivesalvageloggingandthinningmay
havelocallysevereimpacts.
Literature Cited
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Agriculture,ForestService,RockyMountainResearchStation,FireSciencesLaboratory(Producer).Available:
http://www.fs.fed.us/database/feis/
Benkman,C.W.andA.M.Siepielski.2004.Akeystoneselectiveagent?Pinesquirrelsandthefrequencyofserotinyin
lodgepolepine.Ecology85:2082‐2087.
Burns,R.M.,andB.H.Honkala,technicalcoordinators.1990a.SilvicsofNorthAmerica:Volume1.Conifers.USDAForest
Service.AgricultureHandbook654.Washington,DC.675pp.
Chhin,S.,E.H.Hogg,V.J.Lieffers,andS.Huang.2008.Influencesofclimateontheradialgrowthoflodgepolepinein
Alberta.Botany86:167‐178.
Crane,M.F.1982.FireecologyofRockyMountainRegionforesthabitattypes.USDAForestServicefinalreport.272pp.
Davis,KathleenM.;Clayton,BruceD.;Fischer,WilliamC.1980.FireecologyofLoloNationalForesthabitattypes.INT‐79.
Ogden,UT:U.S.DepartmentofAgriculture,ForestService,IntermountainForestandRangeExperimentStation.77p.
Hawksworth,F.G.andD.W.Johnson.1989.BiologyandmanagementofdwarfmistletoeinlodgepolepineintheRocky
Mountains.Gen.Tech.Rep.RM‐169.FortCollins,CO:U.S.DepartmentofAgriculture,ForestService,RockyMountain
ForestandRangeExperimentStation.38p.
Hu,J.,D.J.P.Moore,S.P.Burns,andR.K.Monson.2010.Longergrowingseasonsleadtolesscarbonsequestrationbya
subalpineforest.GlobalChangeBiology16:771‐783.
JohnstonB.C.1997.EcologicaltypesoftheUpperGunnisonBasin.Reviewdraft.USDA,ForestService,Gunnison,CO.539
pp.
KaufmannM.R.,G.H.Aplet,M.Babler,W.L.Baker,B.Bentz,M.Harrington,B.C.Hawkes,L.StrohHuckaby,M.J.Jenkins,D.M.
Kashian,R.E.Keane,D.Kulakowski,C.McHugh,J.Negron,J.Popp,W.H.Romme,T.Schoennagel,W.Shepperd,F.W.Smith,
E.KennedySutherland,D.Tinker,andT.T.Veblen.2008.Thestatusofourscientificunderstandingoflodgepolepineand
mountainpinebeetles–afocusonforestecologyandfirebehavior.TheNatureConservancy,Arlington,VA.GFItechnical
report2008‐2.
Lotan,J.E.andD.A.Perry.1983.Ecologyandregenerationoflodgepolepine.Agric.Handb.606.Washington,DC:U.S.
DepartmentofAgriculture,ForestService.51p.
Mason,D.T.1915.LifehistoryoflodgepolepineintheRockyMountains.Bulletin154.Washington,DC:U.S.Departmentof
Agriculture,ForestService.35p.
ParchmanT.L.,Z.Gompert,J.Mudge,F.D.Schilkey,C.W.Benkman,andC.A.Buerkle.2012.Genome‐wideassociation
geneticsofanadaptivetraitinlodgepolepine.MolecularEcology21:2991–3005.
ClimateChangeVulnerabilityAssessmentforColoradoBLM55
Talluto,M.V.andC.W.Benkman.2014.Conflictingselectionfromfireandseedpredationdrivesfine‐scaledphenotypic
variationinawidespreadNorthAmericanconifer.PNAS111:9543‐9548.
Thompson,R.S.,K.H.Anderson,andP.J.Bartlein.2000.Atlasofrelationsbetweenclimaticparametersanddistributions
ofimportanttreesandshrubsinNorthAmerica.U.S.GeologicalSurveyProfessionalPaper1650‐A.
Villalba,R.,T.T.Veblen,andJ.Ogden.1994.ClimaticinfluencesonthegrowthofsubalpinetreesintheColoradoFront
Range.Ecology75:1450‐1462.
Wheeler,N.C.andW.B.Critchfield.1985.Thedistributionandbotanicalcharacteristicsoflodgepolepine:biogeographical
andmanagementimplications.In:Baumgartner,D.M.,R.G.Krebill,J.T.Arnott,andG.F.Weetman,compilersandeditors.
Lodgepolepine:Thespeciesanditsmanagement:Symposiumproceedings;1984May8‐10;Spokane,WA;1984May14‐
16;Vancouver,BC.Pullman,WA:WashingtonStateUniversity,CooperativeExtension:1‐13.

56ColoradoNaturalHeritageProgram©2015
MIXED CONIFER
Dry‐mesicandmesicforestsorwoodlandsofDouglasfir,whitefir,otherconiferspecies,and
occasionalaspenstands
R.Rondeau
extentexaggeratedfordisplay
Climate Vulnerability Rank: Moderate
Vulnerability summary
Key Vulnerabilities:Warmeranddrierconditionscanbeexpectedtochangetherelativetreespecies
abundanceinmixedconiferforests.Althoughsomestandsmayconverttoothertypes,thediverse
speciescompositionoftheseforestsincreasesthelikelihoodthatsomespecieswillbenefitunderfuture
conditions.Novelmixedconifertypesmayappear.
Theecotonalnatureofmixedconiferstandsincreasesthe
difficultyofinterpretingtheirvulnerabilitytoclimatechange,and
theircapacitytomoveintonewareas.Thediversityofspecies
withinmixedconiferforestmayincreaseitsflexibilityintheface
ofclimatechange.Changingclimateconditionsarelikelytoalter
therelativedominanceofoverstoryspecies,overallspecies
compositionandrelativecover,primarilythroughtheactionof
fire,insectoutbreak,anddrought.Droughtanddisturbance
tolerantspecieswillbefavoredoverdroughtvulnerablespecies.
Speciessuchasbluesprucethatareinfrequentandhavea
narrowbioclimaticenvelopearelikelytodeclineormoveupin
elevation.AbundantspeciesthathaveawidebioclimaticenvelopesuchasGambeloakandaspen
arelikelytoincrease.Outcomesforparticularstandswilldependoncurrentcompositionand
location.Currentstandsofwarm,drymixedconiferbelow8,500ftmaybeathigherriskormay
converttopureponderosapinestandsasfutureprecipitationscenariosfavorrainratherthan
snow.Upwardmigrationintonewareasmaybepossible.
ClimateChangeVulnerabilityAssessmentforColoradoBLM57
Distribution
InColoradothesemixed‐coniferforestsoccuronallaspectsatelevationsrangingfrom4,000to
10,800ft(1,200‐3,300m).Thecompositionandstructureofoverstoryisdependentuponthe
temperatureandmoisturerelationshipsofthesite,andthesuccessionalstatusoftheoccurrence.
Thesecomplexforestandwoodlandcommunitiesareoftenintermingledwithotherforesttypes,
includingponderosapine,aspen,lodgepole,andspruce‐fir,dependingonelevation,andmaybe
adjacenttoshrublandandripariantypesaswell.
Thesimilarenvironmentaltolerancesofmixed‐coniferandaspenforestmeansthatthetwoforest
typesaresomewhatintermixedinmanyareas.Theseforestsappeartorepresentabiophysical
spacewhereanumberofdifferentoverstoryspeciescanbecomeestablishedandgrowtogether.
Localconditions,biogeographichistory,andcompetitiveinteractionsovermanydecadesareprime
determinantsofstandcomposition.
Characteristic species
Severalsub‐typesorphases,representingacontinuumfromwarm‐drytocold‐wethavebeen
describedfortheseforests(Rommeetal.2009),andspeciescomposition,standstructure,andsite
characteristicsvaryaccordingly.
Thesemixed‐speciesforestsmayincludeDouglas‐fir(Pseudotsugamenziesii),whitefir(Abies
concolor),ponderosapine(Pinusponderosa),quakingaspen(Populustremuloides),bluespruce
(Piceapungens),Engelmannspruce(Piceaengelmannii),subalpinefir(Abieslasiocarpa),andlimber
pine(Pinusflexilis),whichreachesthesouthernlimitofitsdistributionintheSanJuanmountains.
Warm‐drysitesarecharacterizedbyDouglas‐fir,oftenwithponderosapineandGambeloak
(Quercusgambelii).Cool‐moiststandsarelikelytobedominatedbyDouglasfir,whitefir,blue
spruceandsomequakingaspen.TypicalunderstoryshrubspeciesincludeRockyMountainmaple
(Acerglabrum),Saskatoonserviceberry(Amelanchieralnifolia),kinnikinnick(Arctostaphylosuva‐
ursi),rockspirea(Holodiscusdumosus),fivepetalcliffbush(Jamesiaamericana),commonjuniper
(Juniperuscommunis),creepingbarberry(Mahoniarepens),Oregonboxleaf(Paxistimamyrsinites),
mountainninebark(Physocarpusmonogynus),mountainsnowberry(Symphoricarposoreophilus),
thimbleberry(Rubusparviflorus),andwhortleberry(Vacciniummyrtillus).Wheresoilmoistureis
favorable,theherbaceouslayermaybequitediverse.
CharacteristicanimalspeciesinmixedconiferforestincludeRuby‐crownedkinglet,Hermitthrush,
Hammond’sflycatcher,Williamson’ssapsucker,Yellow‐rumpedwarbler,Pinesiskin,Red‐breasted
nuthatch,Townsend’ssolitaire,Westerntanager,Browncreeper,Cassin’sfinch,Redcrossbill,Olive‐
sidedflycatcher,Mountainchickadee,Junco,Snowshoehare,Lynx,andPinemarten.
Environment
Thecompositionandstructureofoverstoryisdependentuponthetemperatureandmoisture
relationshipsofthesite,andthesuccessionalstatusoftheoccurrence(DeVeliceetal.1986,
Muldavinetal.1996).Driersites,oftenonsoutherlyaspects,maybesimilartoponderosapine
forest,butwithDouglas‐firandwhitefirasimportantcanopycomponents.Historically,these
standsweresubjecttofairlyfrequentlowtomoderateintensityfire,whichhelpedtomaintaina
58ColoradoNaturalHeritageProgram©2015
relativelyopenstructure(Rommeetal.2009).Moremesicstandsarefoundincoolravinesandon
north‐facingslopes,lackponderosapine,andarelikelytobedominatedbyDouglas‐firandwhite
firwithbluespruceorquakingaspenstands,andoccasionalinclusionsofEngelmannspruceor
subalpinefir.Thesecool‐moiststandswouldhavelessfrequentfires,andsoilmoistureconditions
thatallowthegrowthofdensestandsthateventuallyburninahigh‐intensityfire(Rommeetal.
2009).
Soilsofthisecosystemarevariable,andmaybederivedfromparentmaterialsofigneous,
metamorphic,orsedimentaryorigin.Moreopenwoodlandcommunitiesaretypicallyfoundonsoils
thatareshallow,rocky,andwell‐drained.
Dynamics
Long‐termecologicaldynamicsofmixedconiferforestsarerelativelyunderstudied(Rommeetal.
2009).Therehasbeenconsiderablerecentdebateabouthistoricrangeofvariationforstand
densityandhigh‐severityfireincidenceinmixedconiferforests(WilliamsandBaker2012,Fuleet
al.2013,WilliamsandBaker2014).Naturalfireprocessesinthissystemareprobablyhighly
variableinbothreturnintervalandseverity,dependingonstandcomposition,siteconditions,
biogeographichistory,andshort‐andlong‐termclimatepatterns.Forinstance,droughtandhigh
temperaturespriortofireinitiationareassociatedwithlargerburnedareaasfinefuelsbecomedry
(Littelletal.2009).
Althoughcoolmoistmixed‐coniferforestsaregenerallywarmeranddrierthanspruce‐firforests,
thesestandsareofteninrelativelycool‐moistenvironmentswherefireswerehistorically
infrequentwithmixedseverity.Whenstandsareseverelyburned,aspenoftenresprouts.Warm‐
drymixedconiferforestshadahistoricfire‐regimethatwasmorefrequent,withmixedseverity.In
areaswithhighseverityburns,aspenorGambeloakoftenresproutsanddominatesthesitefora
relativelylongperiodoftime.Insomelocations,muchoftheseforestshavebeenloggedorburned
duringEuropeansettlement,andpresent‐dayoccurrencesaresecond‐growthforestsdatingfrom
fire,logging,orotheroccurrence‐replacingdisturbances(MaukandHenderson1984,Chappellet
al.1997).
Additionaldisturbancesinmixedconiferforestsmaybeduetowindstormsorinsect‐pathogen
outbreaks.Sprucebudworminfestationsareamajorsourceoftreemortalityandcanaffect
landscape‐scaledynamicsinmixedconiferforest(Rommeetal.2009).
CCVA Scoring
Exposure‐Sensitivity (Potential Impact) Rank
PercentColoradoacreswithprojectedtemp>max&pptdelta<5%0.1%
InitialExposure‐SensitivityRankLow
PercentColoradoacreswithtemp<=max&pptdelta<5%morethan50%?Yes(61.0%)
FinalExposure‐SensitivityRankModerate
ClimateChangeVulnerabilityAssessmentforColoradoBLM59
Exposuretotemperaturechange
Underprojectedmid‐centurytemperatures,lessthan1%ofthecurrentrangeofmixedconifer
forestinColoradowouldexperienceannualmeantemperaturesabovethecurrentstatewide
maximum.
Exposuretoprecipitationchange
About61%ofmixedconiferforestecosysteminColoradowillbeexposedtoeffectivelydrier
conditionsevenunderunchangedorslightlyincreasedprecipitationprojectedformid‐century.
Sensitivityofecosystemtotemperatureandprecipitation
Withthevariationfromwarm‐drytypestocool‐moisttypes,mixedconiferforestshaveabroad
ecologicalamplitude,andvariationbetweenstandsisobviouslyinfluencedbybothtemperature
andprecipitation.Theeffectsofclimaticfactorsontheecosystemasawhole,however,arelittle
known,especiallyinColorado.GenerallywarmingconditionsduringtheearlyHoloceneallowedfor
theexpansionofsomemixedconiferforesttreespeciesincludingDouglas‐fir,ponderosapine,and
Gambeloak,andthedevelopmentofmixedconiferforestsinareaspreviouslycharacterizedby
subalpinespecies(Andersonetal.2008).
StudiesfromthesouthwesternUSindicatethatfactorscontrollingthedistributionandpersistence
ofthecomponenttreespeciesinmixedconiferforestsarecomplexandnoteasilyexplainedata
broadclimaticlevel.Forinstance,KaneandKolb(2014)foundthatalthoughdroughtwasan
importantdriverforaspenmortalityinmixedconifer,therewasnosimilareffectforthemuch
slower‐growinglimberpine.Douglas‐firandwhitefirmortalityduringthedroughtwasmoderately
associatedwithpreviousgrowthrate(i.e.,sitequality),indicatingthatlonger‐termprocessessuch
ascompetitionanddisturbancehistorymayalsoplayarole.Cool‐moistmixedconiferforestsof
higherelevationsmaybelesssusceptibletodrought(AdamsandKolb2005),butarenot
completelyprotectedbygenerallycooler,wetterconditions(Kaneetal.2014).
Resilience and Adaptive Capacity Rank
OverallScore: 0.60Rank: Moderate
Bioclimaticenvelopeandrange
Averagedcategoryscore:0.78
Mixedconiferforestsoccuratfoothillandmontaneelevationsthroughoutcentralandwestern
Colorado,andhaveafairlywideecologicalamplitude.Theseforestshavesignificantpresencein
60%ofColorado’soverallprecipitationrange,andin51%ofthestate’sgrowingdegreedaysrange.
Thehighlyvariableandecotonalnatureofmixedconiferforestscontributestothehigherresilience
scoreinthiscategory.
Growthformandintrinsicdispersalrate
Score:0
60ColoradoNaturalHeritageProgram©2015
Thetreegrowthformandslowdispersalrateofthedominantconiferspeciesgivethisecosystema
lowresiliencescoreinthiscategory.
Vulnerabilitytoincreasedattackbybiologicalstressors
Score:0.7
StandsinthesouthernpartofColoradohavebeenimpactedbythewesternsprucebudwormand
drought.Budwormoutbreaksarepartofanaturalcycleinmixedconiferforest,butmaybe
intensifiedbyincreasingdroughtfrequencyandthegenerallyhighertemperaturesprojectedin
comingdecades.
Vulnerabilitytoincreasedfrequencyorintensityofextremeevents
Score:0.7
Inareasadjacenttodevelopment,mixedconiferstandsmaybepartofthewildland‐urbaninterface,
wheretheyaremostlikelytobethreatenedbytheeffectsoffiresuppression.Theabsenceofa
naturalfireregimeintheseforestshasresultedinincreasedtreedensityandthebuildupofduff
andlitter,whichmayincreasetheseverityoffirewhenitdoesoccur.Asyear‐roundtemperatures
increaseandprecipitationshiftsmoretowardraininsteadofsnow,conditionsfavorablefor
increasingareaburnedmaydevelop(Littelletal.2009).However,manymixedconiferstandsin
Coloradoarenotasseverelyimpactedbyfiresuppression.
Otherindirecteffectsofnon‐climatestressors–landscapecondition
Score:0.81
MixedconiferforestlandscapesinColoradoaregenerallyinverygoodcondition.Exurban
developmentandrecreationalareadevelopmentareathreattotheseforestsalongtheFrontRange
andI‐70corridorinmountainareas.Roadsandutilitycorridorsareasourceofdisturbanceand
fragmentationinmixedconiferforeststatewide,butthesestandsnaturallyoccurinsmallerpatches
thansomeotherforesttypes,sothreatsareminor.Anumberoftreespeciesinmixedconiferare
suitablefortimberharvest,sologgingisanongoingsourceofdisturbanceintheseforests.Threats
fromlivestockgrazingandhuntingorrecreationalactivitiesareminimalformixedconiferforests.
Miningandminetailingsareasmallsourceofdisturbance.
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Romme,W.H.,Floyd,M.L.,Hanna,D.,2009.Historicalrangeofvariabilityandcurrentlandscapeconditionanalysis:South
CentralHighlandssection,SouthwesternColoradoandNorthwesternNewMexico.Col.For.Rest.Inst.,FortCollins,CO.
Steele,R.,R.D.Pfister,R.A.Ryker,andJ.A.Kittams.1981.ForesthabitattypesofcentralIdaho.USDAForestService
GeneralTechnicalReportINT‐114.IntermountainForestandRangeExperimentStation,Ogden,UT.138pp.

62ColoradoNaturalHeritageProgram©2015
PINYON‐JUNIPER
Woodlandsandshrublandsdominatedbypinyonpineandjuniperspecies
S.Kettler
extentexaggeratedfordisplay
Climate Vulnerability Rank: High
Vulnerability summary
Key Vulnerabilities:Hotanddryconditionsarelikelytoincreasetheimpactoffireandinsectoutbreaks,
andfavorjuniperoverpinyonpine.Substratesplayakeyroleindeterminingsoilmoistureavailability
forindividualstands.
Variabledisturbanceandsiteconditionsacrossthedistribution
ofthisecosystemhaveresultedinadynamicmosaicof
interconnectedcommunitiesandsuccessionalstagesacrossthe
landscape.Sincethelastmajorglacialperiod,thedistribution
andrelativeabundanceofpinyonandjuniperhasfluctuatedwith
changingclimaticconditions.Warmingconditionsduringthe
pasttwocenturies,togetherwithchangingfireregime,livestock
grazing,andatmosphericpollutionincreasedtheabilityofthis
ecosystemtoexpandintosomeneighboringcommunities,at
bothhigherandlowerelevations.However,precipitationand
temperaturepatternsareprojectedtochangeinadirectionthat
islessfavorableforpinyon,sothatjunipermaybecomemoredominant,andthesehabitatsare
unabletopersistorexpandintheircurrentform.Primaryfactorscontributingtothehighranking
arethevulnerabilityofthesewoodlandstotheinteractionofdrought,fire,andinsect‐caused
mortality,whichislikelytoincreaseunderchangingclimate,andtheextenttowhichthecurrent
landscapeconditionofthehabitathasbeenimpactedbyanthropogenicdisturbance.
ClimateChangeVulnerabilityAssessmentforColoradoBLM63
Distribution
TheNorthAmericandistributionofthisecosystemiscenteredintheColoradoPlateau,generally
southwestofColorado.Pinyon‐juniperformsthecharacteristicwoodlandofColorado’swestern
mesasandvalleys,whereitistypicallyfoundatlowerelevations(rangingfrom4,900‐8,000ft)on
drymountainsandfoothills.Pinyonandjunipermayformsparseshrublandsorwoodlandson
rockytablelandswherevegetationislargelyconfinedtosmallsoilpocketsinexposedbedrock.
Pinyon‐juniperwoodlandsalsooccurondrymountainsandfoothillsinsouth‐centralandsouth‐
easternColorado,inmountainsandplateausofnorthernNewMexicoandArizona,andextendout
ontoshalebreaksintheGreatPlains.Inthecanyonsandtablelandstothesoutheast,pinyonis
absent,andjuniperaloneformswoodlandsandsavannas.Standsareoftenadjacenttoand
intermingledwithoak,sagebrush,orsaltbushshrubland.
Characteristic species
Pinyonpine(Pinusedulis)andjuniperformthecanopy.Inwesternpinyon‐juniperwoodlandsof
lowerelevations,Utahjuniper(Juniperusosteosperma)isprevalentandRockyMountainjuniper(J.
scopulorum)maycodominateorreplaceitathigherelevations.Insoutheasternpinyon‐juniper
woodlandsone‐seedjuniper(Juniperusmonosperma) replacesUtahjuniper.Theunderstoryis
highlyvariable,andmaybeshrubby,grassy,sparselyvegetated,orrocky.Comeretal.(2003)
separateColorado’spinyon‐juniperintofourecologicalsystems:ColoradoPlateauPinyon‐Juniper
Woodland,ColoradoPlateauPinyon‐JuniperShrubland,ColoradoPlateauMixedBedrockCanyon
andTableland,andSouthernRockyMountainPinyon‐JuniperWoodland.
Pinyon‐juniperwoodlandassociationsarecharacterizedbystandswith25‐60%canopycoverof
treesthataretypically10‐30ft(3‐10m)inheight.Ondryrockymesatopsandslopesthesecanopy
dominantsmaybedwarfed(<3mtall),formingtallshrublands.Onsteepclifffaces,narrow
canyons,andopentablelandsofpredominantlysedimentarysandstone,shale,andlimestone,
pinyonandjunipermayformverysparseshrublandsincracksandpocketswheresoilhas
accumulated.Pinyon‐juniperstandsmaybesolelydominatedbypinyonpine,ormaybeco‐
dominatedbyjuniperspecies.Dependingonsubstrate,theunderstorycanrangefromarelatively
richmixtureofevergreenand/ordeciduousshrubs,toasparsetomoderatelydenseherbaceous
layerdominatedbyperennialgrasses(withorwithoutshrubs),tonovegetationatall(Reidetal.
1999).
Characteristicshrubsanddwarf‐shrubsincludeblacksagebrush(Artemisianova),bigsagebrush
(Artemisiatridentata),Utahserviceberry(Amelanchierutahensis),littleleafmountainmahogany
(Cercocarpusintricatus),mountainmahogany(Cercocarpusmontanus),yellowrabbitbrush
(Chrysothamnusviscidiflorus),mormon‐tea(Ephedraviridis),broomsnakeweed(Gutierrezia
sarothrae),Stansburycliffrose(Purshiastansburiana),antelopebitterbrush(Purshiatridentata),
Gambeloak(Quercusgambelii),andmountainsnowberry(Symphoricarposoreophilus).
Perennialgraminoidsarethemostabundantspeciesinthesparsetomoderatelydenseherbaceous
layer.CharacteristicspeciesincludeIndianricegrass(Achnatherumhymenoides),sideoatsgrama
(Boutelouacurtipendula),bluegrama(Boutelouagracilis),threeawn(Aristidaspp.),Arizonafescue
(Festucaarizonica),needle‐and‐thread(Hesperostipacomata),bluebunchwheatgrass
64ColoradoNaturalHeritageProgram©2015
(Pseudoroegneriaspicata),muttongrass(Poafendleriana),James'galleta(Pleuraphisjamesii),and
westernwheatgrass(Pascopyrumsmithii).Theforblayermaybediverse(andmayincludea
numberofrarespecies),butcontributeslittlecover.
Pinyonjay,Plumbeousvireo,Junipertitmouse,Grayflycatcher,Black‐throatedgraywarbler,and
Bushtitaregoodindicatorsfortheecosystem.
Environment
Dependingonsubstrate,pinyon‐juniperstandsarevariableinstructureandcomposition.Stands
occuronavarietyofaspectsandslopes.Slopemayrangefromnearlyleveltosteep(upto80%).
Soilsvaryintexturerangingfromstony,cobbly,gravellysandyloamstoclayloamorclay.Parent
materialslikewisevarywidelyfromgranite,basalt,limestone,andsandstonetomixedalluvium
(Springfield1976).Soildepthsmayrangefromshallowtodeep.
Mesicareasaregenerallypinyon‐dominated,whilejunipersareabletodominateondriersites
(Gottfried1992).Standsvaryconsiderablyinappearanceandcomposition,bothaltitudinallyand
geographically.Junipertendstobemoreabundantatthelowerelevations,pinyontendstobemore
abundantatthehigherelevations,andthetwospeciessharedominancewithinabroadmiddle‐
elevationzone(WoodinandLindsey1954,Heiletal.1993).Standsmayrangefromeven‐agedto
uneven‐agedstands.
Dynamics
Pinyon‐juniperwoodlandsareinfluencedbyclimate,fires,insect‐pathogenoutbreaks,andlivestock
grazing(West1999,Eager1999).Althoughitisclearthatthestructureandconditionofmany
pinyon‐juniperwoodlandshasbeensignificantlyalteredsinceEuropeansettlement(Tausch1999),
inrecentyearstherehasbeenanemergingrecognitionthatnotallofthesewoodlandsare
dramaticallychangedbyanthropogenicinfluence.Increasingdensityofpinyonjuniperwoodlands
andexpansionintoadjacentgrasslandorshrublandarewelldocumentedinsomeareas,butisnota
universalphenomenoninthewesternU.S.(Rommeetal.2009).Furthermore,thetree‐dominated
landscapecharacteristicofpinyon‐juniperwoodlandtodayisnotnecessarilyrepresentativeofthe
typicallandscapeofthepastfewmillennia(Tausch1999).Rommeetal.(2009)distinguishthree
pinyon‐junipertypes(persistentwoodlands,savannas,andwoodedshrublands),using
characteristicsofbasedcanopystructure,understory,anddisturbancehistory.Localsiteconditions
mayresultinafine‐scalemixtureoftypewithinalargermatrixofonetype.Thedifferences
betweenthesetypeshaveimportantimplicationsformanagementactions,andeffortstomaintain
orrestorenaturalprocessesinpinyon‐juniperhabitats.
Bothpinyonpineandjuniperarefairlyslowgrowing,andcanliveforhundredsofyears,alifecycle
thatiswelladaptedtoxerichabitats,butislesssuitableforquicklychangingconditions.Although
individualsofbothspeciesbecomereproductiveafterafewdecades,mostseedproductionisdue
tomaturetreesof75yearsofageorolder(Gottfried1992).Bothspeciesreproduceonlyfrom
seeds,anddonotresproutafterfire.Coneproductionofmaturepinyonpinetakesthreegrowing
seasons,andthelargeseedshaveafairlyshortlifespanof1‐2years(Ronco1990).Junipercones
(oftencalledberries)mayrequire1‐2yearsofripeningbeforetheycangerminate(Gottfried1992).
ClimateChangeVulnerabilityAssessmentforColoradoBLM65
Thesmallerseedsofjuniperaregenerallylong‐lived,survivingaslongas45years.Birdsare
importantdispersersofbothpinyonpineandjuniperseed(Gottfried1992).
Theeffectsoffireinalltypesofpinyon‐juniperdependinpartonfuelprovidedbybothcanopyand
understory,andbyweatherconditionsduringafire(Rommeetal.2009).Sparsewoodlandswith
littleunderstoryvegetationwouldtypicallyhavelimitedfirespreadandlittletreemortality.Astree
densityorunderstorycover(especiallyshrubs)increasesfirespreadisfacilitated,andtree
mortalitybecomesmorelikely.Rommeetal.(2009)concludedthatspreading,low‐intensity
surfacefireshavehistoricallyhadalimitedroleinthisecosystem,andthatinsteadthedominant
fireeffectismortalityofmosttreesandtop‐killofmostshrubswithintheburnedarea,regardless
oftreeorshrubsize.AtMesaVerdeNationalPark,wherepinyon‐juniperwoodlandshaveburnedin
fivelargefiressince1930,treeshavenotyetre‐established.Itisnotknownwhytreeshavenot
beensuccessfulintheseareas,whicharenowoccupiedbyshrubland(Floydetal.2000).
Formanypinyon‐juniperwoodlands,climatefluctuationandinsectordiseaseoutbreakaremore
importantinshapingstandstructurethanfire.Insectanddiseasemortalityisanaturalongoing
process,usuallyatalowlevel,butoccasionallyasmoresevereepisodicoutbreaks.Weather
patternsmayenhancepatternsofmortalityorrecruitment,shiftingstandcompositionand
structureonalocalorregionalscale(Eisenhart2004,Breshearsetal.2005,Shawetal.2005).
CCVA Scoring
Exposure‐Sensitivity (Potential Impact) Rank
PercentColoradoacreswithprojectedtemp>max&pptdelta<5%20.9%
InitialExposure‐SensitivityRankModerate
PercentColoradoacreswithtemp<=max&pptdelta<5%morethan50%?No(43.5%)
FinalExposure‐SensitivityRankModerate
Exposuretotemperaturechange
Underprojectedmid‐centurytemperatures,about23%ofthecurrentrangeofpinyon‐juniper
woodlandinColoradowouldexperienceannualmeantemperaturesabovethecurrentstatewide
maximum.
Exposuretoprecipitationchange
About64%ofpinyon‐juniperwoodlandinColoradowillbeexposedtoeffectivelydrierconditions
evenunderunchangedorslightlyincreasedprecipitationprojectedformid‐century.
Sensitivityofecosystemtotemperatureandprecipitation
Theseevergreenwoodlandsareadaptedtocoldwinterminimumtemperaturesandlowrainfall,
andareoftentransitionalbetweengrasslandordesertshrublandandmontaneconiferecosystems
(Brown1994,Peet2000).Thepinyon‐juniperecosystemhaslargeecologicalamplitude;warmer
conditionsmayallowexpansion,ashasalreadyoccurredinthepastcenturies,aslongasthereare
periodiccooler,wetteryearsforrecruitment.Increaseddroughtmaydrivefiresandinsect
66ColoradoNaturalHeritageProgram©2015
outbreaks,fromwhichthesewoodlandswouldbeslowtorecover.A40%declineinpinyonpine
coneproductionwasassociatedwithanaverage2.3°FincreaseinsummertemperaturesinNew
MexicoandOklahomasites(Redmondetal.2012).Warmingtemperaturesmayreducerecruitment
forpinyonpine,andmightincreasemortalityindrought‐stressedtrees(Adamsetal.2009).
Bargeretal.(2009)foundthatpinyonpinegrowthwasstronglydependentonsufficient
precipitationpriortothegrowingseason(winterthroughearlysummer),andcoolerJune
temperatures.Bothofthesevariablesarepredictedtochangeinadirectionthatislessfavorablefor
pinyonpine.Droughtcanresultinwidespreadtreedie‐off,especiallyofthemoresusceptible
pinyonpine(Breshearsetal.2008).Cliffordetal.(2013)detectedastrongthresholdat23.6in(60
cm)cumulativeprecipitationoveratwo‐yeardroughtperiod(i.e.,essentiallynormalannual
precipitationforpinyonpine).Sitesabovethisthresholdexperiencedlittlepinyondie‐off,while
sitesreceivinglessprecipitationincludedareaswithhighlevelsofmortality.Mortalityofpinyon
treeswasextensiveintheareaduringthe2002‐2003droughtandbarkbeetleoutbreak,butin
areaswherejuniperandshrubspeciesprovidemicrositesforseedlingestablishment,pinyonmay
beabletopersist(RedmondandBarger2013).Patternsofprecipitationandtemperature(i.e.,cool,
wetperiods)appeartobemoreimportantinrecruitmenteventsthanhistoryoflivestockgrazing
(Bargeretal.2009).
Resilience and Adaptive Capacity Rank
OverallScore: 0.41Rank: Low
Thestatewiderangeofannualaverageprecipitationisabout10‐23in(25‐60cm),withameanof
16in(40cm),similartosagebrushshrubland.Growingseasontemperaturesaregreaterinthe
rangeofpinyon‐juniperthanformanyotherwoodyvegetationtypesinColorado.
Extendeddroughtcanincreasethefrequencyandintensityofinsectoutbreaksandwildfire.Pinyon
aresusceptibletothefungalpathogenLeptographiumwagenerivar.wageneri,whichcausesblack
stainrootdisease,andtoinfestationsofthepinyonipsbarkbeetle(Ipsconfusus)(KearnsandJacobi
2005).Thedifferentialsusceptibilityofpinyonandjunipertodroughtandinsectoutbreakscould
eventuallyresultinthesewoodlandsbeingdominatedbyjuniper.
Bioclimaticenvelopeandrange
Averagedcategoryscore:0.76
TheNorthAmericandistributionofthisecosystemiscenteredintheColoradoPlateau,generally
southwestofColorado.Pinyon‐juniperwoodlandsoccuratfoothillandlowermontaneelevations
throughoutcentralandwesternColorado,andhaveafairlywideecologicalamplitude.Statewide,
theannualaverageprecipitationrangeforpinyon‐juniperwoodlandincludesabout44%of
Colorado’soverallprecipitationrange.Growingseasonlengthforthesewoodlandsofwarm,dry
areascoversabout60%ofthestatewiderangeofgrowingdegreedays.
Growthformandintrinsicdispersalrate
Score:0
ClimateChangeVulnerabilityAssessmentforColoradoBLM67
Thetreegrowthformandslowdispersalrateofthedominantconiferspeciesgivethisecosystema
lowresiliencescoreinthiscategory.Pinyonpinestandsareslowtorecoverfromintensefires;the
speciesreproducesonlyfromshort‐livedseedsandrecoveryisdependentonseedsourcesand/or
adequatedispersal,aswellassuitablemicrosites(e.g.,undercoveroftreesorshrubs)for
establishment(Floydetal.2015).Junipersarealsoslow‐growing,andsusceptibletobeingkilledby
fire.
Vulnerabilitytoincreasedattackbybiologicalstressors
Score:0
PinyonaresusceptibletothefungalpathogenLeptographiumwagenerivar.wageneri,whichcauses
blackstainrootdisease(primarilyonmoremesicsites),andtoinfestationsofthepinyonipsbark
beetle(Ipsconfusus)(KearnsandJacobi2005),whichhascausedextensivemortalityinpinyon‐
juniperhabitatsinsouthernColorado.Extendeddroughtcanincreasethefrequencyandintensity
ofinsectoutbreaks.
Vulnerabilitytoincreasedfrequencyorintensityofextremeevents
Score:0.7
Pinyonpinestandsareslowtorecoverfromintensefires;thespeciesreproducesonlyfromseed
andrecoveryisdependentonseedsourcesand/oradequatedispersal.Juniperarealsoslow‐
growing,andsusceptibletobeingkilledbyfire.Extendeddroughtcanincreasethefrequencyand
intensityofbothinsectoutbreaksandwildfire.
Otherindirecteffectsofnon‐climatestressors–landscapecondition
Score:0.59
Pinyon‐juniperhabitatsinColoradohavebeenmoderatelyimpactedbyanthropogenicdisturbance.
Ongoingbutlimitedthreatsfromurban,exurban,andcommercialdevelopmentareprimarilyinthe
southcentralandsouthwesternportionsofColorado,wheretowns,roads,andutilitycorridorsare
oftenincloseproximitytopinyon‐juniperwoodlands.Aswithotherhabitatsinthewildland‐urban
interface,areasneardevelopedareasaremostlikelytobethreatenedbytheeffectsoffire
suppression,whilemoreremoteareasaregenerallyingoodcondition.Livestockgrazinghas
degradedtheunderstorygrassesofsomestands,andinvasivecheatgrass(Bromustectorum)has
becomeestablishedinsomeareas.Treeremovalbychaining,orcuttingforfirewoodisaminor
sourceofdisturbancewithinthesewoodlands,butmaydramaticallychangethehabitatwhereit
hasoccurred.MilitarytrainingactivitiesareasourceofdisturbancetothishabitatatFortCarson
andPinyonCanyonManeuverSite.Oilandgasdevelopment,withassociatedroads,pipeline
corridors,andinfrastructure,isanongoingsourceofdisturbanceandfragmentationformost
pinyon‐juniperhabitats.
68ColoradoNaturalHeritageProgram©2015
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Reid,M.S.,K.A.Schulz,P.J.Comer,M.H.Schindel,D.R.Culver,D.A.Sarr,andM.C.Damm.1999.Analliancelevel
classificationofvegetationofthecoterminouswesternUnitedStates.AreporttotheUniversityofIdahoCooperativeFish
andWildlifeResearchUnitandNationalGapAnalysisPrograminfulfillmentofcooperativeagreement1434‐HQ‐97‐AG‐
01779.TheNatureConservancy,WesternConservationScienceDepartment,BoulderCO.Compactdisk.
Romme,W.H.,C.D.Allen,J.D.Bailey,W.L.Baker,B.T.Bestelmeyer,P.M.Brown,K.S.Eisenhart,M.L.Floyd,D.W.Huffman,
B.F.Jacobs,R.F.Miller,E.H.Muldavin,T.W.Swetnam,R.J.Tausch,andP.J.Weisberg.2009.Historicalandmodern
disturbanceregimes,standstructures,andlandscapedynamicsinpiñon‐junipervegetationofthewesternUnitedStates.
RangelandEcologyandManagement62:203‐222.
Ronco,F.P.,Jr.1990.PinusedulisEngelm.pinyon.In:Burns,RussellM.;Honkala,BarbaraH.,technicalcoordinators.Silvics
ofNorthAmerica.Volume1.Conifers.Agric.Handb.654.Washington,DC:U.S.DepartmentofAgriculture,ForestService:
327‐337
Shaw,J.D.,B.E.Steed,andL.T.Deblander.2005.Forestinventoryandanalysis(FIA)annualinventoryanswersthe
question:whatishappeningtopinyonjuniperwoodlands?JournalofForestry103:280–285.
Springfield,H.W.1976.Characteristicsandmanagementofsouthwesternpinyon‐juniperColoradoStateUniversity,Fort
Collins,CO.181pp.
TauschR.J.1999.Historicpinyonandjuniperwoodlanddevelopment.In:S.B.MonsenandR.Stevens[eds.].Proceedings
oftheConferenceonEcologyandManagementofPinyon‐JuniperCommunitieswithintheInteriorWest.Ogden,UT,USA:
USDepartmentofAgriculture,ForestService,RockyMountainResearchStation.p.12–19.
Woodin,H.E.,andA.A.Lindsey.1954.Juniper‐pinyoneastoftheContinentalDivide,asanalyzedbythepine‐strip
method.Ecology35:473‐489.
West,N.E.1999.Distribution,composition,andclassificationofcurrentJuniper‐Pinyonwoodlandsandsavannasacross
westernNorthAmerica.Pages20‐23inS.B.MonsenandR.Stevens,eds.,Proceedings:ecologyandmanagementof
pinyon‐junipercommunitieswithintheInteriorWest.U.S.Dept.Agric.,ForestService,RockyMountainResearchStation,
Proc.RMRS‐P‐9Ogden,UT.

70ColoradoNaturalHeritageProgram©2015
PONDEROSA
Forestsandwoodlandsdominatedbyponderosapine
S.Neid
extentexaggeratedfordisplay
Climate Vulnerability Rank: Moderate
Vulnerability summary
Key Vulnerabilities:Increaseddroughtintensityand/orfrequencyislikelytoincreasetheimpactoffire
andinsectoutbreaksinponderosaforests.Areasinthewildland‐urbaninterfacearemostproblematic.
Ponderosapineforestsandwoodlandsarerankedmoderately
vulnerabletotheeffectsofclimatechangebymid‐century.
Primaryfactorscontributingtothisrankingaretheexposureof
largeareasofthishabitattowarmertemperaturesthatarelikely
tointeractwithforeststressors(mountainpinebeetle,drought,
andfire)thatare,inturn,exacerbatedbywarm,dryconditions.
Distribution
ThiswidespreadecosystemismostcommonthroughoutthecordilleraoftheRockyMountains,but
isalsofoundintheColoradoPlateauregion,westintoscatteredlocationsintheGreatBasin,and
northintosouthernBritishColumbia.Thesematrix‐formingwoodlandsoccuratthelower
treeline/ecotonebetweengrasslandorshrublandandmoremesicconiferousforests,typicallyin
warm,dry,exposedsites.
ClimateChangeVulnerabilityAssessmentforColoradoBLM71
Characteristic species
Ponderosapine(Pinusponderosa)isthepredominantconifer;Douglas‐fir(Pseudotsugamenziesii),
pinyonpine(Pinusedulis),andjuniper(Juniperusspp.)mayalsobepresentinthetreecanopy.The
understoryisusuallyshrubby,withSaskatoonservicebery(Amelanchieralnifolia),blacksagebrush
(Artemisianova),bigsagebrush(Artemisiatridentata),kinnikinnick(Arctostaphylosuva‐ursi),
mountainmahogany(Cercocarpusmontanus),chokecherry(Prunusvirginiana),antelope
bitterbrush(Purshiatridentata),Gambeloak(Quercusgambelii),andmountainsnowberry
(Symphoricarposoreophilus)beingcommonspecies.Bunchgrassesincludingbluebunchwheatgrass
(Pseudoroegneriaspicata)andspeciesofneedle‐and‐thread(Hesperostipa),needlegrass
(Achnatherum),fescue(Festuca),muhly(Muhlenbergia),andgrama(Bouteloua)arecommon
understorygrasses.
Grace'swarbler,Pygmynuthatch,andFlammulatedowlareindicatorsofahealthyponderosapine
woodland.
Environment
Thisecosystemoccursatthelowertreeline/ecotonebetweengrasslandorshrublandandmore
mesicconiferousforeststypicallyinwarm,dry,exposedsitesatelevationsrangingfrom6,500‐
9,200ft(1,980‐2,800m).Itcanoccuronallslopesandaspects,however,itcommonlyoccurson
moderatelysteeptoverysteepslopesorridgetops.Thisecosystemoccursonsoilsderivedfrom
igneous,metamorphic,andsedimentarysubstrates(YoungbloodandMauk1985).Characteristic
soilfeaturesincludegoodaerationanddrainage,coarsetextures,circumneutraltoslightlyacidpH,
anabundanceofmineralmaterial,andperiodsofdroughtduringthegrowingseason.Surface
texturesarehighlyvariableinthisecosystemrangingfromsandtoloamandsiltloam.Exposed
rockandbaresoilconsistentlyoccurtosomedegreeinalltheassociations.Annualprecipitationis
8‐24in(25‐60cm),mostlythroughwinterstormsandsomemonsoonalsummerrains.Typicallya
seasonaldroughtperiodoccursthroughoutthissystemaswell.
Dynamics
Ponderosapineisadrought‐resistantandshade‐intolerantconiferwhichoftenformsthelower
treelineinthemajormountainrangesofthewesternUnitedStates.Historically,groundfiresand
droughtwereinfluentialinmaintainingopen‐canopyconditionsinthesewoodlands.With
settlementandsubsequentfiresuppression,occurrenceshavebecomedenser.Presently,many
occurrencescontainunderstoriesofmoreshade‐tolerantspecies,suchasDouglas‐firand/orwhite
fir(Abiesconcolor)aswellasyoungercohortsofponderosapine.Thesestructuralchangeshave
affectedfuelloadsandalteredfireregimes.Presettlementfireregimeswereprimarilyfrequent(5‐
15yearreturnintervals),low‐intensitygroundfirestriggeredbylightningstrikesordeliberately
setfiresbyNativeAmericans.Withfiresuppressionandincreasedfuelloads,fireregimesarenow
lessfrequentandoftenbecomeintensecrownfires,whichcankillmatureponderosapine(Reidet
al.1999).
72ColoradoNaturalHeritageProgram©2015
CCVA Scoring
Exposure‐Sensitivity (Potential Impact) Rank
PercentColoradoacreswithprojectedtemp>max&pptdelta<5%0.9%
InitialExposure‐SensitivityRankLow
PercentColoradoacreswithtemp<=max&pptdelta<5%morethan50%?Yes(69.4%)
FinalExposure‐SensitivityRankModerate
Exposuretotemperaturechange
Underprojectedmid‐centurytemperatures,about1%ofthecurrentrangeofponderosawoodland
inColoradowouldexperienceannualmeantemperaturesabovethecurrentstatewidemaximum.
Exposuretoprecipitationchange
About70%ofponderosapinewoodlandinColoradowillbeexposedtoeffectivelydrierconditions
evenunderunchangedorslightlyincreasedprecipitationprojectedformid‐century.
Sensitivityofecosystemtotemperatureandprecipitation
Ponderosapineoccupiesrelativelydry,nutrient‐poorsitescomparedtoothermontaneconifers,
butshowswideecologicalamplitudethroughoutitsdistribution.Rehfeldtetal.(2012)wereableto
predictthedistributionofponderosapinelargelythroughtheuseofsummerandwinter
precipitation,andsummertemperatures(asgrowingdegreedays>5°C).Althoughperiodic
seasonaldroughtischaracteristicacrosstherangeofponderosapine,thisspeciesisgenerally
foundwhereannualprecipitationisatleast13inches(Barrettetal.1980,Thompsonetal.2000).
PonderosastandstothesouthofColoradowereprimarilyreliantonwinterprecipitation
(Kerhoulasetal.2013),whilegrowthofFrontRangestandswascorrelatedwithspringandfall
moisture(LeagueandVeblen2006),indicatingsomevariabilityintheabilityofponderosapineto
takeadvantageofseasonalwateravailability,dependingonsitefactorsandstandhistory.
Consequently,vulnerabilityofponderosaforeststochangesinprecipitationpatternsmaydiffer
accordingtotheirlocationinColorado.
Ponderosapineisabletotoleratefairlywarmtemperaturesaslongasthereisenoughmoisture,
especiallyinthegrowingseason.Optimalgerminationandestablishmentconditionsoccurwhen
temperaturesareabove50°Fandmonthlyprecipitationisgreaterthan1inch(Shepperdand
Battaglia2002).Significantrecruitmenteventsmayoccuronburnedareaswhenconditionsare
wetterthannormalafterafireyear,butnormalprecipitationmayalsobesufficientforseedling
establishmentinsuchcases(Mastetal.1998).Inlowerelevationponderosawoodlandsofthe
ColoradoFrontRange,episodicrecruitmentofponderosapinewasassociatedwithhighspringand
fallmoistureavailabilityduringElNiñoevents(LeagueandVeblen2006).Acorrelationbetween
droughtandlowratesofponderosaseedlingrecruitmenthasalsobeenidentifiedthroughoutthe
westernGreatPlains(Kayeetal.2010).Droughtincombinationwithfutureprojectedhigher
temperaturesislikelytoreduceponderosapineregeneration,especiallyindrier,lowerelevation
areas.TheworkofBrownandWu(2005)suggeststhatcoincidentconditionsofsufficientmoisture
ClimateChangeVulnerabilityAssessmentforColoradoBLM73
andfewerfiresareimportantforwidespreadrecruitmentepisodesofponderosapine;such
conditionsmaybecomelesslikelyunderfutureclimatescenarios.
Increaseddroughtmaydrivefiresandinsectoutbreaks.Relativeproportionsofassociatedspecies
(e.g.,otherconifers,aspen,understoryshrubsandgrasses)inponderosastandsmaychange.This
ecosystemiswelladaptedtowarm,dryconditionsifprecipitationisnottoomuchreduced,and
maybeabletoexpandintohigherelevations.
Althoughclimatechangemayalterfireregimesslightlybyaffectingthecommunitystructure,fireis
notexpectedtohaveasevereimpactinthefutureforthesestands,andmayactuallybebeneficial
insomeareasifitrestoressomepre‐settlementconditions(CovingtonandMoore1994).These
forestsaresusceptibletooutbreaksofthemountainpinebeetleandmistletoeinfestations,bothof
whichmaybeexacerbatedbyincreaseddrought.Impactsofnativegrazersordomesticlivestock
couldalsoalterunderstorystructureandcomposition,andhavethepotentialtonegativelyimpact
soilstability(Allenetal.2002).Whileponderosapineforestsmaybeabletoexpandupwardsin
elevationorremaininthesamevicinityifprecipitationdoesn’tdrasticallychange,thedensityof
somestandsmaydecreaseduetoareductioninavailablesoilmoisture.Standsoflowerelevations
andsouthwestern‐facingslopesaremostlikelytoexperiencereducedextentofponderosapine
forests,withthepotentialforreplacementbygrassland,shrublandorpinyon‐juniperwoodland.
Resilience and Adaptive Capacity Rank
OverallScore: 0.54Rank: Moderate
Bioclimaticenvelopeandrange
Averagedcategoryscore:0.76
Ponderosawoodlandsarenotfoundathighelevations,butinsteadformabroadzoneofconiferous
forestalongthesouthernflankoftheSanJuanMountains,aswellasalongtheeasternmountain
front,generallyatelevationsbetween6,000and9,000ft.Thesewoodlandsareinwithinthecentral
portionoftheirNorthAmericandistributioninColorado.Annualprecipitationissimilartothatfor
oakshrubland,andponderosaforestsarefoundin50%ofColorado’soverallprecipitationrange.
Ponderosaoccursin50%ofgrowingseasonlengthsacrossthestate.
Growthformandintrinsicdispersalrate
Score:0
Thetreegrowthformandslowdispersalrateofponderosapinegivethisecosystemalow
resiliencescoreinthiscategory.Althoughseedsaretypicallynotdispersedveryfar,ponderosa
pineisoftenpresentinmixedconiferstands;theseareasmayprovideaseedbankforregeneration
orashifttoponderosapine.Recruitmentisepisodic,dependingonprecipitationanddisturbance
patterns.
Vulnerabilitytoincreasedattackbybiologicalstressors
Score:0.7
74ColoradoNaturalHeritageProgram©2015
Theseforestsaresusceptibletooutbreaksofthemountainpinebeetle(Dendroctonusponderosae)
andmistletoeinfestations,bothofwhichmaybeexacerbatedbyincreaseddrought.Mountainpine
beetlehascausedextensivemortalityinponderosapinehabitatsthroughoutColorado,although
thecurrentoutbreakappearstobesubsiding.Impactsofnativegrazersordomesticlivestock,and
thespreadofinvasivegrassescouldalsoalterunderstorystructureandcomposition,withthe
potentialtonegativelyimpactsoilstability(Allenetal.2002).
Vulnerabilitytoincreasedfrequencyorintensityofextremeevents
Score:0.7
Ponderosapineiswelladaptedtosurvivefrequentsurfacefires,andmixed‐severityfiresare
characteristicinthesecommunities(Arno2000).Althoughclimatechangemayalterfireregimes
slightlybyaffectingthecommunitystructure,fireisnotexpectedtohaveasevereimpactinthe
futureforthesestands,andmayactuallybebeneficialinsomeareasifitrestoressomepre‐
settlementconditions(CovingtonandMoore1994).Aprojectedincreaseinthefrequencyof
droughtconditionsislikelytoexacerbatebothfireandinsectoutbreaks,andchangethestructure
andcompositionofponderosawoodlands.
Otherindirecteffectsofnon‐climatestressors–landscapecondition
Score:0.54
PonderosapinelandscapesinColoradohavebeenmoderatelyimpactedbyanthropogenic
activities.Urbanandexurbandevelopmentareaprimarythreattoponderosapinehabitat,
especiallyalongtheFrontRange,butalsoinotherpartsofthestate.Increasingdevelopmenthas
ledtoanextensivewildland‐urbaninterfaceinponderosahabitat,aswellasfragmentationof
standsinexurbanareasduetohousing,roads,andutilitycorridors;thistrendislikelytocontinue
(Theobald2005).Oilandgasdevelopment,mining,andloggingareminorsourcesofdisturbance
andfragmentationinponderosahabitat.
Ponderosaforestandwoodlandhistoricallyexperiencedrelativelyfrequentlowintensityfiresthat
controlledthedensity,age,andstructureofstands.Withfiresuppression,ponderosahasincreased
intofoothillsgrassland,standshavegreatlyincreasedindensity,andopenponderosasavanna
habitathasdecreased.Increasedtreedensityandfuelaccumulationhasresultedinmoresevere
firesinthishabitat,aswellasincreasedoccurrenceofmountainpinebeetleanddwarfmistletoe
infestation.Thealterationofnaturalfireregimesthroughfiresuppressionisanongoingthreatfor
ponderosahabitatwhereitisneardevelopedareas.
Literature Cited
Allen,C.D.,M.Savage,D.A.Falk,K.F.Suckling,T.W.Swetnam,T.Schulke,P.B.Stacey,P.Morgan,M.Hoffman,AndJ.T.
Klingel.2002.Ecologicalrestorationofsouthwesternponderosapineecosystems:abroadperspective.Ecological
Applications12:1418–1433.
Arno,S.F.2000.Fireinwesternforestecosystems.Chapter5inBrown,J.K.andJ.K.Smith,eds.Wildlandfirein
ecosystems:effectsoffireonflora.Gen.Tech.Rep.RMRS‐GTR‐42‐vol.2.Ogden,UT:U.S.DepartmentofAgriculture,Forest
Service,RockyMountainResearchStation.257p.
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Barrett,J.W.,P.M.McDonald,F.RoncoJr,andR.A.Ryker.1980.Interiorponderosapine.In:Eyer,F.H.,ed.Forestcover
typesoftheUnitedStatesandCanada.Washington,DC:U.S.DepartmentofAgriculture,ForestService:114‐115.
Brown,P.M.andR.Wu.2005.Climateanddisturbanceforcingofepisodictreerecruitmentinasouthwesternponderosa
pinelandscape.Ecology86:3030‐3038.
Covington,W.W.andM.M.Moore.1994.Southwesternponderosaforeststructure:changessinceEuro‐American
settlement.JournalofForestry92:39–47.
KayeM.W.,C.A.WoodhouseandS.T.Jackson.2010.Persistenceandexpansionofponderosapinewoodlandsinthewest‐
centralGreatPlainsduringthepasttwocenturies.JournalofBiogeography37:1668‐1683.
Kerhoulas,L.P.,T.E.Kolb,andG.W.Koch.2013.Treesize,standdensity,andthesourceofwaterusedacrossseasonsby
ponderosapineinnorthernArizona.ForestEcologyandManagement289:425‐433.
League,K.andT.Veblen.2006.ClimaticvariabilityandepisodicPinusponderosaestablishmentalongtheforest‐
grasslandecotonesofColorado.ForestEcologyandManagement228:98‐107.
Mast,J.N.,T.T.Veblen,andY.B.Linhart.1998.Disturbanceandclimaticinfluencesonagestructureofponderosapineat
thepine/grasslandecotone,ColoradoFrontRange.JournalofBiogeography.25:743‐755.
Rehfeldt,G.E.,N.L.Crookston,C.Saenz‐Romero,andE.M.Campbell.2012.NorthAmericanvegetationmodelforland‐use
planninginachangingclimate:asolutionoflargeclassificationproblems.EcologicalApplications22:119‐141.
Reid,M.S.,K.A.Schulz,P.J.Comer,M.H.Schindel,D.R.Culver,D.A.Sarr,andM.C.Damm.1999.Analliancelevel
classificationofvegetationofthecoterminouswesternUnitedStates.UnpublishedfinalreporttotheUniversityofIdaho
CooperativeFishandWildlifeResearchUnitandNationalGapAnalysisProgram,infulfillmentofCooperativeAgreement
1434‐HQ‐97‐AG‐01779.TheNatureConservancy,WesternConservationScienceDepartment,Boulder,CO.
Shepperd,W.D.andM.A.Battaglia.2002.Ecology,Silviculture,andManagementofBlackHillsPonderosaPine.General
TechnicalReportRMRS‐GTR‐97.USDAForestServiceRockyMountainResearchStation,FortCollins,CO.112
Theobald,D.M.2005.LandscapepatternsofexurbangrowthintheUSAfrom1980to2020.EcologyandSociety10:32
Thompson,R.S.,K.H.Anderson,andP.J.Bartlein.2000.Atlasofrelationsbetweenclimaticparametersanddistributionsof
importanttreesandshrubsinNorthAmerica.U.S.GeologicalSurveyProfessionalPaper1650‐A.
Youngblood,A.P.,andR.L.Mauk.1985.ConiferousforesthabitattypesofcentralandsouthernUtah.USDAForest
Service,IntermountainResearchStation.GeneralTechnicalReportINT‐187.Ogden,UT.89pp
76ColoradoNaturalHeritageProgram©2015
SPRUCE‐FIR
Dry‐mesicandmesicforestsdominatedbyEngelmannspruceandsubalpinefir
R.Rondeauextentexaggeratedfordisplay
Climate Vulnerability Rank: Moderate
Vulnerability summary
Key Vulnerabilities:Increaseddroughtintensityand/orfrequencyislikelytoincreasetheimpactoffire
andinsectoutbreaksinsubalpineforests.Theseforestsrecoverslowlyduetoslowdispersalandashort
growingseason.
Climatechangeprojectionsindicateanincreaseindroughtsand
fastersnowmelt,whichcouldincreaseforestfirefrequencyand
extent,aswellasinsectoutbreakswithinthisecosystem.Itisnot
knownifspruce‐firforestswillbeabletoregenerateundersuch
conditions,especiallyinlowerelevationstands,andthereisa
potentialforareductionorconversiontootherforesttypes,
dependingonlocalsiteconditions.
Thevulnerabilityoftheseforeststowarmertemperatures,
drought,andincreasedmortalityfrominsectoutbreaksare
primaryfactorscontributingtovulnerability.Therestrictionof
thishabitattohigherelevationsanditsrelativelynarrow
biophysicalenvelope,slow‐growth,andpositionnearthe
southernendofitsdistributioninColoradoareadditional
factors.However,theremaybealagtimebeforetheeffectsof
changingclimateareevident.
ClimateChangeVulnerabilityAssessmentforColoradoBLM77
Thelagtimeofthecurrenttreelinepositionbehindclimatechangeisestimatedtobe50‐100+
years,duetotherarityofrecruitmentevents,theslowgrowthandfrequentsetbacksfortreesin
theecotone,andcompetitionwithalreadyestablishedalpinevegetation(Körner2012).However,
onthebasisofhistoricevidence,treelinecanbeexpectedtomigratetohigherelevationsas
temperatureswarm,aspermittedbylocalmicrositeconditions(Smithetal.2003,Richardsonand
Friedland2009,Grafiusetal.2012).Thegradualadvanceoftreelineisalsolikelytodependon
precipitationpatterns,particularlythebalanceofsnowaccumulationandsnowmelt(Rochefortet
al.1994).Ouranalysisindicatedthatspruce‐firforestsinColoradohavemoderatevulnerabilityto
theeffectsofclimatechangebymid‐century.
Distribution
Spruce‐firdry‐mesicandmoist‐mesicforestecosystemsformtheprimarymatrixsystemsofthe
montaneandsubalpinezonesoftheSouthernRockyMountainsecoregion,andaccountfora
substantialpartofthesubalpineforestsoftheCascadesandRockyMountainsfromsouthern
BritishColumbiaeastintoAlberta,southintoNewMexicoandtheIntermountainregion.Spruce‐fir
forestalsoshowschangeswithlatitudeincludingtreelineelevation,speciescomposition,and
dominance.Subalpinefir(Abieslasiocarpa)decreasesinimportancerelativetoEngelmannspruce
(Piceaengelmannii)withincreasingdistancefromtheregionofMontanaandIdahowheremaritime
airmassesinfluencetheclimate.Firincreasesinimportancewithincreasinglatitude,andshares
dominancewithspruceattreelineoverthenorthernhalfoftheSouthernRockyMountains
ecoregion.Treelineoccursatover12,450ft(3800m)atthesouthernendoftheSouthernRocky
Mountainecoregion,butdoesnotexceed11,150ft(3400m)atthenorthernend(Peet1978).
Individualcommunitytypesmaybematrixorlargepatchincharacter,thoughmosttypicallyoccur
asamosaicoflargepatchesacrossthelandscape.Spruce‐firdominatedstandsoccuronallbutthe
mostxericsitesabove10,000ft(3,100m),andincool,shelteredvalleysatelevationsaslowas
8,200ft(2,500m).Therelativedominanceofthetwocanopytreespeciesandtheunderstory
compositionvarysubstantiallyoveragradientfromexcessivelymoisttoxericsites(Peet1981).
Themesicspruce‐firtypeoccursoncool,sheltered,butwell‐drainedsitesabove8,850ft(2,700m).
Openslopesabove9,850ft(3,000m)aretypicallycharacterizedbyamorexericspruce‐firtype,
withvaryingamountsoflodgepoleandlimberpine.
Characteristic species
Engelmannspruceandsubalpinefirdominatethecanopy,eithertogetheroralone.Lodgepolepine
(Pinuscontorta)iscommoninmanyoccurrencesasaremixedconifer/quakingaspen(Populus
tremuloides)stands.UnderstoryspeciesmayincludeGeyer'ssedge(Carexgeyeri),commonjuniper
(Juniperuscommunis),creepingbarberry(Mahoniarepens),Jacob's‐ladder(Polemonium
pulcherrimum)orwhortleberry(Vacciniumspp.).Moremesicunderstorymayincludered
baneberry(Actaearubra),sprucefirfleabane(Erigeroneximius),thimbleberry(Rubusparviflorus),
yellowdotsaxifrage(Saxifragabronchialis),oralpineclover(Trifoliumdasyphyllum),amongother
species.
78ColoradoNaturalHeritageProgram©2015
Pinemartensareprimarilyaspruce‐firobligatespeciesthatrequireahealthyandsizeable
occurrenceofmatureforestandareanindicatorofahealthyandviableoccurrenceofthespruce‐fir
ecosystem
Environment
Thesearethematrixforestsofthesubalpinezone,withrangewideelevationsrangingfrom5,000‐
11,000ft(1,525to3,355m).Sitesarecoldyear‐round,andprecipitationispredominantlyinthe
formofsnow,whichmaypersistuntillatesummer.Moist‐mesicoccurrencesaretypicallyfoundin
locationswithcold‐airdrainageorponding,orwheresnowpackslingerlateintothesummer,such
asnorth‐facingslopesandhigh‐elevationravines.Theycanextenddowninelevationbelowthe
subalpinezoneinplaceswherecold‐airpondingoccurs;northerlyandeasterlyaspects
predominate.Theseforestsarefoundongentletoverysteepmountainslopes,high‐elevation
ridgetopsandupperslopes,highplateaus,basins,alluvialterraces,well‐drainedbenches,and
inactivestreamterraces.
Dynamics
Fire,spruce‐beetleoutbreaks,avalanches,andwindthrowallplayanimportantroleinshapingthe
dynamicsofspruce‐firforests.Firesinthesubalpineforestaretypicallystandreplacing,resulting
intheextensiveexposureofmineralsoilandinitiatingthedevelopmentofnewforests.Stand
replacingfiresareestimatedtooccuratintervalsofabout300yearsfordry‐mesicareas,and
longer(350‐400years)formoremesicsites(RommeandKnight1981).Firereturnintervals,
intensity,andextentnaturallydependonavarietyoflocalenvironmentalfactors.Dependingon
siteconditions,spruceorlodgepolepinemayinitiallydominatethepost‐firesite,incombination
withlimberpine,andquakingaspen(DonneganandRebertus1999).Firisgenerallytheleast
abundantforseveraldecadesafterfire,butisabletoestablishinlow‐lightconditionsonforest
litter,andgraduallyincreasesinabundance(Veblenetal.1991).
Sprucebeetle(Dendroctonusrufipennis)outbreaksmaybeevenmoresignificantthanfireinthe
developmentofspruce‐firforests(Weedetal.2013).Whenlargersprucetreesarekilledbyspruce
beetleinfestation,smallerdiametersprucetreesandsubalpinefirtreesareabletoincreasegrowth
andcontinuetodominatethestand(Veblenetal.1991).Inadditiontofiresandbeetlekill,wind
disturbanceinspruce‐firforestshasbeenwelldocumented(Schauppetal.1999).Blowdowns
involvingmultipletreefallsaddtothemosaicofspruce‐firstands.Underanaturaldisturbance
regime,subalpineforestswereprobablycharacterizedbyamosaicofstandsinvariousstagesof
recoveryfromdisturbance,withold‐growthjustonepartofthelargerforestmosaic(Peet1981).
ClimateChangeVulnerabilityAssessmentforColoradoBLM79
CCVA Scoring
Exposure‐Sensitivity (Potential Impact) Rank
PercentColoradoacreswithprojectedtemp>max&pptdelta<5%0.2%
InitialExposure‐SensitivityRankLow
PercentColoradoacreswithtemp<=max&pptdelta<5%morethan50%?No(40.8%)
FinalExposure‐SensitivityRankLow
Exposuretotemperaturechange
Underprojectedmid‐centurytemperatures,lessthan1%ofthecurrentrangeofspruce‐firforestin
Coloradowouldexperienceannualmeantemperaturesabovethecurrentstatewidemaximum.
Exposuretoprecipitationchange
About41%ofspruce‐firforestinColoradowillbeexposedtoeffectivelydrierconditionseven
underunchangedorslightlyincreasedprecipitationprojectedformid‐century.
Sensitivityofecosystemtotemperatureandprecipitation
Spruce‐firforesttypicallydominatesthewettestandcoolesthabitatsbelowtreeline.Theseareas
arecharacterizedbylong,coldwinters,heavysnowpack,andshort,coolsummerswherefrostis
common(Uchytil1991).BothEngelmannspruceandsubalpinefiraredependentonsnowmelt
waterformostofthegrowingseason,andinlowsnowpackyearsgrowthisreduced(Huetal.
2010).
Thelengthofthegrowingseasonisparticularlyimportantforbothalpineandsubalpinezones,and
forthetransitionzonebetweenalpinevegetationandclosedforest(treeline).Treeline‐controlling
factorsoperateatdifferentscales,rangingfromthemicrositetothecontinental(Holtmeierand
Broll2005).Onaglobalorcontinentalscale,thereisgeneralagreementthattemperatureisa
primarydeterminantoftreeline.Körner(2012)attributesthedominanceofthermalfactorsatthis
scaletotherelativeconsistencyofatmosphericconditionsoverlargeareas,especiallyin
comparisontomorelocalinfluenceofsoilandmoisturefactors.Furthermore,thereappearstobea
criticaldurationoftemperaturesadequateforthegrowthoftreesinparticular(e.g.,individuals
>3mtall)thatdeterminesthelocationoftreeline.Atmorelocalscales,soilproperties,slope,aspect,
topography,andtheireffectonmoistureavailability,incombinationwithdisturbancessuchas
avalanche,grazing,fire,pests,disease,andhumanimpactsallcontributetotheformationof
treeline(RichardsonandFriedland2009,Körner2012).Patternsofsnowdepthandduration,
wind,insolation,vegetationcover,andtheautecologicaltolerancesofeachtreespeciesinfluence
theestablishmentandsurvivalofindividualswithinthetreelineecotone(Moiretal.2003,
HoltmeierandBroll2005,Smithetal.2009).IntheRockyMountains,treeestablishmentwas
significantlycorrelatedwithwarmerspring(Mar‐May)andcool‐season(Nov‐Apr)minimum
temperaturesaswell(Elliott2012).
Spruce‐firforestscurrentlyoccupycoldareaswithhighprecipitation;warmeranddrierclimate
conditionspredictedbymostmodelscouldresultinanupwardmigrationoftheseforestsintothe
80ColoradoNaturalHeritageProgram©2015
alpinezone.However,inCanadianspruce‐firforests,warmerthanaveragesummertemperatures
ledtoadecreaseingrowththefollowingyear(HartandLaroque2013).Sincespruce‐firmaybe
abletotoleratewarmersummertemperatures,thelowerextentofthishabitattypecouldremainat
currentlevelsforsometime,evenifgrowthisreduced.
Thecurrentlocationoftreelineisaresultoftheoperationofclimaticandsite‐specificinfluences
overthepastseveralhundredyears,anddoesnotexactlyreflectthecurrentclimate(Körner2012).
Thetreelinepositionlagtimebehindclimatechangeisestimatedtobe50‐100+years,duetothe
rarityofrecruitmentevents,theslowgrowthandfrequentsetbacksfortreesintheecotone,and
competitionwithalreadyestablishedalpinevegetation(Körner2012).Nevertheless,onthebasisof
historicevidence,treelineisgenerallyexpectedtomigratetohigherelevationsastemperatures
warm,aspermittedbylocalmicrositeconditions(Smithetal.2003,RichardsonandFriedland
2009,Grafiusetal.2012).Infact,treelineadvancehasalreadybeendocumentedatsitesintheSan
JuanMountains(Finketal.2014).
Furthermore,thelagtimeofdecadesorlongerfortreelinetorespondtowarmingtemperatures
mayallowthedevelopmentofnovelvegetationassociations(ChapinandStarfield1997),andmake
itdifficulttoidentifytemperatureconstraintsonthedistributionofthishabitat(Grafiusetal.
2012).Thegradualadvanceoftreelineisalsolikelytodependonprecipitationpatterns.Seedling
establishmentandsurvivalaregreatlyaffectedbythebalanceofsnowaccumulationandsnowmelt.
Soilmoisture,largelyprovidedbysnowmelt,iscrucialforseedgerminationandsurvival.Although
snowpackinsulatesseedlingsandshieldssmalltreesfromwinddesiccation,itspersistence
shortensthegrowingseasonandcanreducerecruitment(Rochefortetal.1994).
Resilience and Adaptive Capacity Rank
OverallScore: 0.34Rank: Low
Bioclimaticenvelopeandrange
Averagedcategoryscore:0.30
Spruce‐firforestsinColoradohaveawideelevationalrange,extendingfromabout8,900ftupto
over12,000ft.Althoughnotasrestrictedasalpinehabitats,spruce‐firforestsaregenerallylimited
tohigher,coolerelevations,andarealsonearthesouthernextentoftheircontinentalrangein
Colorado.Statewide,annualaverageprecipitationisonlyslightlylowerthanthatofalpine,and
theseforestshavesignificantpresencein82%ofColorado’soverallprecipitationrange.Spruce‐fir
requiresalongergrowingseasonthanalpinehabitat,butissuccessfulatmuchcoolertemperatures
thanmostotherforesttypes,coveringonly38%ofthestate’sgrowingdegreerange.Thesefactors
combinetoproducearelativelypoorresiliencescoreinthiscategory.
Growthformandintrinsicdispersalrate
Score:0
Thetreegrowthformandslowdispersalrateofthedominantconiferspeciesgivethisecosystema
lowresiliencescoreinthiscategory.Subalpinefirseedsrequirecold‐moistconditionstotrigger
ClimateChangeVulnerabilityAssessmentforColoradoBLM81
germination(Uchytil1991),andthereissomeindicationthatEngelmannspruceseedsgerminate
fasteratrelativelylowtemperatures(Smith1985),givingitacompetitiveadvantageoverlesscold‐
tolerantspecies.Underwarmerconditions,however,currentspruce‐fircommunitiesmaybe
graduallyreplacedbyamixed‐coniferforest.Therearenoobviousbarrierstothegradualdispersal
ofseedlingsintoadjacent,newlysuitablehabitat,althoughthedominantspeciesaregenerally
slow‐growing.
Vulnerabilitytoincreasedattackbybiologicalstressors
Score:0
Althoughthesesubalpineforestsarenotsusceptibletoincreasedprevalenceofinvasivespecies,
theyarevulnerabletooutbreaksofthenativepestspeciessprucebudwormandsprucebeetle.
Warmertemperatures(bothwinterandsummer)arelikelytofacilitatetheseinfestations.Warmer
wintersarecorrelatedwithreducedbeetlemortality,whilehighersummertemperaturesallowa
greaterproportionofthesprucebeetlepopulationtocompleteagenerationinasingleyear,witha
correspondinglyhigherprobabilityofpopulationoutbreak(Bentzetal.2010).Thecurrent
distributionofspruce‐firhabitatisthereforelikelytobeatincreasedriskofsignificantmortality.
Insectoutbreaksarealsotypicallyassociatedwithdroughts.
Vulnerabilitytoincreasedfrequencyorintensityofextremeevents
Score:0.5
Historicnaturalfire‐returnintervalsintheseforestshavebeenontheorderofseveralhundred
years,andthetreespeciesarenotadaptedtomorefrequentfires.Withanincreaseindroughtsand
fastersnowmelts,wecanexpectanincreaseinforestfirefrequencyandextentwithinthiszoneas
ignitionofheavyfuelloadsbecomeslesslimitedbycool,wetconditions.Itisnotknownifspruce‐
firforestswillbeabletoregenerateundersuchconditions,especiallyinlowerelevationstands,and
thereisapotentialforareductioninspruce‐firforests,atleastintheshortterm.
Otherindirecteffectsofnon‐climatestressors–landscapecondition
Score:0.89
Spruce‐firforestlandscapesinColoradoaregenerallyinverygoodcondition,wellprotected,and
minimallyimpactedbyanthropogenicdisturbance.Becausenaturalfirereturnintervalsinthese
habitatsarelong,firesuppressionhasnothadwidespreadeffectsontheconditionofspruce‐fir
habitat.Atalandscapescale,however,agestructuresofspruce‐firforestareprobablysomewhat
alteredfrompre‐settlementconditions.Spruce‐firforestsaresubjecttodisturbancebyrecreational
use,hunting,livestockgrazing,mining,andlogging,butingeneral,threatsfromhousing,roads,and
recreationaldevelopmentandsimilaranthropogenicdisturbanceareminorforspruce‐firhabitats.
Literature Cited
Alexander,R.R.1987.Ecology,silviculture,andmanagementoftheEngelmannspruce‐subalpinefirtypeinthecentral
andsouthernRockyMountains.Agric.Handb.659.Washington,DC:U.S.DepartmentofAgriculture,ForestService.144p.
82ColoradoNaturalHeritageProgram©2015
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Fink,M.,R.Rondeau,andK.Decker.2014.TreelinemonitoringintheSanJuanMountains.ColoradoNaturalHeritage
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Holtmeier,F‐K.andG.Broll.2005.Sensitivityandresponseofnorthernhemispherealtitudinalandpolartreelinesto
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Moir,W.H.,S.G.Rochelle,andA.W.Schoettle.1999.Microscalepatternsoftreeestablishmentnearuppertreeline,Snowy
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Romme,W.H.andD.H.Knight.1981.Firefrequencyandsubalpineforestsuccessionalongatopographicgradientin
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timberlines.TreePhysiology23:1101‐1112.
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Uchytil,R.J.1991.PiceaengelmanniiandAbieslasiocarpa.In:FireEffectsInformationSystem,[Online].U.S.Departmentof
Agriculture,ForestService,RockyMountainResearchStation,FireSciencesLaboratory(Producer).Available:
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Veblen,T.T.1986.AgeandsizestructureofsubalpineforestsintheColoradoFrontRange.BulletinoftheTorreyBotanical
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Veblen,T.T.,K.S.Hadley,M.S.Reid,andA.J.Rebertus.1991.Theresponseofsubalpineforeststosprucebeetleoutbreakin
Colorado.Ecology72:213‐231.
Weed,A.S.,M.P.Ayres,andJ.A.Hicke.2013.ConsequencesofclimatechangeforbioticdisturbancesinNorthAmerica
forests.EcologicalMonographs83:441‐470.

84ColoradoNaturalHeritageProgram©2015
Shrubland
Table 2.6.Keyvulnerabilities,shrublandecosystems.
Habitat Climate factor(s) Consequences Other considerations
DesertshrublandSoilmoistureConversiontoothertypeHighlyaltered
Oak&mixedmtn.
shrub
Drought,lastfrostdate
variability
Diebackwithdroughtand
latefrost;mayincreaseby
resproutingafterfire
Anthropogenicdisturbance
SagebrushDroughtIncreaseininvasivespecies
suchascheatgrass;fire
Variablebysubspecies
SandsageExtendeddroughtSoilmobilizationLossofnativebiodiversity
ClimateChangeVulnerabilityAssessmentforColoradoBLM85
DESERT SHRUBLAND
Shrubland,shrub‐steppe,dwarf‐shrubland,andsparselyvegetatedareascharacterizedbysaltbush,
rabbitbrush,winterfat,andotherxericshrubspecies
CNHP
extentexaggeratedfordisplay
Climate Vulnerability Rank: Moderate
Vulnerability summary
Key Vulnerabilities:Theinteractionofsoiltypesandprecipitationpatternslargelydeterminesthe
compositionandextentoftheseshrublands,whichmayundergoconversiontoothertypesunderfuture
climateconditions.Thealteredconditionofmanystandsisaconfoundingfactor.
Theprimaryfactorcontributingtothemoderatevulnerability
rankingofdesertshrublandsinColoradoistheextenttowhich
standshavebeenimpactedbyanthropogenicdisturbance,with
greatlyalteredspeciescompositioninmanyinstances.The
resiliencescoreforthisecosystemisotherwisehigh,and,since
thesearecommunitiesofaridlandscapes,theycouldbeless
vulnerabletoclimatechangewherestandsareingoodcondition.
However,changingsoilmoisturepatternsmayeventuallyfavor
semi‐desertgrasslandinareascurrentlyoccupiedbydesert
shrubland.
Distribution
DesertshrublandcommunitiesoccurthroughouttheintermountainwesternU.S.,andaretypically
open‐canopiedshrublandsdominatedbysaltbushspeciesorothershrubstolerantofsalineor
alkalinesoilstypicallyderivedfrommarineshales,siltstonesandclay.Forthisassessment,we
groupedshrub‐steppe,mixedsaltdesertshrub,matsaltbushshrublands,andsparselyvegetated
shalebadlandstogetherasdesertshrubland.Thesesparsetomoderatelydenselow‐growing
86ColoradoNaturalHeritageProgram©2015
shrublandsarewidespreadatlowerelevationsinColorado’swesternvalleys,butalsooccurtoa
smallerextentontheeasternplains.Desertshrublandsarefoundprimarilybetween4,500and
7,000feet,althoughshrub‐steppemayextendupto9,500feetinsomeareas.Shrub‐steppedoes
notformextensivestandsinColoradoexceptintheSanLuisValley.Pinyon‐juniperwoodlandsand
sagebrushshrublandscommonlyareadjacentattheupperelevations.
Characteristic species
Matsaltbushshrublandtypicallysupportsrelativelypurestandsoflow‐growingmatsaltbush
(Atriplexcorrugata)orGardner'ssaltbush(Atriplexgardneri).Otherdwarf‐shrubspeciesthatmay
bepresentincludebudsagebrush(Picrothamnusdesertorum)andshortspinehorsebrush
(Tetradymiaspinosa).Scatteredperennialforbsoccur,suchasdesertprincesplume(Stanleya
pinnata),eveningprimrose(Oenotheraspp.),andphacelia(Phaceliaspp.).Indianricegrass
(Achnatherumhymenoides)andalkalisacaton(Sporobolusairoides)maybepresentinswales.
Annualsmayincludedeserttrumpet(Eriogonuminflatum),andintroducedspeciessuchasAfrican
mustard(Malcolmiaafricana)andcheatgrass(Bromustectorum).Someareasareessentially
barren,orverysparselyvegetated.
Mixedsaltdesertscrubischaracterizedbythetallersaltbushspeciesshadscalesaltbush(Atriplex
confertifolia)orfourwingsaltbush(Atriplexcanescens),andmayincludewinterfat
(Krascheninnikovialanata),paledesert‐thorn(Lyciumpallidum),horsebrush(Tetradymia
canescens),andvarioussagebrush(Artemisia)species.Grassesandforbsaresparsetomoderately
dense,anddominatedbyspeciestolerantoftheharshsoils.Typicalperennialgrassesinclude
Indianricegrass,bluegrama(Boutelouagracilis),thickspikewheatgrass(Elymuslanceolatusssp.
lanceolatus),westernwheatgrass(Pascopyrumsmithii),James’galleta(Pleuraphisjamesii),
Sandbergbluegrass(Poasecunda),oralkalisacaton.
Colorado’sshrub‐steppesaregrass‐dominatedareaswithanopenshrublayer.Typicalgrass
speciesincludebluegrama,needle‐and‐thread(Hesperostipacomata),James’galleta,saltgrass
(Distichlisspicata),Indianricegrass,andalkalisacaton.Historically,theshrublayerwasdominated
bywinterfat,butthisspecieshasdecreasedundergrazingpressureinmanyareas.Winterfathas
largelybeenreplacedbyrabbitbrush(EricameriaandChrysothamnus)speciesandotherwoody
shrubs.
Environment
Desertshrublandclimateisgenerallyaridorsemi‐aridwithextremetemperaturedifferences
betweensummerandwinter.ForoccurrencesinsouthernColorado,themonsoonalperiodofmid‐
tolatesummernormallyprovidesmostoftheannualmoisture;innorthernareasprecipitationis
moreevenlyspreadthroughouttheyear,includingduringthecoldestmonths.Inthesecolddesert
shrublands,however,theyeartoyearvariationofprecipitationislikelytobegreaterthanseasonal
variablity,withresultanteffectsoninterannualvariabilityingrowthandreproductionofshrubland
species(BlaisdellandHolmgren1984).
Desertshrublandsubstratesaregenerallyshallow,typicallysalineoralkaline,fine‐texturedsoils
developedfromshaleoralluvium.Suchsoilsarepoorlydeveloped,duetothearidclimate,with
ClimateChangeVulnerabilityAssessmentforColoradoBLM87
verylowinfiltrationrates(West1983).Unvegetatedsubstrateiscommon,and,ifundisturbed,is
oftencoveredbyabiologicalsoilcrust.Althoughperennialspeciestendtosortoutalonga
moisture/salinitygradientaccordingtoindividualspeciestolerances(West1983),theredonot
appeartobeanyexceptionallynarrowtolerancesorrequirementsforapartcularsoilfactor
presentintypicaldesertshrublandplants(BlaisdellandHolmgren1984).
Dynamics
Thenaturallysparseplantcovermakestheseshrublandsespeciallyvulnerabletowaterandwind
erosion,especiallyifvegetationhasbeenimpactedbygrazingordisturbancesincludingfire.
Historically,saltdesertshrublandshadlowfirefrequency(Simonin2001),andarecharacterized
bylowfuelmassandlowsoilmoisture,whichtendstomitigatefireimpacts(Allenetal.2011).
However,increasedextentofintroducedannualgrasses,especiallycheatgrass,hasfacilitatedthe
spreadoffirebyprovidingcontinuoussurfacefuelsinmanyareas(West1994,).IntheGreatBasin,
cheatgrasshasdemonstrablyincreasedfireactivityinsagebrushshrublands(Balchetal.2013),but
lessisknownaboutfire‐sensitivityofsalinedeserttypes.FiretoleranceofAtriplexspeciesisvaried;
mostsurvivingindividualsareabletoresprout.FourwingsaltbushinNewMexicohadsevere
mortalityfromfire(62%killed),butsurvivingshrubsquicklyresproutedandeventuallyrecovered
prefirestature(Parmenter2008).Shadscaleisgenerallykilledbyfireandreliesonseedfor
revegetationofburnedareas(West1994).Althoughtheirstudydidnotincludeungrazedplotsfor
comparison,Haubensaketal.(2009)notedthat,afterfire,grazeddesertshrublandshad
significantlylowervegetationcover,andweremoreinvadedbynon‐nativespeciesincomparison
withunburnedplots.
Manyofthedominantshrubsarepalatabletodomesticlivestock,sograzingcanalterspecies
compositionaswellasincreasingerosionpotential.Incombinationwithclimaticvariability,these
disturbancesacttochangefloristiccompositionofdesertshrublandsovertime.Forexample,
winterfatwashistoricallyatypicaldominantinsemi‐desertshrubsteppe.Thispalatableshrubis
consideredadecreaserunderdomesticlivestockgrazing.Asaconsequenceofanthropogenically
inducedchangesingrazingpatterns,Greene'srabbitbrush(Chrysothamnusgreenei)isnow
dominantinSanLuisValleyshrubsteppe,althoughthewetterareasstillhavesignificantamounts
ofwinterfat.
CCVA Scoring
Exposure‐Sensitivity (Potential Impact) Rank
PercentColoradoacreswithprojectedtemp>max&pptdelta<5%30.6%
InitialExposure‐SensitivityRankModerate
PercentColoradoacreswithtemp<=max&pptdelta<5%morethan50%?No(48.0%)
FinalExposure‐SensitivityRankModerate
88ColoradoNaturalHeritageProgram©2015
Exposuretotemperaturechange
Underprojectedmid‐centurytemperatures,about37%ofthecurrentrangeofdesertshrublandin
Coloradowouldexperienceannualmeantemperaturesabovethecurrentstatewidemaximum.
Exposuretoprecipitationchange
About79%ofdesertshrublandinColoradowillbeexposedtoeffectivelydrierconditionseven
underunchangedorslightlyincreasedprecipitationprojectedformid‐century.
Sensitivityofecosystemtotemperatureandprecipitation
Thedominantdesertshrubsareabletogrowwhenevertemperaturesarefavorable,butonlyif
thereissufficientsoilmoisture.Soilmoistureaccumulationisprimarilyinwinter,andinfluences
theamountofspringplantgrowth.Ifnoadditionalmoistureisreceivedinspring,growthends,and
plantsbecomedormant.Laterrainsduringthewarmseasonmayre‐inducegrowth(Blaisdelland
Holmgren1984).Soilsaturationmaycausemortalityofthedominantshrubs(Ewingand
Dobrowolski1992).Thecharacteristicinterannualvariabilityofprecipitationindesertshrubareas,
andthedifferentlifehistorystrategies/phenologyofthecomponentspeciescanproducedramatic
differencesinshrublandappearancefromoneyeartothenext(BlaisdellandHolmgren1984).
Munsonetal.(2011)founddecreasedcanopycoverinAtriplexshrublandswithincreasing
temperature,whichtheyattributedtoincreasedevaporationandreducedwateravailabilityinthe
shale‐derivedsoils.Thus,theseshrublandsmaybeabletotoleratehighertemperaturesonlywhen
precipitationisadequate.However,insomesemi‐aridandaridsystems,temporalvariationin
wateravailabilitymaycreatepositivefeedbacksthatfacilitateencroachmentofC3woodyplant
speciesintoareasformerlydominatedbyC4grasses.Otherdesertshrubspecieswithdeeperroot
systems(e.g.,blackbrush,greasewood,mormontea,sagebrush)arebetteradaptedtoexpandinto
grassyareasthanrelativelyshallow‐rootedAtriplexspecies(Munsonetal.2011).Further
differentiationbetweenshrubspeciesintheabilitytoutilizerainfallduringparticularseasons(Lin
etal.1996)mayleadtochangesinspeciescompositionintheseshrublands.Shadscalesaltbush(A.
confertifolia)andotherdesertshrubsaretypicallydependentonspringsoilmoistureforgrowth,
andhavelowmetabolicactivityduringsummerasthesoildries(Mata‐Gonzálezetal.2014).
Resilience and Adaptive Capacity Rank
OverallScore: 0.69Rank: Moderate
Bioclimaticenvelopeandrange
Averagedcategoryscore:0.72
Desertshrublandsaregenerallyconfinedtowarm,dryhabitatswithinColorado,occupying31%of
Colorado’soverallprecipitationrangeand57%ofthestatewiderangeofgrowingdegreedays.
Theseshrublandsarenotlimitedbyelevationalconstraints,andarenotatthesouthernedgeof
theirrangeinColorado,whichgivesthemagoodresiliencescoreinthiscategory.
Growthformandintrinsicdispersalrate
Score:0.5
ClimateChangeVulnerabilityAssessmentforColoradoBLM89
Althoughthedominantshrubspeciesarelikelytobefairlyfastgrowing,lackofinformationabout
thedispersalratesofthesespeciesgivesthisecosystemanintermediateresiliencescoreforthis
category.
Vulnerabilitytoincreasedattackbybiologicalstressors
Score:0.7
Increasedinvasionbynon‐nativeannualgrassesandconsequentincreaseinfirefrequencyislikely
todepressrecruitmentofsaltdesertshrubspecies(Haubensaketal.2009).
Vulnerabilitytoincreasedfrequencyorintensityofextremeevents
Score:1
Theseshrublandsarewelladaptedtodrought,sohaveahighresiliencescoreforthiscategory.
Increasedfireeffectsarescoredinthepreviouscategoryasbeingmediatedbycheatgrassinvasion.
Otherindirecteffectsofnon‐climatestressors–landscapecondition
Score:0.51
DesertshrublandlandscapesinColoradohavebeenmoderatelyimpactedbyanthropogenic
activities.Significantportionshavebeenconvertedtoagriculturaluse,especiallyinvalleybottoms
whereirrigationisavailable.Remainingstandsaregenerallyingoodcondition,exceptforaltered
speciescompositioninareaswheregrazinghasreducedoreliminatedsomenativebunchgrasses.
Ongoinglimitedthreatsfromexurbandevelopmentorconversiontoagricultureareaminorsource
ofdisturbance,fragmentation,andhabitatlossintheremainingextentoftheseshrublands.Oiland
gasdevelopment,withassociatedroads,pipelinecorridors,andinfrastructureistheprimary
ongoingsourceofanthropogenicdisturbance,fragmentation,andlossinthishabitat.Livestock
grazinghasalteredpre‐settlementspeciescomposition,andthistrendislikelytocontinueata
reducedrate.Roadsandutilitycorridors,includingthoseassociatedwithsolarenergydevelopment
intheSanLuisValleyareanongoingsourceofdisturbance,andcanfacilitatethespreadofinvasive
plantspecies,whichhavebecomeestablishedinsomeareas.
Literature Cited
Allen,E.B.,R.J.Steers,andS.J.Dickens.2011.Impactsoffireandinvasivespeciesondesertsoilecology.Rangeland
EcologyandManagement64:450‐462.
Balch,J.K.,B.A.Bradley,C.M.D’Antonio,andJ.Gómez‐Dans.2013.Introducedannualgrassincreasesregionalfireactivity
acrossthearidwesternUSA(1980‐2009).GlobalChangeBiology19:173‐183.
Blaisdell,J.P.andR.C.Holmgren.1984.ManagingIntermountainrangelands‐salt‐desertshrubranges.USDAForest
ServiceGeneralTechnicalReportINT‐163.IntermountainForestandRangeExperimentStation,Ogden,Utah.52pp
Haubensak,K.,C.D’Antonio,andD.Wixon.2009.Effectsoffireandenvironmentalvariablesonplantstructureand
compositioningrazedsaltdesertshrublandsoftheGreatBasin(USA).JournalofAridEnvironments73:643‐650.
90ColoradoNaturalHeritageProgram©2015
Lin,G.S.L.Phillips,andJ.R.Ehleringer.1996.Monsoonalprecipitationresponsesofshrubsinacolddesertcommunityon
theColoradoPlateau.Oecologia106:8‐17.
Mata‐GonzálezR.,T.L.Evans,D.W.Martin,T.McLendon,J.S.Noller,C.Wan,andR.E.Sosebee.2014.PatternsofWaterUse
byGreatBasinPlantSpeciesUnderSummerWatering.AridLandResearchandManagement28:428‐446.
Munson,S.M.,J.Belnap,C.D.Schelz,M.Moran,andT.W.Carolin.2011.Onthebrinkofchange:plantresponsestoclimate
ontheColoradoPlateau.Ecosphere2:art68.
Parmenter,R.R.2008.Long‐TermEffectsofaSummerFireonDesertGrasslandPlantDemographicsinNewMexico.
RangelandEcologyandManagement61:156–168.
Simonin,K.A.2001.Atriplexconfertifolia.In:FireEffectsInformationSystem,[Online].U.S.DepartmentofAgriculture,
ForestService,RockyMountainResearchStation,FireSciencesLaboratory(Producer).Available:
http://www.fs.fed.us/database/feis/
West,N.E.1983.Intermountainsaltdesertshrublands.Pages375‐397in:N.E.West,editor.Temperatedesertsandsemi‐
deserts.Ecosystemsoftheworld,Volume5.ElsevierPublishingCompany,Amsterdam.
West,N.E.1994.Effectsoffireonsalt‐desertshrubrangelands.InMonsen,S.B.,S.G.Kitchen,comps.1994.Proceedings‐
ecologyandmanagementofannualrangelands;1992May18‐21;Boise,ID.Gen.Tech.RepINT‐GTR‐313.Ogden,UT:U.S.
DepartmentofAgriculture,ForestService,IntermountainResearchStation.416p.

ClimateChangeVulnerabilityAssessmentforColoradoBLM91
OAK & MIXED MOUNTAIN SHRUB
ShrublandsdominatedbyGambeloakorserviceberryandothermontaneshrubspecies
S.Kettler
extentexaggeratedfordisplay
Climate Vulnerability Rank: Low
Vulnerability summary
Key Vulnerabilities:Oakshrublandsaremostvulnerabletodroughtandvariabilityoflatefrosts.The
vulnerabilityofothermountainshrubspeciesisnotwellknown.Theabilitytoresproutafterdisturbance
increasesshrubresilience.
Oakandmixedmountainshrublandsarerankedashavinglow
vulnerabilitytotheeffectsofclimatechangebymid‐century.
Primaryfactorscontributingtothisrankingarethewide
ecologicalamplitudeoftheseshrublandsinColorado,andtheir
abilitytowithstandorrecoverfromdisturbancerelatively
quickly,whichoffsetsthelowerlandscapeconditionscoredueto
pastanthropogenicdisturbancelevels.
Distribution
Thislargepatchecosystemoccursinthemountains,plateaus,andfoothillsintheSouthernRocky
MountainsandColoradoPlateauecoregions.Oakandmixedmountainshrublandsarewidespread
inthewesternhalfofColorado,andalongthesouthernstretchofthemountainfront.These
shrublandsaremostcommonlyfoundalongdryfoothillsandlowermountainslopesfrom
approximately6,500to9,500ft(2,000‐2,900m)inelevation,oftensituatedabovepinyon‐juniper
woodlands,andadjacenttoponderosawoodlands.Theremaybeinclusionsofothermesicmontane
92ColoradoNaturalHeritageProgram©2015
shrublandswithGambeloak(Quercusgambelii)absentorasarelativelyminorcomponent.This
ecosystemintergradeswiththelowermontane‐foothillsshrublandsystemandsharesmanyofthe
samesitecharacteristics.
Characteristic species
StandsdominatedbyGambeloakarecommoninthesouthernpartofColorado,butarecompletely
interspersedwithstandsdominatedbyothershrubspecies,especiallyserviceberry(Amelanchier
spp.)andmahogany(Cercocarpusspp.)athigherelevations.Thevegetationistypicallydominated
byGambeloakaloneorcodominantwithSaskatoonserviceberry(Amelanchieralnifolia),Utah
serviceberry(Amelanchierutahensis),bigsagegrush(Artemisiatridentata),mountainmahogany
(Cercocarpusmontanus),chokecherry(Prunusvirginiana),Stansburycliffrose(Purshia
stansburiana),antelopebitterbrush(Purshiatridentata),mountainsnowberry(Symphoricarpos
oreophilus),orroundleafsnowberry(Symphoricarposrotundifolius).Vegetationtypesinthissystem
mayoccurassparsetodenseshrublandscomposedofmoderatetotallshrubs.Occurrencesmaybe
multi‐layered,withsomeshortshrubbyspeciesoccurringintheunderstoryofthedominant
overstoryspecies.Occurrencescanrangefromdensethicketswithlittleunderstorytorelatively
mesicmixed‐shrublandswitharichunderstoryofshrubs,grassesandforbs.Theseshrubsoften
haveapatchydistributionwithgrassgrowinginbetween.Scatteredtreesareoccasionallypresent
instandsandtypicallyincludespeciesofpineorjuniper.Annualgrassesandforbsareseasonally
present,andweedyannualsareoftenpresent,atleastseasonally.
Non‐oakdominatedmontaneshrublandsareofvariablespeciescomposition,dependingonsite
conditionssuchaselevation,slope,aspect,soiltype,moistureavailability,andpasthistory.Species
presentmayincludemountainmahogany(Cercocarpusmontanus),skunkbushsumac(Rhus
trilobata),clifffendlerbush(Fendlerarupicola),antelopebitterbrush(Purshiatridentata),wildcrab
apple(Peraphyllumramosissimum),snowberry(Symphoricarposspp.),andserviceberry
(Amelanchierspp.).Mostofthesespeciesreproducebothvegetativelyandbyseedlingrecruitment,
aswellasresproutingeasilyafterfire.Variabledisturbancepatternsmayaccountforthelocal
dominanceofaparticularspecies(Keeley2000).Althoughfireisanobvioussourceofdisturbance
intheseshrublands,snowpackmovements(creep,glide,andslippage)mayalsoprovidesignificant
disturbanceinslide‐proneareas(Jamiesonetal.1996).
Spottedtowhee,Virginiawarblers,Green‐tailedtowhee,Blue‐graygnatcatcher,Turkey,blackbear,
deer,elk,andmountainlionarecharacteristicoftheseshrublands.
Environment
Thisecosystemtypicallyoccupiesthelowerslopepositionsofthefoothillandlowermontanezones
whereitmayoccuronleveltosteepslopes,cliffs,escarpments,rimrockslopes,rockyoutcrops,and
screeslopes.Climateissemi‐aridandcharacterizedbymostlyhot‐drysummerswithmildtocold
wintersandannualprecipitationof10‐27in(25‐70cm).Mostprecipitationoccursaswintersnow
butlatesummermonsoonalrainmaybesignificantinsouthernstands.Substratesarevariableand
includesoiltypesrangingfromcalcareous,heavy,fine‐grainedloamstosandyloams,gravelly
loams,clayloams,deepalluvialsand,orcoarsegravel.Soilsaretypicallypoorlydeveloped,rockyto
veryrocky,andwell‐drained.Parentmaterialsincludealluvium,colluvium,andresiduumderived
ClimateChangeVulnerabilityAssessmentforColoradoBLM93
fromigneous,metamorphic,orsedimentaryrockssuchasgranite,gneiss,limestone,quartz,
monzonite,rhyolite,sandstone,schist,andshale.
Dynamics
Theseshrublandsarehighlyfiretolerant.Firecausesdie‐backofthedominantshrubspeciesin
someareas,promotesstumpsproutingofthedominantshrubsinotherareas,andcontrolsthe
invasionoftreesintotheshrublandsystem.DensityandcoverofGambeloakandserviceberry
oftenincreaseafterfire.Naturalfirestypicallyresultinasystemwithamosaicofdenseshrub
clustersandopeningsdominatedbyherbaceousspecies.Historicnaturalfirereturnintervalswere
ontheorderof100yearsinMesaVerde(Floydetal.2000);undersuchconditionsoflowfire
frequency,vulnerablenewlysproutedstemsareabletopersistandformdensethickets.
InsectpestsaffectingGambeloakincludethewoodborer(Agrilusquercicola)andtheoakleafroller
(Archipssemiferana).Thewesterntentcaterpillar(Malacosomacalifornicum)isacommon
defoliatorofshrubspecies.Largeoutbreaksoftheseinsectshavehistoricallybeeninfrequentin
Coloradooakandmixedmountainshrublands(USDAForestService2010).
Oakandmixedmountainshrublandsareimportanthabitatforwildlife,especiallymuledeer,
turkey,andblackbear(Jesteretal.2012).Becauseoakisgenerallyunpalatabletocattle,livestock
grazingcanfacilitatetheincreaseofoakcoverattheexpenseofunderstorygrasses(Mandanyand
West1983).Nativemuledeer,however,browseoakandmixedmountainshrubspeciesduring
mostseasons(Kufeldetal.1973).
CCVA Scoring
Exposure‐Sensitivity (Potential Impact) Rank
PercentColoradoacreswithprojectedtemp>max&pptdelta<5%1.8%
InitialExposure‐SensitivityRankLow
PercentColoradoacreswithtemp<=max&pptdelta<5%morethan50%?No(47.0%)
FinalExposure‐SensitivityRankLow
Exposuretotemperaturechange
Underprojectedmid‐centurytemperatures,about2%ofthecurrentrangeofoak‐mixedmountain
shrublandinColoradowouldexperienceannualmeantemperaturesabovethecurrentstatewide
maximum.
Exposuretoprecipitationchange
About49%ofoak‐mixedmountainshrublandinColoradowillbeexposedtoeffectivelydrier
conditionsevenunderunchangedorslightlyincreasedprecipitationprojectedformid‐century.
Sensitivityofecosystemtotemperatureandprecipitation
Ingeneral,theupperandlowerelevationallimitsofGambeloakshrublandarebelievedtobe
controlledbytemperatureandmoisturestress.NeilsonandWullstein(1983)foundthatseedling
94ColoradoNaturalHeritageProgram©2015
mortalitywasprimarilyduetospringfreezing,grazing,orsummerdroughtstress.Atmore
northernlatitudes,thezoneoftolerablecoldstressisfoundatlowerelevations,but,atthesame
time,theareaswheresummermoisturestressistolerableareathigherelevations.Neilsonand
Wullstein(1983)hypothesizethatthenortherndistributionallimitofGambeloakcorrespondsto
thepointwherethesetwoopposingfactorsconverge.Oakshrublandsaretypicallyfoundinareas
withmeanannualtemperaturesbetween45and50F(7‐10C;Harperetal.1985).Athigher,
coolerelevations,acornproductionmaybelimitedbytheshortnessofthegrowingseason,and
mostreproductionislikelytobevegetative(Christensen1949).Warmingtemperaturesmay
increasebothacornproductionandseedlingsurvival.
Althoughoaksaremostlikelytodowellunderclimatechange,droughtsmayreducethefrequency
ofestablishmentthroughseedlingrecruitmentbyreducingseedlingsurvival(Neilsonand
Wullstein1983).Thelargeracorn‐producingstemsalsoappeartobemorevulnerabletodrought
inducedmortality.
Resilience and Adaptive Capacity Rank
OverallScore: 0.85Rank: High
Bioclimaticenvelopeandrange
Averagedcategoryscore:0.76
OakandmixedmountainshrublandsarewidespreadinwesternColorado,andhavearelatively
broadecologicalamplitude.Theseshrublandsarenotconfinedtohighelevations,andarenotatthe
southernedgeoftheirrangeinColorado.Oakandmixedmountainshrublandshavesignificant
presencein52%ofColorado’soverallprecipitationrange,and53%ofthestate’sgrowingdegree
dayrange,resultinginafairlyhighresiliencescoreforthiscategory
Growthformandintrinsicdispersalrate
Score:1
Theshrubgrowthformofthedominantspecies,andabilitytoquicklycolonizenewareasgivethis
ecosystemahighresiliencescoreforthiscategory.Gambeloakreproducesprimarilybysprouting
ofnewstems,especiallyafterdisturbancessuchasbrushcontrol,fire,andgrazing,although
recruitmentfromseedlingsdoesoccur(Brown1958,Harperetal.1985).Theextensiveclonalroot
systemofGambeloakisaprimarycontributortoitsabilitytosurviveduringperiodswhenseedling
establishmentisimpossible.
Vulnerabilitytoincreasedattackbybiologicalstressors
Score:1
Ingeneraloakandmixedmountainshrublandsarenothighlyvulnerabletoincreasedeffectsof
biologicalstressors.Insomeareas,oakstandsarevulnerabletoincreasedprevalenceofinvasive
speciessuchascheatgrass(Bromustectorum)andknapweeds(Centaureaspp.).Livestockgrazing
ClimateChangeVulnerabilityAssessmentforColoradoBLM95
hasdegradedtheunderstorygrasscommunityofsomeoakstands,andcheatgrassandknapweed
havebecomeestablishedinsomeareas.Mixedmountainshrublandsarelessimpactedbyinvasives.
Vulnerabilitytoincreasedfrequencyorintensityofextremeevents
Score:1
Theseshrublandsarehighlyfiretolerant.Itispossibleforthissystemtomoveupinelevation,
especiallyiffiresopenupsomeoftheadjacentforestedecosystems.
Otherindirecteffectsofnon‐climatestressors–landscapecondition
Score:4.9
OakandmixedmountainshrublandlandscapesinColoradohavebeenmoderatelyimpactedby
anthropogenicactivities.Ongoingbutlimitedthreatsfromurban,exurban,commercial,andenergy
developmentareprimarilyinthesouthernandwesternportionsofColorado,wheretowns,roads,
andutilitycorridorsareoftenincloseproximitytooakshrublands.Mixedmountainshrublandsare
somewhatlessimpactedbydevelopments,primarilythoseassociatedwithrecreationareasor
exurbanhousing.Fireisasourceofdisturbanceintheseshrublands,andtheyarehighlyfire
tolerant.Aswithotherhabitatsinthewildland‐urbaninterface,areasneardevelopedareasare
mostlikelytobethreatenedbytheeffectsoffiresuppression,whilemoreremoteareasare
generallyingoodcondition.
Literature Cited
Brown,H.E.1958.Gambeloakinwest‐centralColorado.Ecology39:317‐327.
Christensen,E.M.1949.Theecologyandgeographicdistributionofoakbrush(Quercusgambelii)inUtah.Thesis.70p.
UniversityofUtah,SaltLakeCity,UT.
Floyd,M.L.,W.H.Romme,andD.D.Hanna.2000.FirehistoryandvegetationpatterninMesaVerdeNationalPark,
Colorado,USA.EcologicalApplications10:1666‐1680.
Harper,K.T.,F.J.Wagstaff,andL.M.Kunzler.1985.BiologymanagementoftheGambeloakvegetativetype:aliterature
review.Gen.Tech.Rep.INT‐179.Ogden,UT:U.S.DepartmentofAgriculture,ForestService,IntermountainForestand
RangeExperimentStation.31p.
Jamieson,D.W.,W.H.Romme,andP.Somers.1996.Bioticcommunitiesofthecoolmountains.Chapter12inTheWestern
SanJuanMountains:TheirGeology,Ecology,andHumanHistory,R.Blair,ed.UniversityPressofColorado,Niwot,CO.
Jester,N.,K.Rogers,andF.C.Dennis.2012.Gambeloakmanagement.NaturalResourcesSeries‐ForestryFactSheetNo.
6.311.ColoradoStateUniversityExtension,FortCollins,Colorado.
Keeley,J.E.2000.Chaparral.Chapter6inNorthAmericanTerrestrialVegetation,secondedition.M.G.BarbourandW.D.
Billings,eds.CambridgeUniversityPress.
Kufeld,R.C.,O.C.Wallmo,andC.Feddema,.1973.FoodsoftheRockyMountainmuledeer.Res.Pap.RM‐111.FortCollins,
CO:U.S.DepartmentofAgriculture,ForestService,RockyMountainForestandRangeExperimentStation.31p.
Madany,M.H.andN.E.West.1983.Livestockgrazing‐fireregimeinteractionswithinmontaneforestsofZionNational
Park,Utah.Ecology64:661‐667.
96ColoradoNaturalHeritageProgram©2015
Neilson,R.P.andL.H.Wullstein.1983.BiogeographyoftwosouthwestAmericanoaksinrelationtoatmospheric
dynamics.JournalofBiogeography10:275‐297. 
ClimateChangeVulnerabilityAssessmentforColoradoBLM97
SAGEBRUSH
Shrublandandsteppecharacterizedbysagebrush,includingthreesubspeciesofbigsagebrush,
blacksagebrush,Bigelowsage,andlittlesagebrush
R.Rondeau
extentexaggeratedfordisplay
Climate Vulnerability Rank: Low
Vulnerability summary
Key Vulnerabilities:Increaseddroughtintensityand/orfrequencyislikelytoincreasetheimpactsoffire
insagebrushshrublands,aswellasplayaroleinthespreadofinvasivespecies.Thevulnerabilityof
sagebrushshrublandsisexpectedtobevariablebysubspecies.
Sagebrushshrublandsarerankedashavinglowvulnerabilityto
theeffectsofclimatechangebymid‐century.Theprimaryfactor
contributingtothisrankingisthecomparativelylowprojected
exposuretowarmeranddrierfutureconditionsinthepartof
Coloradowherethegreaterportionofthishabitatisfound.The
combinationofthethreebigsagebrushsubspeciesinour
analysiscollectivelygivesthishabitattypeawideecological
amplitude.Underalongertimeframe,theseshrublandsmay
havehighervulnerability,similartotheassessmentofPocewicz
etal.(2014)forsagebrushhabitatsinWyoming.Inparticular,the
degradedconditionofsomeareas,andthevulnerabilityofthis
ecosystemtopotentialincreasesinfirefrequencyandseverity,
couldincreasethevulnerabilitytoclimatechange.
Distribution
Asevaluatedherein,thethreesubspeciesofbigsagebrush(basinbigsagebrush,Artemisia
tridentatassp.tridentata,mountainbigsagebrush,A.tridentatassp.vaseyana,andWyomingbig
98ColoradoNaturalHeritageProgram©2015
sagebrush,A.tridentatassp.wyomingensis)arecombinedasthesagebrushecosystem.Ingeneral,
Wyomingbigsagebrushisfoundindrier,warmerareaswhereprecipitationismorelikelytobein
theformofrain,whilemountainbigsagebrushisfoundathigher,coolerelevationswheresnowis
thedominantformofprecipitation(Howard1999,Johnson2000).Changesintemperatureand
precipitationpatternsmayresultinshiftsintherelativeabundanceanddistributionofthethree
subspecies.
ThismatrixformingecosystemoccursthroughoutthemuchofwesternU.S.InColorado,thelargest
occurrencesareinthewesternhalfofthestate,butthissystemcanalsobefoundineastern
Colorado.NorthwesternColorado,NorthPark,MiddlePark,andtheupperGunnisonBasinhave
largeandcontinuousstandsofsagebrushshrublands.
Characteristic species
Sagebrushshrublandsoflower,drierelevationsaredominatedbybasinbigsagebrushand/or
Wyomingbigsagebrush.Additionalshrubspeciespresentmayincludesilversagebrush(Artemisia
cana),rabbitbrush(ChrysothamnusorEricameriaspp.),winterfat(Krascheninnikovialanata),and
antelopebitterbrush(Purshiatridentata).Understoriesaretypicallygrassy,andcommon
graminoidspeciesincludeIndianricegrass(Achnatherumhymenoides),bluegrama(Bouteloua
gracilis),Geyer’ssedge(Carexgeyeri),thickspikewheatgrass(Elymuslanceolatus),Idahofescue
(Festucaidahoensis),Thurberfescue(F.thurberi),needle‐and‐thread(Hesperostipacomata),basin
wildrye(Leymuscinereus),westernwheatgrass(Pascopyrumsmithii),James’galleta(Pleuraphis
jamesii),Sandbergbluegrass(Poasecunda),orbluebunchwheatgrass(Pseudoroegneriaspicata).
Perennialforbspeciestypicallycontributelessthan25%vegetativecover.
Montanesagebrushshrublandorsteppeischaracterizedbymountainbigsagebrush,andavariety
ofothershrubsincludingSaskatoonserviceberry(Amelanchieralnifolia),littlesagebrush
(Artemisiaarbuscula),prairiesagewort(Artemisiafrigida),rubberrabbitbrush(Ericameria
nauseosa),yellowrabbitbrush(Chrysothamnusviscidiflorus),mountainsnowberry(Symphoricarpos
oreophilus),antelopebitterbrush,waxcurrant(Ribescereum),andWoods’rose(Rosawoodsii),may
bepresent.Bothforbsandgrassesaretypicallywellrepresentedintheunderstory.Common
graminoidsincludeIdahofescue,Thurberfescue,timberoatgrass(Danthoniaintermedia),Parry’s
oatgrass(Danthoniaparryi),squirreltail(Elymuselymoides),slenderwheatgrass(Elymus
trachycaulus),spikefescue(Leucopoakingii),westernwheatgrass,bluebunchwheatgrass,
muttongrass(Poafendleriana),Sandbergbluegrassanduplandsedges(Carexspp.).Forbspecies
mayincludecommonyarrow(Achilleamillefolium),rosypussytoes(Antennariarosea),white
sagebrush(Artemisialudoviciana),milkvetch(Astragalusspp.),arrowleafbalsamroot
(Balsamorhizasagittata),Indianpaintbrush(Castillejaspp.),fleabane(Erigeronspp.),buckwheat
(Eriogonumspp.),strawberry(Fragariavirginiana),avens(Geumspp.),owl's‐claws(Hymenoxys
hoopesii),lupine(Lupinus,spp.),phlox(Phloxspp.),andcinquefoil(Potentillaspp.).
Sage‐grouse(Centrocercusspp.)isanindicatorofahealthysagebrushshrubland.
ClimateChangeVulnerabilityAssessmentforColoradoBLM99
Environment
Bigsagebrushshrublandsaretypicallyfoundinbroadbasinsbetweenmountainranges,onplains
andfoothills.Sitesaretypicallyflattorollinghillswithdeep,well‐drainedsandyorloamsoils
between7,000to10,000feetinelevation.Mostannualprecipitationfallsassnowinwinter.
Temperaturesexhibitlargeannualanddiurnalvariation.
Dynamics
Althoughsagebrushtoleratesdryconditionsandfairlycooltemperaturesitisnotfireadapted,and
islikelytobeseverelyimpactedbyintensefiresthatenhancewinderosionandeliminatetheseed
bank(Schlaepferetal.2014).Increasedfirefrequencyandseverityintheseshrublandscouldresult
increasingareadominatedbyexoticgrasses,especiallycheatgrass(Bromustectorum)(D’Antonio
andVitousek1992,ShinnemanandBaker2009).Warmer,driersites(typicallyfoundatlower
elevations)aremoreinvasiblebycheatgrass(Chambersetal.2007).Thereisamoderatepotential
forinvasionbyknapweedspecies,oxeyedaisy,leafyspurge,andyellowtoadflaxunderchanging
climaticconditions,andapotentialforchangingfiredynamicstoaffecttheecosystem.Thereisno
informationonthevulnerabilityofthisecosysteminColoradotoinsectordiseaseoutbreak,
althoughsevereoutbreaksofthesagebrush‐defoliatingmothArogawebsterihavebeenrecorded
furtherwestintheGreatBasin(Bentzetal.2008).Grazingbylargeungulates(bothwildlifeand
domesticlivestock)canchangethestructureandnutrientcyclingofsagebrushshrublands(Manier
andHobbs2007),buttheinteractionofgrazingwithotherdisturbancessuchasfireandinvasive
speciesunderchangingclimaticconditionsappearscomplex(e.g.Daviesetal.2009)andnotwell
studiedinColorado.
CCVA Scoring
Exposure‐Sensitivity (Potential Impact) Rank
PercentColoradoacreswithprojectedtemp>max&pptdelta<5%3.7%
InitialExposure‐SensitivityRankLow
PercentColoradoacreswithtemp<=max&pptdelta<5%morethan50%?No(22.1%)
FinalExposure‐SensitivityRankLow
Exposuretotemperaturechange
Underprojectedmid‐centurytemperatures,about5%ofthecurrentrangeofsagebrushshrubland
inColoradowouldexperienceannualmeantemperaturesabovethecurrentstatewidemaximum.
Exposuretoprecipitationchange
About26%ofsagebrushshrublandinColoradowillbeexposedtoeffectivelydrierconditionseven
underunchangedorslightlyincreasedprecipitationprojectedformid‐century.
Sensitivityofecosystemtotemperatureandprecipitation
Bradley(2010)pointsoutthatsagebrushshrublandsinthewesternU.S.arecurrentlyfoundacross
awidelatitudinalgradient(fromabout35to48degreesnorthlatitude),whichsuggestsadaptation
toacorrespondinglywiderangeoftemperatureconditions.However,becausetheseshrublandsare
100ColoradoNaturalHeritageProgram©2015
apparentlyabletodominateazoneofprecipitationbetweendriersaltbushshrublandsandhigher,
somewhatmoremesicpinyon‐juniperwoodland,thedistributionofsagebrushshrublandsislikely
tobeaffectedbychangesinprecipitationpatterns(Bradley2010).Seasonaltimingofprecipitation
isimportantforsagebrushhabitats;summermoisturestressmaybelimitingifwinterprecipitation
islow(GerminoandReinhardt2014).Seedlingsofmountainbigsagebrusharemoresensitiveto
freezingunderreducedsoilmoistureconditions(Lambrechtetal.2007).Wintersnowpackis
criticalforsagebrushgrowth;lowerelevationsareprobablymoreatriskfromtemperatureimpacts
incomparisontoupperelevationsduetolesssnow,andconsequentlygreaterwaterstress.
Underexperimentalwarmingconditionsinahigh‐elevationpopulation,mountainbigsagebrush
hadincreasedgrowth,suggestingthatlongergrowingseasonlengthcouldfacilitatetheexpansion
ofsagebrushhabitatintoareasthatwereformerlytoocoldfortheshrub(Perforsetal.2003).
However,Pooreetal.(2009)foundthathighsummertemperaturesresultedinlowergrowthrate,
duetoincreasedwaterstress.
Schlaepferetal.(2012)modeledfuturedistributionofthebigsagebrushecosysteminthewestern
U.S.Overtheentirestudyarea,sagebrushdistributionwaspredictedtodecrease,especiallyunder
higherCO2emissionsscenarios.Thestrongestdecreasesareinthesouthernpartoftherange
(includingsouthwesternColorado),whilethedistributionispredictedtoincreaseathigher
elevationsandinareasfartothenorthofColorado.
Resilience and Adaptive Capacity Rank
OverallScore: 0.61Rank: Moderate
Bioclimaticenvelopeandrange
Averagedcategoryscore:0.83
Theseshrublandsareprimarilyfoundinthewesternpartofthestate,atelevationsfromabout
5,000to9,500ft,andarenotrestrictedtohighelevations.TheNorthAmericandistributionof
sagebrushhabitatislargelytothewestandnorthofColorado.Thethreesubspeciesofbig
sagebrushshowanelevationalseparation,withmountainbigsagebrushinwetter,cooler
conditionsofhigherelevations,andWyomingbigsagebrushinthewarmestanddriestconditions
atlowerelevations(Howard1999).Duetotheadaptationsofthevarioussubspecies,therangeof
annualaverageprecipitationforsagebrushhabitatsisfairlywide,fromabout8‐40in(20‐100cm),
withameanof18in(45cm),covering64%ofthestatewideprecipitationrange.Growingseason
heataccumulationisalsohighlyvariableacrosstherangeofthehabitat,forthesamereason,and
covers67%ofthestatewiderange.Thiscombinationoffactorsgivessagebrushshrublandsahigh
resiliencescoreinthiscategory.
Growthformandintrinsicdispersalrate
Score:0.5
Sagebrushreceivedanintermediateresiliencescoreduetoitsgenerallyslowergrowthratesand
inabilitytoresproutafterfire.Sagebrushisgenerallyapoorseeder,withsmalldispersaldistances,
ClimateChangeVulnerabilityAssessmentforColoradoBLM101
however,therearenoapparentbarrierstodispersalfortheseshrublands.Thesestandsmayalso
besomewhatvulnerabletochangesinphenology.
Vulnerabilitytoincreasedattackbybiologicalstressors
Score:0.7
Otherstressorsforsagebrushshrublandsareinvasionbycheatgrassandexpansionofpinyon‐
juniperwoodlands.Thereisamoderatepotentialforinvasionbyknapweedspecies,oxeyedaisy,
leafyspurge,andyellowtoadflaxunderchangingclimaticconditions,andapotentialforchanging
firedynamicstoaffecttheecosystem.Thereisnoinformationonthevulnerabilityofthisecosystem
toinsectordiseaseoutbreak.
Grazingbylargeungulates(bothwildlifeanddomesticlivestock)canchangethestructureand
nutrientcyclingofsagebrushshrublands(ManierandHobbs2007),buttheinteractionofgrazing
withotherdisturbancessuchasfireandinvasivespeciesunderchangingclimaticconditions
appearscomplex(e.g.Daviesetal.2009)andnotwellstudiedinColorado.
Vulnerabilitytoincreasedfrequencyorintensityofextremeevents
Score:0.5
Althoughsagebrushtoleratesdryconditionsandfairlycooltemperaturesitisnotfireadapted,and
noneofthesubspeciesresproutafterfire(Tirmenstein1999).Sagebrushshrublandislikelytobe
severelyimpactedbyintensefiresthatenhancewinderosionandeliminatetheseedbank(Young
andEvans1989).Increaseddroughtmayincreasefirefrequencyandseverity,eliminating
sagebrushinsomeareas,especiallyatdriersitesoflowerelevations.Increasedfirefrequencyand
severityintheseshrublandsmayresultintheirconversiontograsslandsdominatedbyexotic
species.
Otherindirecteffectsofnon‐climatestressors–landscapecondition
Score:0.53
SagebrushshrublandlandscapesinColoradohavebeenmoderatelyimpactedbyanthropogenic
disturbance.Threatstosagebrushshrublandsfromexurbanorrecreationalareadevelopmentare
limited,butongoingataverylowlevel.Huntingandrecreationareminorsourcesofdisturbancein
thishabitat.Chainingorothershrubremovalformownhay,andtoalesserextentconversionto
croplandisasubstantialthreatinnorthwesternColorado.Largecoalminingoperationsthat
completelyremovethishabitatpriortoreclamationactivityareanongoingthreattothe
connectivityandqualityoftheseshrublands.Oilandgasdevelopment,withassociatedroads,
pipelinecorridors,andinfrastructureisanotherongoingsourceofanthropogenicdisturbance,
fragmentation,andlossinthishabitatinnorthwesternColorado.
Literature Cited
Bentz,B.,D.Alston,andT.Evans.2008.GreatBasininsectoutbreaks.In:Chambers,J.C.,N.Devoe,andA.Evenden,eds.
CollaborativemanagementandresearchintheGreatBasin‐examiningtheissuesanddevelopingaframeworkforaction.
102ColoradoNaturalHeritageProgram©2015
Gen.Tech.Rep.RMRS‐GTR‐204.FortCollins,CO:U.S.DepartmentofAgriculture,ForestService,RockyMountainResearch
Station.p.45‐48.
Bradley,B.A.2010.Assessingecosystemthreatsfromglobalandregionalchange:hierarchicalmodelingofriskto
sagebrushecosystemsfromclimatechange,landuseandinvasivespeciesinNevada,USA.Ecography33:198‐208.
Chambers,J.C.,B.A.Roundy,R.R.Blank,S.E.Meyer,andA.Whittaker.2007.WhatmakesGreatBasinsagebrush
ecosystemsinvasiblebyBromustectorum?EcologicalMonographs77:117‐145.
D’Antonio,C.M.andP.M.Vitousek.1992.Biologicalinvasionsbyexoticgrasses,thegrass/firecycle,andglobalchange.
AnnualReviewofEcologyandSystematics23:63–87.
Davies,K.E.,T.J.Sevjcar,andJ.D.Bates.2009.Interactionofhistoricalandnonhistoricaldisturbancesmaintainsnative
plantcommunities.EcologicalApplications19:1536‐1545.
Germino,M.J.andK.Reinhardt.2014.Desertshrubresponsestoexperimentalmodificationofprecipitationseasonality
andsoildepth:relationshiptothetwo‐layerhypothesisandecohydrologicalniche.JournalofEcology102:989‐997.
Howard,J.L.1999.Artemisiatridentatasubsp.wyomingensis.In:FireEffectsInformationSystem,[Online].U.S.
DepartmentofAgriculture,ForestService,RockyMountainResearchStation,FireSciencesLaboratory(Producer).
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Johnson,K.A.2000.Artemisiatridentatasubsp.vaseyana.In:FireEffectsInformationSystem,[Online].U.S.Departmentof
Agriculture,ForestService,RockyMountainResearchStation,FireSciencesLaboratory(Producer).Available:
http://www.fs.fed.us/database/feis/
Lambrecht,S.C.,A.K.Shattuck,andM.E.Loik.2007.Combineddroughtandepisodicfreezingonseedlingsoflow‐and
high‐elevationsubspeciesofsagebrush(Artemisiatridentata).PhysiologiaPlantarum130:207‐217.
Manier,D.J.andN.T.Hobbs.2007.Largeherbivoresinsagebrushsteppeecosystems:livestockandwildungulates
influencestructureandfunction.Oecologia152:739‐750.
Perfors,T.,J.Harte,andS.E.Alter.2003.Enhancedgrowthofsagebrush(Artemisiatridentata)inresponsetomanipulated
ecosystemwarming.GlobalChangeBiology9:736‐742.
Pocewicz,A.,H.E.Copeland,M.B.Grenier,D.A.Keinath,andL.M.Washkoviak.2014.Assessingthefuturevulnerabilityof
Wyoming’sterrestrialwildlifespeciesandhabitats.ReportpreparedbyTheNatureConservancy,WyomingGameand
FishDepartmentandWyomingNaturalDiversityDatabase.
Poore,R.E.,C.A.Lamanna,J.J.Ebersole,andB.J.Enquist.2009.Controlsonradialgrowthofmountainbigsagebrushand
implicationsforclimatechange.WesternNorthAmericanNaturalist69:556‐562.
Schlaepfer,D.R.,W.K.Lauenroth,andJ.B.Bradford.2012.Effectsofecohydrologicalvariablesoncurrentandfuture
ranges,localsuitabilitypatterns,andmodelaccuracyinbigsagebrush.Ecography35:374‐384.
Shinneman,D.J.andW.L.Baker.2009.Environmentalandclimaticvariablesaspotentialdriversofpost‐firecoverof
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18:191‐202.
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ofAgriculture,ForestService,RockyMountainResearchStation,FireSciencesLaboratory(Producer).Available:
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Young,J.A.andR.A.Evans.1989.Dispersalandgerminationofbigsagebrush(Artemisiatridentata)seeds.WeedScience
37:201‐206. 
ClimateChangeVulnerabilityAssessmentforColoradoBLM103
SANDSAGE
Shrublandorsteppecharacterizedbysandsagebrush
S.Kettler
extentexaggeratedfordisplay
Climate Vulnerability Rank: Moderate
Vulnerability summary
Key Vulnerabilities:Extendedperiodsofdroughtthatdecreaselevelsofvegetationcoverwould
increasethelikelihoodthatsandysubstrateswillbemobilized.Thelossofnativeplantbiodiversityin
manystandsdecreasestheavailableassemblageofdrought‐adaptedspeciesthatcanboostresilienceto
thisvulnerability.
Sandsageshrublandsarerankedmoderatelyvulnerabletothe
effectsofclimatechangebymid‐century.Thisrankingis
primarilyduetotheconcentrationofgreatestexposureforall
temperaturevariablesontheeasternplainsofColorado,where
thisecosystemisfound.Inaddition,anthropogenicdisturbance
intheseshrublandshasreducedtheoveralllandscapecondition
ofthehabitat.Theseshrublandsarewelladaptedtosandysoils,
andmaybeabletoexpandintoadjacentareasunderwarmer,
drierconditions,dependingondisturbanceinteractions.Overall
conditionandcompositionoftheseshrublandsmaychangewith
changingclimate.
Distribution
Thesandsageecosystemisfoundprimarilyinthesouth‐centralareasoftheWesternGreatPlains.
OccurrencesgenerallyrangefromtheNebraskaSandhillregionsouthtocentralTexas,although
someexamplesmaybefoundasfarnorthastheBadlandsofSouthDakota.Thegreaterpartofthe
ecosystemoccursintheCentralShortgrassPrairieecoregionineasternColorado,westernKansas
104ColoradoNaturalHeritageProgram©2015
andsouthwesternNebraska.SandsageshrublanddominatessandysoilsofColorado’seastern
plains,atelevationsgenerallybelow5,500ft.
Theseshrublandshaveoftenbeentreatedasanedaphicvariantofeasternplainsmixed‐grass
prairie(Albertson&Weaver1944,Daley1972),orofshortgrassprairie(Ramaley1939,Simsand
Risser2000).Sandsage(Artemisiafilifolia)formsextensiveopenshrublandsinsandysoilsof
Colorado’seasternplains,andisofparticularimportanceforbothgreaterandlesserprairie
chickenhabitat,aswellasforothergrasslandbirds.IneasternColorado,thissystemisfoundin
extensivetractsonQuaternaryeoliandepositsalongtheSouthPlatte,ArikareeandRepublican
Rivers,betweenBigSandyandRushCreeks,andalongtheArkansasandCimarronRivers,whereit
iscontiguouswithareasinKansasandOklahoma(Comeretal.2003).
Characteristic species
Throughoutitsrange,thissystemischaracterizedbyasparsetomoderatelydensewoodylayer
dominatedbysandsage.Theseshrubsusuallydonotgrowasclumpsbutratherasindividuals,and
theinterveninggroundismostoftendominatedbyasparsetomoderatelydenselayeroftall,mid‐
orshortgrasses.Associatedspeciescanvarywithgeography,precipitation,disturbanceandsoil
texture.Graminoidspeciessuchassandbluestem(Andropogonhallii),threeawn(Aristidaspp.),
grama(Boutelouaspp.),prairiesandreed(Calamovilfalongifolia),needle‐and‐thread(Hesperostipa
comata),andsanddropseed(Sporoboluscryptandrus)aretypical.Othershrubspeciesmayalsobe
presentincludingtreecholla(Cylindropuntiaimbricata),broomsnakeweed(Gutierreziasarothrae),
pricklypear(Opuntiaspp.),westernsandcherry(Prunuspumilavar.besseyi),andsoapweedyucca
(Yuccaglauca).
Greaterandlesserprairie‐chickens,Cassin’ssparrows,andornateboxturtlesareindicatorsofa
healthysandsageprairiesystem.
Environment
Throughoutitsrangeitiscloselytiedtosandysoils,andthisedaphicrestrictionischaracteristicof
largepatchsystems.Littleisknownaboutthetoleranceofsandsageforsoilsotherthanwell‐
drainedsandwithalowsiltandclaycomponent.Suchsoilsareoften“droughty”,withreduced
water‐holdingability,andconsequently,thepotentialforincreasedwaterstresstoresidentplants
(SoilSurveyDivisionStaff1993).RasmussenandBrotherson(1984)speculatedthatsandsageis
adaptedtolessfertilesoilsthanspeciesofadjacentgrasslandcommunities.
Dynamics
Ramaley(1939)indicatedthatthepersistenceofsandsagewasfacilitatedbyfireandlong
overgrazing,intheabsenceofwhichasitewouldtransitiontosandprairie.However,thereisno
evidencetosuggestthat,undercertaincombinationsoftemperature,precipitation,grazing,and
otherdisturbance,sandsagewouldbeunabletoexpandontoothersoiltypes.Firesuppressionmay
alsocontributetoanincreaseinshrubdensityinthishabitat,althoughsandsagequicklyresprouts
afterburning.Disturbancefromgrazing,fire,anddrought,incombinationwithrangeimprovement
practices,haspermittedtheestablishmentandspreadofnon‐nativespecies.
ClimateChangeVulnerabilityAssessmentforColoradoBLM105
Colorado’seasternplainsexhibitclimaticdifferencesfromnorthtosouthwhichmaybereflectedin
thelocalexpressionofsandsageshrubland.OccurrencesinsouthernColoradoexperiencealonger
growingseason,lowerannualprecipitation,anddifferencesinprecipitationpatterns(Western
RegionalClimateCenter2004),andmaybedominatedbydifferentspeciesthannorthernstands.In
thesouthernrangeofthissystem,Havardoak(Quercushavardii)mayalsobepresentand
representsonesuccessionpathwaythatdevelopsovertimefollowingadisturbance.Havardoakis
abletoresproutfollowingafireandthusmaypersistforlongperiodsoftimeonceestablished
(WrightandBailey1982).
Duringthepast10,000years,theseareasarelikelytohavefluctuatedbetweenactivedunefields
andstabilized,vegetateddunes,dependingonclimateanddisturbancepatterns(Formanetal.
2001).Extendedperiodsofseveredroughtorotherdisturbancethatresultsinlossofstabilizing
vegetationcanquicklyleadtosoilmovementandblowoutsthatinhibitvegetationre‐
establishment,andmayeventuallyleadtodramaticallydifferentspeciescomposition.
CCVA Scoring
Exposure‐Sensitivity (Potential Impact) Rank
PercentColoradoacreswithprojectedtemp>max&pptdelta<5%44.1%
InitialExposure‐SensitivityRankHigh
PercentColoradoacreswithtemp<=max&pptdelta<5%morethan50%?No(21.3%)
FinalExposure‐SensitivityRankHigh
Exposuretotemperaturechange
Underprojectedmid‐centurytemperatures,about50%ofthecurrentrangeofsandsageshrubland
inColoradowouldexperienceannualmeantemperaturesabovethecurrentstatewidemaximum.
Exposuretoprecipitationchange
About65%ofsandsageshrublandinColoradowillbeexposedtoeffectivelydrierconditionseven
underunchangedorslightlyincreasedprecipitationprojectedformid‐century.
Sensitivityofecosystemtotemperatureandprecipitation
Sandsagesharesthedryandwarmclimateofshortgrass.Annualaverageprecipitationisonthe
orderof10‐18inches(25‐47cm),withameanof16in(40cm).Thegrowingseasonisgenerally
long,withfrequenthightemperatures.
SandsageoccurrencesinColoradohavehistoricallyexperiencedseasonaldifferencesin
precipitationpatternsfromnorthtosouth(WesternRegionalClimateCenter2004).North‐south
gradientsintemperatureandprecipitationonColorado’seasternplainsappeartobereflectedin
thespeciescompositionofsandsagehabitat,especiallyinmidgrassspecies(Daley1972),which
maycontributetovariablevulnerabilitybetweennorthernandsouthernstands.
106ColoradoNaturalHeritageProgram©2015
Resilience and Adaptive Capacity Rank:
OverallScore: 0.71Rank: High
Bioclimaticenvelopeandrange
Averagedcategoryscore:0.62
Theseshrublandsarenotlimitedtohighelevations,andinColoradoarewellwithintherangeof
continentaldistribution.Thegeneralrestrictionofsandsageshrublandstowarm,dryareason
Colorado’seasternplainsmeansthattheydisplayasomewhatrestrictedecologicalenvelope,
covering18%ofthestatewideprecipitationrange,and57%ofthegrowingdegreedayrange.The
moderateresiliencescoreforthiscategorymaynotreflectthetruecapacityoftheseshrublandsto
adapttochangingclimateconditionsifsuitablesubstratesareavailable.
Growthformandintrinsicdispersalrate
Score:1
Sandsageisoftenabletoresproutquicklyafterfire,althoughitmayhavepoordispersalability,
withmostseedslandingclosetotheparentplant(McWilliams2003).Theapparentabilityofthis
speciestoestablishquicklyafterdisturbancegivesitahighresiliencescoreinthiscategory.
Vulnerabilitytoincreasedattackbybiologicalstressors
Score:1
Domesticlivestockgrazingtendstofavortheincreaseofsandsageoverassociatednativegrasses.
Long‐termcontinuousgrazingofdomesticlivestockhascontributedtothealterationofthese
shrublandhabitatsfromtheirpre‐settlementcondition,however,thisfactorisgenerallylessofa
threatthanchangesintemperatureandprecipitation.
Vulnerabilitytoincreasedfrequencyorintensityofextremeevents
Score:0.5
Droughtisthemostimportantextremeeventthatislikelytoalterthecharacterofthese
shrublands.Warmeranddrierconditions,andresultingreducedvegetationcovercouldallow
reactivationofcurrentlystabilizedsandysoilsthroughouteasternColorado.Althoughsandsage
doesnotreproducevegetatively,itisabletoresproutafterfire.Fireextentandintensityare
correlatedwithclimateandgrazingeffectsonfuelloads.Fireandgrazingarebothimportant
disturbanceprocessesforsandsagehabitat,andmayinteractwithdrought,aswellaspermitting
invasiveexoticplantspeciestoestablishandspread.
Otherindirecteffectsofnon‐climatestressors–landscapecondition
Score:0.43
SandsagelandscapesinColoradoaresignificantlyimpactedbyanthropogenicactivities.Insome
casesthishasincreasedtheextentofsandsageshrublandifmidgrassprairieisconvertedto
ClimateChangeVulnerabilityAssessmentforColoradoBLM107
shortgrass‐sandsagecommunity,dueinlargeparttolong‐termcontinuousgrazingbydomestic
livestock(LANDFIRE2006).Sandsageshrublandshavelimitedbutongoingthreatofconversionto
tilledagricultureorurban/exurbanandcommercialdevelopment.Oilandgasdevelopment,and
windturbinefarms,withassociatedroads,utilitycorridors,andinfrastructureisaprimaryongoing
sourceofanthropogenicdisturbance,fragmentation,andlossinthishabitat.
Literature Cited
Albertson,F.W.andJ.E.Weaver.1944.NatureanddegreeofrecoveryofgrasslandfromtheGreatDroughtof1933to
1940.EcologicalMonographs14:393‐479.
Comer,P.,S.Menard,M.Tuffly,K.Kindscher,R.Rondeau,G.Jones,G.Steinuaer,andD.Ode.2003.UplandandWetland
EcologicalSystemsinColorado,Wyoming,SouthDakota,Nebraska,andKansas.Reportandmap(10hectareminimum
mapunit)totheNationalGapAnalysisProgram.Dept.ofInteriorUSGS.NatureServe.
Daley,R.H.1972.ThenativesandsagevegetationofeasternColorado.M.S.Thesis,ColoradoStateUniversity,FortCollins,
Colorado.
Forman,S.L.,R.Oblesby,andR.S.Webb.2001.TemporalandspatialpatternsofHoloceneduneactivityontheGreatPlains
ofNorthAmerica:megadroughtsandclimatelinks.GlobalandPlanetaryChange29:1‐29.
LANDFIRE.2006.LANDFIREBiophysicalSettingModels.BiophysicalSetting3310940,WesternGreatPlainsSandhill
Steppe.USDAForestService;U.S.DepartmentofInterior.Availableat:
http://www.landfire.gov/national_veg_models_op2.php
McWilliams,J.2003.ArtemisiafilifoliaIn:FireEffectsInformationSystem,[Online].U.S.DepartmentofAgriculture,Forest
Service,RockyMountainResearchStation,FireSciencesLaboratory(Producer).Available:
http://www.fs.fed.us/database/feis/
Ramaley,F.1939.Sand‐hillvegetationofnortheasternColorado.EcologicalMonographs9(1):1‐51.
Rasmussen,L.L.andJ.D.Brotherson.1986.Habitatrelationshipsofsandsage(Artemisiafilifolia)insouthernUtah.In:
McArthur,E.D.,andB.L.Welch,compilers.Proceedings‐‐symposiumonthebiologyofArtemisiaandChrysothamnus;
1984July9‐13;Provo,UT.Gen.Tech.Rep.INT‐200.Ogden,UT:U.S.DepartmentofAgriculture,ForestService,
IntermountainResearchStation:58‐66.
Sims,P.L.,andP.G.Risser.2000.Grasslands.In:Barbour,M.G.,andW.D.Billings,eds.,NorthAmericanTerrestrial
Vegetation,SecondEdition.CambridgeUniversityPress,NewYork,pp.323‐356.
SoilSurveyDivisionStaff.1993.Soilsurveymanual.SoilConservationService.U.S.DepartmentofAgricultureHandbook
18.Availableat:http://www.nrcs.usda.gov/wps/portal/nrcs/detail/soils/ref/?cid=nrcs142p2_054261
WesternRegionalClimateCenter[WRCC].2004.ClimateofColoradonarrativeandstateclimatedata.Availableat
http://www.wrcc.dri.edu
Wright,H.A.andA.W.Bailey.1982.Fireecology:UnitedStatesandsouthernCanada.JohnWileyandSons.NY.501p.
108ColoradoNaturalHeritageProgram©2015
Grassland or Herbaceous
Table 2.7.Keyvulnerabilities,grasslandorotherherbaceousecosystems.
Habitat Climate factor(s) Consequences Other considerations
AlpineExtendedgrowingseason
withearliersnowmelt
Conversiontoothertype
thatincludesshrubsor
trees
Barrierstodispersal
MontanegrasslandDrought,warmer
temperatures
Woodyspeciesinvasion,
exotics;potentialtoexpand
intoburnedforestareas
Highlyaltered
Semi‐desert
grassland
‐‐‐‐ MayincreasePoorconnectivity
ShortgrassExtendeddrought,warmer
summernighttime
temperatures
Changeinrelativespecies
abundance,woodyspecies
invasion,orconversionto
othertype
Anthropogenicdisturbance
ClimateChangeVulnerabilityAssessmentforColoradoBLM109
ALPINE
Thisecosystemincludeshigh‐elevationdrytundraturf,dwarf‐shrublands,fellfield,androckand
screecommunities.
R.Rondeau
Extentexaggeratedfordisplay
Climate Vulnerability Rank: Low
Vulnerability summary
Key Vulnerabilities:Warmerconditionsleadingtoearliersnowmeltandanextendedgrowingseasonin
higherelevationsareexpectedtoallowtheestablishmentofwoodyspeciesabovecurrenttreeline
levels,althoughthisprocessislikelytobeslow.Photoperiodcues(notinfluencedbyclimatechange)for
manyspeciescouldnegatetheeffectsofalongergrowingseason.Theabilityofmostalpinespeciesto
disperseacrossinterveninglowerelevationhabitatisdoubtful.
Alpinehabitatsarerankedashavinglowvulnerabilitytothe
effectsofclimatechangebymid‐century,duetolimitedexposure
towarmeranddrierconditions.Overall,alpineareasareingood
condition,withmoderateresilience.Becauseoftheshortgrowing
seasonlengthinalpineandsubalpineareas,changeisexpected
tooccurrelativelyslowly.Underalonger‐termevaluationframe,
vulnerabilityofthishabitatisexpectedtobegreater,sincethese
habitatsarerestrictedtothehighestelevationsofColorado,and
consequentlyhaveanarrowbiophysicalenvelope.
Distribution
ThiswidespreadecosystemoccursaboveuppertimberlinethroughouttheRockyMountain
cordillera.Alpinevegetationisfoundatthehighestelevations,usuallyabove11,000feetin
110ColoradoNaturalHeritageProgram©2015
Colorado,wherethelongwinters,abundantsnowfall,highwinds,andshortsummerscreatea
harshenvironment.Althoughalpinedryturfformsthematrixofthealpinezone,itintermingles
withbedrockandscree,icefield,fellfield,alpinedwarf‐shrubland,andalpine/subalpinewet
meadowsystems.Areasdominatedbyherbaceouscovermaybedrytundra,cushion‐plant
dominatedfellfield,orwetmeadows.Shrub‐dominatedareasarecharacterizedby ericaceous
dwarf‐shrubsordwarfwillows.
Characteristic species
Alpinedryturfisformedbyadensecoveroflow‐growing,perennialgraminoidsandforbs.
Rhizomatous,sod‐formingsedgesarethedominantgraminoids,andprostrateandmat‐forming
plantswiththickrootstocksortaprootscharacterizetheforbs.Dominantspeciesincludeboreal
sagebrush(Artemisiaarctica),blackrootsedge(Carexelynoides),spikesedge(Carexnardina),
northernsinglespikesedge(Carexscirpoidea),dryspikesedge(Carexsiccata),curlysedge(Carex
rupestris),tuftedhairgrass(Deschampsiacaespitosa),alpinefescue(Festucabrachyphylla),Idaho
fescue(Festucaidahoensis),Ross'avens(Geumrossii),Bellardibogsedge(Kobresiamyosuroides),
cushionphlox(Phloxpulvinata),andalpineclover(Trifoliumdasyphyllum).Dwarf‐shrublandsof
thealpinearecharacterizedbyanintermittentlayerofsnowwilloworericaceousdwarf‐shrubs
lessthan0.5minheight,withamixtureofforbsandgraminoids,especiallysedges.Snowwillow
(Salixnivalis)isatypicaldominantshrub.Blueberry(Vacciniumspp.)andalpinelaurel(Kalmia
microphylla)mayalsobeshrubassociates.
Mostfellfieldplantsarecushionedormatted,frequentlysucculent,low‐growingrosettesandoften
denselyhairedandthicklycutinized.Plantcovermaybesparsetomoderatebetweenexposed
rocks.CommonfellfieldspeciesincludeRoss'avens,Bellardibogsedge,twinflowersandwort
(Minuartiaobtusiloba),Asianforget‐me‐not(Myosotisasiatica),RockyMountainnailwort
(Paronychiapulvinata),cushionphlox(Phloxpulvinata),creepingsibbaldia(Sibbaldiaprocumbens),
mosscampion(Sileneacaulis),alpinecloverandParry’sclover(Trifoliumparryi).Barrenand
sparselyvegetatedalpinesubstratesincludebothbedrockoutcropandscreeslopes,with
nonvascular(lichen)dominatedcommunities.Therecanbesparsecoverofforbs,grasses,lichens
andlowshrubs.ClumpsofColoradobluecolumbine(Aquilegiacaerulea)andmountainthistle
(Cirsiumscopulorum)arecommoninscreeslopes.
Environment
Thedistributionofvegetationtypesinthealpineiscontrolledinpartbylocaltopographythat
influencessnowdepositionandretention,aswellassoildevelopment.Alpineturfisgenerally
foundonmoregentletomoderateslopes,flatridges,valleys,andbasins,wherethesoilhasbecome
relativelystabilizedandthewatersupplyismoreorlessconstant.Alpinedwarf‐shrublandtypically
isfoundinareasoflevelorconcaveglacialtopography,withlate‐lyingsnowandsub‐irrigation
fromsurroundingslopes.Thesemoistbutwell‐drainedareashavedevelopedrelativelystablesoils
thatarestronglyacidic,oftenwithsubstantialpeatlayers.Fellfieldsarerockyandwind‐scoured
areasthatarefreeofsnowinthewinter,suchasridgetopsandexposedsaddles,wherevegetation
isexposedtosevereenvironmentalstress.Soilsonthesewindysitesareshallow,stony,lowin
organicmatter,andpoorlydeveloped;winddeflationoftenresultsinagravellypavement.
ClimateChangeVulnerabilityAssessmentforColoradoBLM111
Thereissomeevidencethatalpinevegetationisresponsivetofine‐scaleenvironmental
heterogeneity,whichmayenhanceitsresiliencetochangingclimateconditionsinsome
topographicallycomplexareas(Spasojevicetal.2013).
Dynamics
Alpineenvironmentsaregenerallynotsusceptibletooutbreaksofpestspeciesordisease,butmay
havesomeslightvulnerabilitytoinvasiveplantspeciessuchasyellowtoadflax(Linariavulgaris),
knapweed(Centaureaspp.),anddandelion(Taraxacumofficinale).Thesetreelessenvironmentsare
notvulnerabletofire,butcouldbecomesoiftreesareabletoestablish.
Patternsofvegetationgrowth,flowering,andsenescenceinalpinehabitatsareprobablydependent
onbothdaylengthandtemperature(BillingsandMooney1968).Thecharacteristicforband
graminoiddominatedtundraisaresultoflowtemperaturesduringthegrowingseasonthatlimit
vegetationgrowthanddecomposition.Withlongerdaylengthandincreasingsolarradiationin
spring,warmerairandsoiltemperatures,togetherwithmoisturefromsnowmeltenabletheonset
ofplantgrowth.Althoughtemperatureappearstobethedominantcontrolondevelopmental
phenology(BillingsandMooney1968),anumberofalpinespeciesareknowntobesensitiveto
day‐length(KellerandKörner2003).Theprevalenceandimportanceofphotoperiodsensitivityin
Colorado’salpinefloraislittleknown.Ifsomealpinespeciesareunabletoquicklyadaptto
changingtemperaturesbecauseofphotoperiodconstraints,thiscouldchangespeciesinteractions
andrelativeabundancesinalpinehabitats,withconsequencesthatarenotwellunderstood(Hülber
etal.2010,Ernakovichetal.2014).
CCVA Scoring
Exposure‐Sensitivity (Potential Impact) Rank
PercentColoradoacreswithprojectedtemp>max&pptdelta<5%0%
InitialExposure‐SensitivityRankLow
PercentColoradoacreswithtemp<=max&pptdelta<5%morethan50%?No(38.9%)
FinalExposure‐SensitivityRankLow
Exposuretotemperaturechange
Underprojectedmid‐centurytemperatures,lessthan1%ofthecurrentrangeofalpinehabitatin
Coloradowouldexperienceannualmeantemperaturesabovethecurrentstatewidemaximum.
Exposuretoprecipitationchange
About39%ofalpinehabitatinColoradowillbeexposedtoeffectivelydrierconditionsevenunder
unchangedorslightlyincreasedprecipitationprojectedformid‐century.
Sensitivityofecosystemtotemperatureandprecipitation
Snowpackisacrucialcomponentofalpineecosystems,anddependsonbothprecipitationamounts
andwinter‐springtemperature(Williamsetal.2002).Vegetationinalpineareasiscontrolledby
112ColoradoNaturalHeritageProgram©2015
patternsofsnowretention,winddesiccation,permafrost,andashortgrowingseason(Greenland
andLosleben2001).
Thelengthofthegrowingseasonisparticularlyimportantforthealpinezone,andforthetransition
zonebetweenalpineandforest(treeline).Alpineareashavethefewestgrowingdegreedaysand
lowestpotentialevapotranspirationofanyhabitatinColorado.Treeline‐controllingfactorsoperate
atdifferentscales,rangingfromthemicrositetothecontinental(HoltmeierandBroll2005).Ona
globalorcontinentalscale,thereisgeneralagreementthatcoolsummertemperatureisaprimary
determinantoftreeline.Atthisscale,thedistributionofalpineecosystemsisdeterminedbythe
numberofdaysthatarewarmenoughforalpineplantgrowth,butnotsufficientfortreegrowth.
Otheralpineconditionsthatmaintaintreelessvegetationathighelevationsincludelackofsoil
development,persistentsnowpack,steepslopes,wind,anddenseturfthatrestrictstreeseedling
establishmentandsurvivalwithinthetreelineecotone(Moiretal.2003,Smithetal.2003,
HoltmeierandBroll2005).However,increasedextentoftallshrubwillows(e.g.,Salixplanifoliaand
S.glauca)throughclonalgrowthhasalreadyoccurredinsomeareas(Formicaetal.2014).
Onthebasisofhistoricevidence,treelineisgenerallyexpectedtomigratetohigherelevationsas
temperatureswarm,aspermittedbylocalmicrositeconditions(Smithetal.2003,Richardsonand
Friedland2009,Grafiusetal.2012).Itisunlikelythatalpinespecieswouldbeabletomovetoother
alpineareas.Intheshort‐termwithwarmertemperatures,alpineareasmaybeabletopersist,
especiallyinareaswhereitisdifficultfortreestoadvanceupslope.Theslowgrowthofwoody
speciesandrarityofrecruitmenteventsmaydelaytheconversionofalpineareastoforestortall
shrubfor50‐100+afterclimaticconditionshavebecomesuitablefortreegrowth(Körner2012).
Thus,alpineecosystemsmaypersistforawhilebeyondmid‐century,butarelikelytoeventually
largelydisappearfromColorado.
Resilience and Adaptive Capacity Rank:
OverallScore: 0.69Rank: Moderate
Bioclimaticenvelopeandrange
Averagedcategoryscore:0.25
ElevationsofalpinehabitatsinColoradorangefromabout11,000toover14,000ft.,withameanof
about12,000ft.Alpinehabitatsarerestrictedtohighelevations,andarealsonearthesouthern
extentoftheircontinentalrangeinColorado.Althoughalpineareascover74%ofthestatewide
precipitationrange,alpinegrowingseasonsaretheshortestofanyhabitatinColorado,
encompassingonly26%ofthestatewiderangeofgrowingdegreedays.Thesefactorscombineto
givealpineareasalowresiliencescoreinthiscategory.
Growthformandintrinsicdispersalrate
Score:0.50
ClimateChangeVulnerabilityAssessmentforColoradoBLM113
Althoughalpineareasaredominatedbyrelativelyquick‐growingforbandgraminoidspecies,the
shortgrowingseasonsarelimiting.Furthermore,thedifficultyofdispersalacrossintervening
lowerelevationhabitatgivesthisecosystemanintermediateresiliencescoreinthiscategory.
Vulnerabilitytoincreasedattackbybiologicalstressors
Score:0.8
Alpineenvironmentsaregenerallynotsusceptibletooutbreaksofpestspeciesordisease,butmay
havesomeslightvulnerabilitytoinvasiveplantspeciessuchasyellowtoadflaxunderfuture
climaticconditions.Thesetreelessenvironmentsarenotvulnerabletofire,butcouldbecomesoif
treesareabletoestablish.Xericalpineenvironmentsarealreadysubjecttoextremeconditions,but
themoremesicareasarevulnerabletodroughtandchangesinsnowmelttiming.Evenunder
increasedsnowpack,warmertemperaturesarelikelytoalterpatternsofsnowmelt,andmay
reduceavailablemoisture.Thesechangesarelikelytoresultinshiftsinspeciescomposition,
perhapswithanincreaseinshrubsonxerictundra.Withwarmingtemperaturesandearlier
snowmelt,however,elkmaybeabletomoveintoalpineareasearlierandstaylonger,thereby
increasingstressonalpinewillowcommunities(Zeigenfussetal.2011).
Vulnerabilitytoincreasedfrequencyorintensityofextremeevents
Score:0.9
Alpinehabitatsarealsoindirectlyaffectedbybothdroughtandland‐usepracticesinupwindareas
thatleadtodustemissions.Whenwind‐blowndustisdepositedonmountainsnowpack,the
resultingdarkeningofthesnowallowsincreasedabsorptionofsolarradiantenergy,andearlier
meltingthanunderdustfreeconditions.Unlikewarmingtemperatures,whichadvanceboth
snowmelttimingandgrowingseasononsetforalpinevegetation,theeffectofdustdepositionon
mountainsnowpackisasourceofearliersnowmeltthatisnotdirectlylinkedtoseasonalshifting
(Steltzeretal.2009).Althoughdustdepositionmaybeasignificantcontributortosoildevelopment
insomeareas(Lawrenceetal.2011),itcanincreaseevapotranspirationanddecreaseannual
runoffflows(Deemsetal.2013).Changesinsoilmoisturelevelsduetoearliersnowmeltmay
interactwithotherclimatechangeeffectstoproducechangesinspeciescompositionandstructure
ofalpinehabitats.
Otherindirecteffectsofnon‐climatestressors–landscapecondition
Score:0.98
AlpinelandscapesinColoradoaregenerallyinexcellentcondition,andwellprotected.Ongoing
threatsfromdevelopmentinalpinehabitatsassociatedwithrecreationareasandactivities,
includingassociatedroadsandinfrastructure;thesearegenerallyarelimitedinextent.Old
privately‐ownedminingclaimsarescatteredthroughout,butthereareveryfewactivemines
operatingtodayInsouthwesternColorado,sheepgrazingandisolatedminingactivityareminor
sourcesofdisturbanceinalpineareas.Anthropogenicnitrogendepositionisanongoinginfluence
onalpinephenology(Smithetal.2012)andspeciesdiversity(Farreretal.2015)whichmay
114ColoradoNaturalHeritageProgram©2015
interactwithwarmingtemperatures,althoughthelong‐termeffectsofthisdisturbancearenotwell
known.
Literature Cited
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Predictedresponsesofarcticandalpineecosystemstoalteredseasonalityunderclimatechange.GlobalChangeBiology
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Farrer,E.C.,I.W.Ashton,M.J.Spasojevic,S.Fu,D.J.X.Gonzalez,andK.N.Suding.2015.Indirecteffectsofglobalchange
accumulatetoalterplantdiversitybutnotecosystemfunctioninalpinetundra.JournalofEcology103:351‐360.
Formica,A.,E.C.Farrer,I.W.Ashton,andK.N.Suding.2014.Shrubexpansionoverthepast62yearsinRockyMountain
alpinetundra:possiblecausesandconsequences.Arctic,Antarctic,andAlpineResearch46:616‐631.
Grafius,D.R.,G.P.Malanson,andD.Weiss.2012.SecondarycontrolsofalpinetreelineelevationsinthewesternUSA.
PhysicalGeography33:146‐164.
Greenland,D.andM.Losleben.2001.Climate.Chapter2inBowman,W.D.,andT.R.Seastedt,eds.StructureandFunction
ofanAlpineEcosystem:NiwotRidge,Colorado.NewYork:OxfordUniversityPress.
Holtmeier,F‐K.andG.Broll.2005.Sensitivityandresponseofnorthernhemispherealtitudinalandpolartreelinesto
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Hülber,K.,M.Winkler,andG.Grabherr.2010.Intraseasonalclimateandhabitat‐specificvariabilitycontrolstheflowering
phenologyofhighalpineplantspecies.FunctionalEcology24:245‐252.
Keller,F.andC.Körner.2003.Theroleofphotoperiodisminalpineplantdevelopment.Arctic,Antarctic,andAlpine
Research35:361‐368.
Körner,C.2012.Alpinetreelines:functionalecologyoftheglobalhighelevationtreelimits.Springer,Basel,Switzerland.
Lawrence,C.R.,J.C.Neff,andG.L.Farmer.2013.TheaccretionofaeoliandustinsoilsoftheSanJuanMountains,Colorado,
USA.JournalofGeophysicalResearch116,F02013,doi:10.1029/2010JF001899.
Moir,W.H.,S.G.Rochelle,andA.W.Schoettle.1999.Microscalepatternsoftreeestablishmentnearuppertreeline,Snowy
Range,Wyoming.Arctic,Antarctic,andAlpineResearch31:379‐388.
Richardson,A.D.andA.J.Friedland.2009.Areviewofthetheoriestoexplainarcticandalpinetreelinesaroundtheworld.
JournalofSustainableForestry28:218‐242.
Smith,J.G.,W.Sconiers,M.J.Spasojevic,I.W.Ashton,andK.N.Suding.2012.Phenologicalchangesinalpineplantsin
responsetoincreasedsnowpack,temperature,andnitrogen.Arctic,Antarctic,andAlpineResearch44:135‐142.
Smith,W.K.,M.J.Germino,T.E.Hancock,andD.M.Johnson.2003.Anotherperspectiveonaltitudinallimitsofalpine
timberlines.TreePhysiology23:1101‐1112.
Spasojevic,M.J.,W.D.Bowman,H.C.Humphries,T.R.Seastedt,andK.N.Suding.2013.Changesinalpinevegetationover21
years:Arepatternsacrossaheterogeneouslandscapeconsistentwithpredictions?Ecosphere4:117.
http://dx.doi.org/10.1890/ES13‐00133.1
ClimateChangeVulnerabilityAssessmentforColoradoBLM115
Steltzer,H.,C.Landry,T.H.Painter,J.Anderson,andE.Ayres.2009.Biologicalconsequencesofearliersnowmeltfrom
desertdustdepositioninalpinelandscapes.PNAS106:11629‐11634.
Williams,M.E.,M.V.Losleben,andH.B.Hamann.2002.AlpineareasintheColoradoFrontRangeasmonitorsofclimate
changeandecosystemresponse.GeographicalReview92:180‐191.
Zeigenfuss,L.C.,K.A.Schonecker,andL.K.VanAmburg.2011.UngulateherbivoryonalpinewillowintheSangredeCristo
MountainsofColorado.WesternNorthAmericanNaturalist71:86‐96.

116ColoradoNaturalHeritageProgram©2015
MONTANE GRASSLANDS
Bunch‐grassdominatedgrasslandsatelevationsbetweenfoothillsandsubalpine
D.Culver
Extentexaggeratedfordisplay
Climate Vulnerability Rank: Moderate
Vulnerability summary
Key Vulnerabilities:Warmeranddrierconditionsarelikelytofacilitatethespreadofinvasivespecies,
andmayallowwoodyspeciestoestablishingrasslands.Anincreaseinforestfireactivityunderfuture
conditionsmayallowgrasslandtoexpandintoadjacentburnedareas.
Montanegrasslandsarerankedasmoderatelyvulnerabletothe
effectsofclimatechangebymid‐century.Primaryfactors
contributingtothisrankingarevulnerabilityoftheseareato
invasivespecies,andthegenerallyhighlydisturbedconditionof
occurrences,bothofwhicharelikelytointeractwiththe
significantincreasesintemperatureacrossmuchofthe
distributionofthehabitatinColoradotoreduceresilienceof
thesehabitats.
Distribution
Montane‐subalpinegrasslandsintheColoradoRockiesaretypicallygrasslandsofforestopenings
andpark‐likeexpansesinthemontaneandsubalpineconiferousforestsatelevationsof7,200‐
10,000feet(2,200‐3,000m),intermixedwithstandsofspruce‐fir,lodgepole,ponderosa,andaspen.
AlthoughsmallermontanegrasslandsarescatteredthroughouttheSouthernRockyMountains
ecoregion,thelargestoccurrencebyfar(overamillionacres)isonthevalleyfloorofthelarge
intermountainbasinSouthParkincentralColorado.Thelargestoccurrencesareprimarilywithin
Colorado,butexamplesarescatteredthroughouttheregionfromWyomingtoNewMexico.
ClimateChangeVulnerabilityAssessmentforColoradoBLM117
Characteristic species
Theselargepatchgrasslandsareintermixedwithvarioustypesofforeststands,dependingon
elevation.Withinthesubalpinezone,forbstendtobemoreprominentathigherelevations,and
shrubsatlowerelevations(TurnerandPaulsen1976).Associationsarevariabledependingonsite
factorssuchasslope,aspect,andprecipitation,butgenerallylowerelevationmontanegrasslands
aremorexericanddominatedbymuhly(Muhlenbergiaspp.),bluebunchwheatgrass
(Pseudoroegneriaspicata),Arizonafescue(Festucaarizonica),andIdahofescue(Festuca
idahoensis),whileuppermontaneorsubalpinegrasslandsaremoremesicandmaybedominated
byThurberfescue(Festucathurberi)ortimberoatgrass(Danthoniaintermedia).Parry’soatgrass
(Danthoniaparryi)isfoundacrossmostoftheelevationalrangeofthissystem.Montanegrasslands
intheColoradoFrontRangeareoftendominatedbyspikefescue(Leucopoakingii)ormountain
muhly(Muhlenbergiamontana)(Peet1981).IntheSanJuanMountainsofsouthwesternColorado,
thesegrasslandsaredominatedbyThurberfescueandotherlargebunchgrasses(Jamiesonetal.
1996).Grassesofthefoothillsandpiedmont,suchasbluegrama(Boutelouagracilis),sideoats
grama(Boutelouacurtipendula),needle‐and‐thread(Hesperostipacomata),prairieJunegrass
(Koeleriamacrantha),westernwheatgrass(Pascopyrumsmithii),Sandbergbluegrass(Poasecunda),
andlittlebluestem(Schizachyriumscoparium)maybeincludedinlowerelevationoccurrences.
Higher,moremesiclocationsmaysupportadditionalgraminoidspeciesincludingbentgrass
(Agrostisspp.),sedge(Carexspp.),alpinefescue(Festucabrachyphylla),Drummond'srush(Juncus
drummondii),alpinetimothy(Phleumalpinum),bluegrass(Poaspp.),orspiketrisetum(Trisetum
spicatum).Woodyspeciesaregenerallysparseorabsent,butoccasionalindividualsfromthe
surroundingforestcommunitiesmayoccur.Scattereddwarf‐shrubsmaybefoundinsome
occurrences;speciesvarywithelevationandlocation.Forbsaremorecommonathigherelevations.
Environment
Thisecosystemtypicallyoccursongentletosteepslopes,parks,oronlowersideslopesthataredry,
andmayextendupto11,000ft(3,350m)onwarmaspects.Thegeneralclimateintherangeofthis
ecosystemistypicallymontanetosubalpine,characterizedbycoldwintersandrelativelycool
summers,althoughtemperaturesaremoremoderateatlowerelevations.Precipitationpatterns
differbetweentheeastandwestsidesoftheContinentalDivide.Ingeneral,thesegrasslands
experiencelongwinters,deepsnow,andshortgrowingseasons.Averageannualprecipitation
rangesbetween20to40inches(51‐102cm),andthemajorityofthisfallsassnow(Turnerand
Paulsen1976).SnowcoverinsomeareascanlastfromOctobertoMay,andservestoinsulatethe
plantsbeneathfromperiodicsubzerotemperatures.Otherareasarekeptfreefromsnowbywind.
Rapidspringsnowmeltusuallysaturatesthesoil,andwhentemperaturesriseplantgrowthis
rapid.Precipitationduringthegrowingseasonishighlyvariable,butprovideslessmoisturethan
snowmelt.Growingseasonsareshort,typicallyfromJunethroughAugustatintermediatelocations,
althoughfrostcanoccuratalmostanytime.
ThegeologyoftheSouthernRockyMountainsisextremelycomplex.Notsurprisingly,soilsarealso
highlyvariable,dependingontheparentmaterialsfromwhichtheywerederivedandthe
conditionsunderwhichtheydeveloped.Podzolicsoilshavedevelopedonmosthighmountain
areasasaresultofcooltocoldtemperatures,relativelyabundantmoisture,andthedominant
118ColoradoNaturalHeritageProgram©2015
coniferousforestvegetation.Intheintermingledparksandopentreelessslopesorridges,grassland
soilshavedeveloped.Soiltextureisimportantinexplainingtheexistenceofmontane‐subalpine
grasslands(Peet2000).Thesegrasslandsoftenoccupythefine‐texturedalluvialofcolluvialsoilsof
valleybottoms,incontrasttothecoarse,rockymaterialofadjacentforestedslopes(Peet2000).
Soilsareoftensimilartoprairiesoils,withadarkbrownA‐horizonthatisrichinorganicmatter,
welldrained,andslightlyacidic(TurnerandPaulsen1976).Otherfactorsthatmayexplainthe
absenceoftreesinthissystemaresoilmoisture(toomuchortoolittle),competitionfrom
establishedherbaceousspecies,coldairdrainageandfrostpockets,highsnowaccumulation,
beaveractivity,slowrecoveryfromfire,andsnowslides(Daubenmire1943,Knight1994,Peet
2000).Wheregrasslandsoccurintermixedwithforestedareas,thelesspronouncedenvironmental
differencesmeanthattreesaremorelikelytoinvade(TurnerandPaulsen1976).
Dynamics
Avarietyoffactors,includingfire,wind,cold‐airdrainage,climaticvariation,soilproperties,
competition,andgrazinghavebeenproposedasmechanismsthatmaintainopengrasslandsand
parksinforestsurroundings.Observationsandrepeatphotographystudiesinsitesthroughoutthe
southernRockyMountainsindicatethattreesdoinvadeopenareas,butthatthemechanisms
responsibleforthistrendmaydifferfromsitetosite.AndersonandBaker(2005)discountedfire
suppressionasthecauseoftreeinvasionsinWyoming’sMedicineBowMountains,concludingthat
edaphicconditionswerethemostlikelyfactorlimitingtreeestablishment.IntheSanJuan
MountainsofsoutheasternColorado,ZierandBaker(2006)alsofoundthattheprobabilityoftree
invasionvariedwithforesttype.Climaticvariation,fireexclusion,andgrazingappeartointeract
withedaphicfactorstofacilitateorhindertreeinvasioninthesegrasslands(ZierandBaker2006).
IntheGunnisonBasin,Schaueretal.(1998)identifiedseedlingmortalityastheprimaryfactor
preventinginvasionsofEngelmannspruce,butdidnotdetermineifthiswasduetocompetition
fromestablishedgrasslandplants,ortoedaphicconditions.TheworkofCoopandGivnish(2007)
intheJemezMountainsofnorthernNewMexicosuggeststhatbothchangingdisturbanceregimes
andclimaticfactorsarelinkedtotreeestablishmentinsomemontanegrasslands.Pocketgophers
(Thomomysspp.)areawidespreadsourceofdisturbanceinmontane‐subalpinegrasslands.The
activitiesoftheseburrowingmammalsresultinincreasedaeration,mixingofsoil,andinfiltration
ofwater,andareanimportantcomponentofnormalsoilformationanderosion(Ellison1946).In
addition,CantorandWhitham(1989)foundthatbelow‐groundherbivoryofpocketgophers
restrictedestablishmentofaspentorockyareasinArizonamountainmeadows.Theinteractionof
multiplefactorsindicatesthatmanagementforthemaintenanceofthesemontaneandsubalpine
grasslandsmaybecomplex.
Grazingbydomesticlivestockmayacttooverrideormaskwhatevernaturalmechanismis
responsibleformaintaininganoccurrence.Montane‐subalpinegrasslandswerefirstgrazedby
domesticlivestockbeginninginthelate1800’s(TurnerandPaulsen1976).Afterlower‐elevation,
moreaccessiblerangelandswereoverstockedinthe1870’sand1880’s,useofmontaneand
subalpinegrasslandsincreaseddramatically.Bytheturnofthecenturynearlyallgrazablelandwas
beingutilized,andmuchwasalreadyovergrazed(TurnerandPaulsen1976).AsNationalForests
wereestablishedfollowingtheOrganicAdministrationActof1897,regulationofgrazingonthese
highelevationgrasslandswasinstituted.UselevelspeakedneartheendofthefirstWorldWar,and
ClimateChangeVulnerabilityAssessmentforColoradoBLM119
currentuselevelsaresubstantiallylowerthanthehighestpreviouslevel(TurnerandPaulsen
1976).
Floristiccompositioninthesegrasslandsisinfluencedbybothenvironmentalfactorsandgrazing
history.Grazingisgenerallybelievedtoleadtothereplacementofpalatablespecieswithless
palatableonesmoreabletowithstandgrazingpressure(Smith1967,Paulsen1975,Brown1994,
butseeStohlgrenetal.1999).Ingeneral,palatablegrassesarereplacedbynonpalatableforbsor
shrubsundercattlegrazing(Smith1967),whilepalatableforbsarecharacteristicallyabsentfrom
grasslandswithalonghistoryofsheepuse(TurnerandPaulsen1976).Annualspeciesare
uncommonexceptonheavilydisturbedareas.Someoccurrencesaredominatedbyseededpasture
grasses,especiallysmoothbrome(Bromusinermis),timothy(Phleumpratense),andKentucky
bluegrass(Poapratensis).
Historically,soildisturbancewaslargelytheresultofoccasionalconcentrationsoflargenative
herbivores,orthediggingactionoffossorialmammals.Domesticlivestockranchinghaschanged
thetimingandintensityofgrazingdisturbancefromthatofnativeherbivores,withthepotentialto
alterspeciescomposition,soilcompaction,nutrientlevels,andvegetationstructure.Incombination
withgrazingofdomesticlivestock,various“rangeimprovement”activities(e.g.seeding,rodent
control,herbicideapplication)havethepotentialtoalternaturalecosystemprocessesandspecies
composition.Increasingsmall‐acreageexurbandevelopmentwithlivestock(“ranchettes”)appears
tobeincreasingtheincidenceofweedyexoticspeciesinthesehabitats.ExoticsincludeDalmatian
toadflax(Linariadalmatica),knapweed(Centaureaspp.),cheatgrass(Bromustectorum),
sweetclover(Melilotusofficinalis),andothers.
CCVA Scoring
Exposure‐Sensitivity (Potential Impact) Rank
PercentColoradoacreswithprojectedtemp>max&pptdelta<5%1.0%
InitialExposure‐SensitivityRankLow
PercentColoradoacreswithtemp<=max&pptdelta<5%morethan50%?Yes(79.6%)
FinalExposure‐SensitivityRankModerate
Exposuretotemperaturechange
Underprojectedmid‐centurytemperatures,about1%ofthecurrentrangeofmontanegrasslandin
Coloradowouldexperienceannualmeantemperaturesabovethecurrentstatewidemaximum.
Exposuretoprecipitationchange
About81%ofmontanegrasslandinColoradowillbeexposedtoeffectivelydrierconditionseven
underunchangedorslightlyincreasedprecipitationprojectedformid‐century.
Sensitivityofecosystemtotemperatureandprecipitation
Higherelevationgrasslandsarecharacterizedbycoldwintersandrelativelycoolsummers,
althoughtemperaturesaremoremoderateatlowerelevations.
120ColoradoNaturalHeritageProgram©2015
Soiltexturehasasignificanteffectonthedistributionandpersistenceofmontane‐subalpine
grasslands(Peet2000),determiningsoilmoistureconditionsthatacttoexcludetrees.Droughtand
warmertemperaturesmaychangespeciescomposition,orallowinvasionbydrought‐tolerant
shrubsorinvasivespeciesinsomeareas.
Resilience and Adaptive Capacity Rank
OverallScore: 0.74Rank: High
Bioclimaticenvelopeandrange
Averagedcategoryscore:0.82
Thesegrasslandsarenotrestrictedtohighelevations,andarewellwithinthecoreareaoftheir
continentaldistributioninColorado.Thevariationpresentinthevariousgrasslandoccurrences
givesthisecosystemawideecologicalamplitude,covering79%ofColorado’soverallprecipitation
range,and48%ofthegrowingdegreerange.Thesefactorscombinetogivemontanegrasslandsa
highresiliencescoreinthiscategory.
Growthformandintrinsicdispersalrate
Score:1
Thisecosystemisdominatedbyrelativelyfastgrowinggraminoidandherbaceousspecies,andis
abletodispersetoavailablehabitatquicklyincomparisonwithecosystemsdominatedbywoody
species.
Vulnerabilitytoincreasedattackbybiologicalstressors
Score:0.5
TheworkofCoopandGivnish(2007)intheJemezMountainsofnorthernNewMexicosuggests
thatbothchangingdisturbanceregimesandclimaticfactorsarelinkedtotreeestablishmentin
somemontanegrasslands.Increasedtreeinvasionintomontanegrasslandswasapparentlylinked
tohighersummernighttimetemperatures,andlessfrostdamagetotreeseedlings;thistrendcould
continueunderprojectedfuturetemperatureincreases.Increaseddisturbancemayalsofacilitate
thecontinuedspreadofintroducedexoticspeciesasclimateconditionschange.Theinteractionof
multiplefactorsindicatesthatmanagementforthemaintenanceofthesemontaneandsubalpine
grasslandsmaybecomplex.
Vulnerabilitytoincreasedfrequencyorintensityofextremeevents
Score:1
Althoughincreasedincidenceorseverityofdroughtmayacttohelppreventtreeinvasioninto
montanegrasslands,thereissomeevidencethatwarmer,driersoilconditionscouldfacilitateshrub
growthinmontanemeadowsorotherwisealterspeciescomposition(Perforsetal.2003).
ClimateChangeVulnerabilityAssessmentforColoradoBLM121
Otherindirecteffectsofnon‐climatestressors–landscapecondition
Score:0.37
MontanegrasslandlandscapesinColoradoarehighlyalteredbyanthropogenicdisturbance.Higher
elevationgrasslandsonrelativelyflatsitesareofteninprivateownership,andareoftenvulnerable
tosubdivisionforresidentialdevelopmentand/ortransportationcorridordevelopment.The
extensivegrasslandsofSouthPark,inparticular,arethreatenedbythesubdivisionoflarge
properties,anddevelopmentoftransportationcorridors.Recreationaluse(publicopenspaceuse
inlowerelevations;hunters,packersandsnow‐mobilersinhigherelevations)isanongoingsource
ofdisturbanceinthishabitat.
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Jamieson,D.W.,W.H.Romme,andP.Somers.1996.Bioticcommunitiesofthecoolmountains.Chapter12inTheWestern
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knowledgebyrangeecosystems.USDAForestServiceResearchPaperRM‐154.RockyMountainForestandRange
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
ClimateChangeVulnerabilityAssessmentforColoradoBLM123
SEMI‐DESERT GRASSLAND
Drygrasslandscharacterizedbydrought‐tolerantbunchgrassspeciesandscatteredshrubs
P.Lyon
extentexaggeratedfordisplay
Climate Vulnerability Rank: Low
Vulnerability summary
Key Vulnerabilities:Climaterelatedvulnerabilityforthesegrasslandsisminimal,buttheimpacted
conditionofmanystandsmayinhibittheirpotentialforexpansion.
Lowexposureandsensitivitytoprojectedconditionsoutsidethe
currentrangeexperiencedbythesegrasslandsistheprimary
factorcontributingtothelowvulnerabilityrankingofthis
ecosystem.Thegenerallyfairtopoorconditionofmany
occurrencesinColoradomaytendtoinhibitthepotentialofthis
ecosystemtoexploitandmoveintonewareasunderfuture
climateconditions.
Distribution
ThesearethedriestgrasslandsoftheintermountainwesternU.S.,occurringinlargepatchesin
mosaicswithshrublandsystemsdominatedbysagebrush,saltbush,blackbrush,mormon‐tea,and
othershrubspecies.Climatesaresemi‐aridtoarid.Colorado’ssemi‐desertgrasslandsarefound
primarilyondryplainsandmesasofthewestslopeatelevationsof4,750‐7,600feet
Characteristic species
Thesegrasslandsaretypicallydominatedbydrought‐resistantperennialbunchgrassessuchas
Indianricegrass(Achnatherumhymenoides),bluegrama(Boutelouagracilis),needle‐and‐thread
124ColoradoNaturalHeritageProgram©2015
(Hesperostipacomata),ringmuhly(Muhlenbergiatorreyi),orJames'galleta(Pleuraphisjamesii),or
bluebunchwheatgrass(Pseudoroegneriaspicata).Scatteredshrubsandsub‐shrubsmaybepresent,
includingsagebrush(Artemisiaspp.),saltbush(Atriplexspp.),jointfir(Ephedraspp.),snakeweed
(Gutierreziasarothrae),orwinterfat(Krascheninnikovialanata).Blackbrush(Coleogyne
ramosissima)isuncommoninColoradooccurrences,buttypicalfurtherwest.
Environment
WestSlopelow‐elevationgrasslandsoccurinsemi‐aridtoaridclimateswithcoldtemperate
conditions.Hotsummersandcoldwinterswithfreezingtemperaturesandsnowarecommon.
GrasslandsofthewesternvalleysreceiveasignificantportionofannualprecipitationinJuly
throughOctoberduringthesummermonsoonstorms,withtherestfallingassnowduringthe
winterandearlyspringmonths.Annualprecipitationisusuallyfrom8‐16in(20‐40cm).
Thesegrasslandsoccurinxericlowlandanduplandareasandmayoccupyswales,playas,mesa
tops,plateauparks,alluvialflats,andplains.Substratesaretypicallywell‐drainedsandstone‐or
shale‐derivedsoils.Somesandysoiloccurrenceshaveahighcoverofcryptogamsonthesoil.Soil
salinitydependsontheamountandtimingofprecipitationandflooding.
Dynamics
Thissystemismaintainedbyfrequentfiresthateliminatewoodyplants.Acombinationof
precipitation,temperature,andsoilslimitsthissystemtothelowerelevationswithintheregion.
Thedominantperennialbunchgrassesandshrubswithinthissystemareallverydrought‐resistant
plants.Grassesthatdominatesemi‐aridgrasslandsdevelopadensenetworkofrootsconcentrated
intheupperpartsofthesoilwhererainfallpenetratesmostfrequently.
Thesemi‐desertgrasslandsystemisvulnerabletoinvasionbyexoticspecies,particularly
cheatgrass(Bromustectorum).Althoughfrequentfiresingrasslandsmayhavebeencommon
historically,theintroductionofcheatgrasshasalteredthedynamicsofthesystem,increasingboth
firefrequencyandpost‐firecheatgrassdominance(ShinnemanandBaker2009,Balchetal.2013).
Cheatgrassiseasilyignited,andalsoprovidesanabundanceoffinefuelsthatcarryfire(Knapp
1998).
Floristiccompositioningrasslandsisinfluencedbybothenvironmentalfactorsandgrazinghistory.
Manygrasslandoccurrencesarealreadyhighlyalteredfrompre‐settlementcondition.Grazingis
generallybelievedtoleadtothereplacementofpalatablespecieswithlesspalatableonesmore
abletowithstandgrazingpressure(Smith1967,Paulsen1975,Brown1994,butseeStohlgrenetal.
1999).Grazingbydomesticlivestockmayacttooverrideormaskwhatevernaturalclimaticor
edaphicmechanismisresponsibleformaintaininganoccurrence.Thishabitatisalsoadaptedto
grazingandbrowsingbynativeherbivoresincludingdeer,elk,bison,andpronghorn,aswellas
burrowingandgrazingbysmallmammalssuchasgophers,prairiedogs,rabbits,andground
squirrels.Activitiesoftheseanimalscaninfluencebothvegetationstructureandsoildisturbance,
potentiallysuppressingtreeestablishment.Periodicdroughtiscommonintherangeoffoothilland
semi‐desertgrasslands,butmaynotbeasgreatafactorinthevegetationdynamicsofthissystem
asingrasslandsoftheplains.
ClimateChangeVulnerabilityAssessmentforColoradoBLM125
Remnantstandsofdesertgrasslandshavebeenhighlyalteredbylivestockgrazing,anditislikely
thatgrasslandsformerlyoccupiedsomesitesthatarenowcoveredbypinyon‐juniperorshrubland
(Dick‐Peddie1993).Grazingbydomesticlivestockcanalsoinfluencetherelativeproportionof
cool‐vs.warm‐seasongrasses,orfavortheincreaseofwoodyshrubspecies.
CCVA Scoring
Exposure‐Sensitivity (Potential Impact) Rank
PercentColoradoacreswithprojectedtemp>max&pptdelta<5%14.0%
InitialExposure‐SensitivityRankLow
PercentColoradoacreswithtemp<=max&pptdelta<5%morethan50%?No(35.2%)
FinalExposure‐SensitivityRankLow
Exposuretotemperaturechange
Underprojectedmid‐centurytemperatures,about19%ofthecurrentrangeofsemi‐desert
grasslandinColoradowouldexperienceannualmeantemperaturesabovethecurrentstatewide
maximum.
Exposuretoprecipitationchange
About49%ofsemi‐desertgrasslandinColoradowillbeexposedtoeffectivelydrierconditionseven
underunchangedorslightlyincreasedprecipitationprojectedformid‐century.
Sensitivityofecosystemtotemperatureandprecipitation
Semi‐desertgrasslandspeciesaregenerallydroughttolerant(Dick‐Peddie1993),andareadapted
tolowprecipitationlevelsandalonggrowingseason.Soilsaretypicallyaridisols,whicharedryfor
mostoftheyear,evenduringthegrowingseason,andthereislittleinfiltrationofwaterintothesoil
(SimsandRisser2000).Changesinthetimingandamountofprecipitationcanaffectthestructure
andpersistenceofgrasslands.Withtheircomparitivelyshallowerrootsystems,grasseshavean
advantageovershrubsonshallow,poorlydrainedsoils,whereasshrubsarefavoredondeepersoils
wherewinterprecipitationcanpenetratedeeplyintothesoil.BecauseshrubsareC3plantswith
highercool‐seasonactivity(AsnerandHeidebrecht2005)theyareabletoutilizewinter
precipitationtoagreaterextentthanarewarm‐seasongrasses.SimsandRisser(2000)reportthat
ameanannualtemperatureof50F(10C)isathresholdbetweengrasslandsdominatedbycool‐
season(C3)grassesandthosedominatedbywarm‐season(C4)species.However,Munsonetal.
(2011)reportadeclineinperennialvegetationcoveringrasslandsoftheColoradoPlateauwith
increasesintemperature.
Resilience and Adaptive Capacity Rank
OverallScore: 0.72Rank: High
Bioclimaticenvelopeandrange
Averagedcategoryscore:0.59
126ColoradoNaturalHeritageProgram©2015
Thesegrasslandsarenotrestrictedtohighelevations,noraretheyatthesouthernendoftheir
continentaldistributioninColorado.However,becausetheyoccurinthewarmestanddriestparts
ofthestate,theyoccupyonly1%ofColorado’soverallprecipitationrange,and34%ofthe
statewidegrowingdegreedayrange.Thesefactorscombinetolowertheoverallresiliencescorein
thiscategory,butmaybesomewhatoverstatedduetothecurrentlimiteddistributionofthistype
inColorado.
Growthformandintrinsicdispersalrate
Score:1
Thisecosystemisdominatedbyrelativelyfastgrowinggraminoidandherbaceousspecies,andis
abletodispersetoavailablehabitatquicklyincomparisonwithecosystemsdominatedbywoody
species.
Vulnerabilitytoincreasedattackbybiologicalstressors
Score:0.5
Semi‐desertgrasslandsarevulnerabletoinvasionbyexoticspecies,particularlycheatgrass.
Extendeddroughtcanleadtowidespreadmortalityofperennialgrassesandallowtheinvasionof
cheatgrass.
Vulnerabilitytoincreasedfrequencyorintensityofextremeevents
Score:1
Droughtandwarmertemperaturesmaychangespeciescomposition,orallowinvasionbydrought‐
tolerantwoodyorinvasivespeciesinsomeareas.Droughtcanincreaseextentofbaregroundand
decreaseforbcoverage,especiallyinmorexericgrasslands(Debinskietal.2010).
Althoughfrequentfiresingrasslandsmayhavebeencommonhistorically,theintroductionof
cheatgrasshasalteredthedynamicsofthesystem,andfireoftenresultsincheatgrassdominance.
Onceovertakenbycheatgrass,morefrequentfiresareencouragedbythedryflammablematerial,
leadingtofurtherdominationbycheatgrass.Evenafewcheatgrassplantsinastandwillproduce
enoughseedtodominatethestandwithinafewyearsafterfire.Increasingdroughtislikelyto
facilitatethistrend.
Otherindirecteffectsofnon‐climatestressors–landscapecondition
Score:0.51
Semi‐desertgrasslandlandscapesinColoradohavebeensignificantlyimpactedbyanthropogenic
activity,especiallyconversiontoagricultureinareasnearrivers.Thecurrentrateofconversionof
lowerelevationnativegrasslandtoagricultureislow,butremainsathreatforsomelimitedareas.
Nativegrasslandhabitatcanalsobelostorfragmentedbysuburbanandexurbandevelopment,and
transportation,oilandgas,orutilityinfrastructuredevelopment.
ClimateChangeVulnerabilityAssessmentforColoradoBLM127
Literature Cited
Asner,G.P.andK.B.Heidebrecht.2005.Desertificationaltersregionalecosystem‐climateinteractions.GlobalChange
Biology11:182‐194.
Balch,J.K.,B.A.Bradley,C.M.D’Antonio,andJ.Gómez‐Dans.2013.Introducedannualgrassincreasesregionalfireactivity
acrossthearidwesternUSA(1980‐2009).GlobalChangeBiology19:173‐183.
Brown,D.E.1994.Grasslands.InBioticcommunities:southwesternUnitedStatesandnorthwesternMexico.D.E.Brown,
ed.UniversityofUtahPress,SaltLakeCity,UT.
Debinski,D.M.,H.Wickham,K.Kindscher,J.C.Caruthers,andM.Germino.2010.Montanemeadowchangeduringdrought
varieswithbackgroundhydrologicregimeandplantfunctionalgroup.Ecology91:1672‐1681.
Dick‐Peddie,W.A.1993.NewMexicovegetation,past,present,andfuture.WithcontributionsbyW.H.MoirandRichard
Spellenberg.UniversityofNewMexicoPress,Albuquerque,NewMexico.
Knapp,P.A.1998.Spatio‐temporalpatternsoflargegrasslandfiresintheIntermountainWest,USA.GlobalEcologyand
Biogeography7:259–272.
Munson,S.M.,J.Belnap,C.D.Schelz,M.Moran,andT.W.Carolin.2011.Onthebrinkofchange:plantresponsestoclimate
ontheColoradoPlateau.Ecosphere2:art68.
Paulsen,H.A.,Jr.1975.RangemanagementinthecentralandsouthernRockyMountains:asummaryofthestatusofour
knowledgebyrangeecosystems.USDAForestServiceResearchPaperRM‐154.RockyMountainForestandRange
ExperimentStation,USDAForestService,FortCollins,Colorado.
Shinneman,D.J.andW.L.Baker.2009.Environmentalandclimaticvariablesaspotentialdriversofpost‐firecoverof
cheatgrass(Bromustectorum)inseededandunseededsemiaridecosystems.InternationalJournalofWildlandFire
18:191‐202.
Sims,P.L.,andP.G.Risser.2000.Grasslands.Chapter9in:Barbour,M.G.,andW.D.Billings,eds.,NorthAmerican
TerrestrialVegetation,SecondEdition.CambridgeUniversityPress.
Smith,D.R.1967.Effectsofcattlegrazingonaponderosapine‐bunchgrassrangeinColorado.USDAForestService
TechnicalBulletinNo.1371.RockyMountainForestandRangeExperimentStation,USDAForestService,FortCollins,
Colorado.
Stohlgren,T.J.,L.D.Schell,andB.VandenHuevel.1999.Howgrazingandsoilqualityaffectnativeandexoticplant
diversityinrockymountaingrasslands.EcologicalApplications9:45‐64. 
128ColoradoNaturalHeritageProgram©2015
SHORTGRASS PRAIRIE
Grasslandsdominatedbybluegrama
R.Rondeau
extentexaggeratedfordisplay
Climate Vulnerability Rank: High
Vulnerability summary
Key Vulnerabilities:Warmersummernighttimelowtemperaturesand/orextendedperiodsofdrought
arelikelytochangethebalanceofwarm‐andcool‐seasongrasses,and,iffirefrequencyremainslow,
allowtheestablishmentofwoodyspecies,withthepotentialforconversiontoamorearidgrassland
typeorsavanna.
Shortgrassprairieisrankedashavinghighvulnerabilitytothe
effectsofclimatechangebymid‐century.Primaryfactors
contributingtothisrankingarethefactthatthesegrasslandsare
foundontheeasternplainsofColorado,wherethegreatestlevels
ofexposureforalltemperaturevariablesoccur.Inaddition,
anthropogenicdisturbanceinthesegrasslandshasreducedthe
overalllandscapeconditionofthehabitat,whichislikelyto
reduceitsresilienceinthefaceofincreasingfrequencyof
extremeevents.
Distribution
Shortgrassprairieischaracteristicofthewarm,drysouthwesternportionoftheGreatPlains,lying
totheeastoftheRockyMountains,andrangingfromtheNebraskaPanhandlesouthintoTexasand
NewMexico.ThehighplainsoftheLlanoestacadodefinethesouthernextentoftheshortgrass
prairie,boundedbyescarpmentsformedintheOgalallaCaprock(calledtheMescaleroescarpment
tothewestandtheCaprockescarpmentontheeast).Theeasternboundaryoftheshortgrass
prairieisafluctuatingecotoneontheeast‐westprecipitationgradientbetweenshortandmidgrass
ClimateChangeVulnerabilityAssessmentforColoradoBLM129
prairie,definedbyatransitionareawhereprecipitationbecomesinsufficienttoprovidesoil
moistureforthetallergrasses(Shantz1923,Carpenter1940).Thenorthernboundaryrepresents
thetransitiontocooler,moremesicmixed‐grasstypes,generallyoccuringinsoutheastern
WyomingandsouthwesternNebraska,althoughoccasionalshortgrassstandsmaybefoundfurther
north.Inspiteofextensiveconversiontoagricultureorotheruses,shortgrassprairiestillforms
extensivetractsontheeasternplainsofColorado,atelevationsbelow6,000feet.
Characteristic species
Thissystemspansawiderangeandthustherecanbesomedifferencesintherelativedominanceof
somespeciesfromnorthtosouthandfromeasttowest.
Priortosettlement,theshortgrassprairiewasagenerallytreelesslandscapecharacterizedbyblue
grama(Boutelouagracilis)andbuffalograss(Buchloedactyloides).Inmuchofitsrange,shortgrass
prairieformsthematrixvegetationwithbluegramadominant.Othergrassesincludethree‐awn
(Aristidapurpurea),side‐oatsgrama(Boutelouacurtipendula),hairygrama(Bouteloua
hirsuta),needle‐and‐thread(Hesperostipacomata),Junegrass(Koeleriamacrantha),western
wheatgrass(Pascopyrumsmithii),James'galleta(Pleuraphisjamesii),alkalisacaton(Sporobolus
airoides),andsanddropseed(Sporoboluscryptandrus).Localinclusionsofmesicorsandysoilsmay
supporttallergrassspeciesincludingsandbluestem(Andropogonhallii),littlebluestem
(Schizachyriumscoparium),Indiangrass(Sorghastrumnutans),andprairiesandreed(Calamovilfa
longifolia),aswellasscatteredshrubspeciesincludingsandsage(Artemisiafilifolia),prairie
sagewort(Artemisiafrigida),fourwingsaltbush(Atriplexcanescens),treecholla(Cylindroputia
imbricata),spreadingbuckwheat(Eriogonumeffusum),snakeweed(Gutierreziasarothrae),pale
wolfberry(Lyciumpallidum),andsoapweedyucca(Yuccaglauca)mayalsobepresent.One‐seed
juniper(Juniperusmonosperma)andoccasionalpinyonpine(Pinusedulis)treesareoftenpresent
onshalebreakswithintheshortgrassprairiematrix.
Thisecosystem,incombinationwiththeassociatedwetlandsystems,representsoneoftherichest
areasintheUnitedStatesforlargemammals.Ahealthyshortgrassprairiesystemshouldsupport
endemicgrasslandbirds,prairiedogcomplexes,viablepopulationsofpronghorn,andotherGreat
Plainsmammals.Historically,suchareaswouldalsohavebeenpopulatedbybisoninsufficient
numberstosupportpopulationsofwolves.Grasslandbirdspeciesmayconstituteoneofthefastest
decliningvertebratepopulationsinNorthAmerica(Knopf1996).
Environment
Theclimateoftheshortgrassprairieischaracterizedbylargeseasonalcontrasts,aswellas
interannualandlongertermvariability(PielkeandDoesken2008).Wintersintheshortgrass
prairiecanbemildanddrywhenPacificairmassesareblockedbytheRockyMountainsunder
zonalflowconditions,orcoldandsnowyundermeridionalflowpatternsthatbringarcticairor
upslopesnow.Springistransitionalwithwarmingconditionsandlingeringarcticairandpossible
heavysnow.Springwarmingbringsthermalinstabilityandatmosphericmixingproducingwindy
conditions,andthunderstormsbecomecommon.Tornadosandslow‐movingstormsproducing
heavyprecipitationmayalsooccur.InsummeradrylineseparatinghumidGulfairfromdrydesert
southwestairformsinthewesternplains,andthunderstormsoftenformalongthisboundary.
130ColoradoNaturalHeritageProgram©2015
Summerthunderstormscanproducelocallyheavyprecipitation.Inlatesummer,theNorth
Americanmonsooncanbringmoisturefromthesouthwest.Typicalautumnweatherinthe
shortgrassregionisrelativelyfairanddry,withperiodiccool,wetweatherandthepossibilityof
earlysnow(PielkeandDoesken2008).
Thesegrasslandsoccurprimarilyonflattorollinguplandswithloamy,ustic(dry,butusuallywith
adequatemoistureduringgrowingseason)soilsrangingfromsandytoclayey,atelevations
generallybelow6,000feet(1,830m).Organicmatteraccumulationinshortgrassprairiesoilsis
primarilyconfinedtotheupper8in(20cm,Kellyetal.2008).Theactionofafreeze‐thawcycleon
thesegrasslandsoilsincreasestheirvulnerabilitytowinderosioninlatewinterandspring(Pielke
andDoesken2008).
Dynamics
Large‐scaleprocessessuchasclimate,fireandgrazinginfluencethissystem.Theroleoffirein
maintainingherbaceouscoverandsuppressingwoodyvegetationiswelldemonstratedinmost
prairietypes.Althoughfireisofsomewhatlesserimportanceinshortgrassprairiecomparedto
otherprairietypes,itisstillasignificantsourceofdisturbance(Engleetal.2008),anddocumented
historicfireswereoftenexpansive.Bothfloraandfaunaoftheshortgrassprairiearesensitiveto
theseasonalityandfrequencyoffire(FordandMcPherson1997).Largescaleclimaticconditions
acttodetermineseasonalityandfrequencyofwildfireontheshortgrassprairie,whileextentand
localfireeffectsaredependentontopographicandedaphicconditions.Thexericclimateofthe
shortgrassreducesoverallfuelloads,butalsodriesvegetationsufficientlyforittobecome
flammable.Thegenerallyopen,rollingplainsandoftenwindyconditionsintheshortgrassprairie
facilitatethespreadoffirewhenfuelloadsaresufficient(Axelrod1985).Conversly,breaksand
rockyareasthatareprotectedfromfireareabletosupportwoodyvegetation,eveninthedry
conditionstypicaloftheregion(Wells1965).
Theshortgrassesthatdominatethissystemareextremelydrought‐andgrazing‐tolerant.These
speciesevolvedwithdroughtandlargeherbivoresand,becauseoftheirstature,arerelatively
resistanttoovergrazing.
CCVA Scoring
Exposure‐Sensitivity (Potential Impact) Rank:
PercentColoradoacreswithprojectedtemp>max&pptdelta<5%58.3%
InitialExposure‐SensitivityRankHigh
PercentColoradoacreswithtemp<=max&pptdelta<5%morethan50%?No(20.2%)
FinalExposure‐SensitivityRankHigh
Exposuretotemperaturechange
Underprojectedmid‐centurytemperatures,about57%ofthecurrentrangeofshortgrassprairiein
Coloradowouldexperienceannualmeantemperaturesabovethecurrentstatewidemaximum.
ClimateChangeVulnerabilityAssessmentforColoradoBLM131
Exposuretoprecipitationchange
About78%ofshortgrassprairieinColoradowillbeexposedtoeffectivelydrierconditionseven
underunchangedorslightlyincreasedprecipitationprojectedformid‐century.
Sensitivityofecosystemtotemperatureandprecipitation
Temperaturesintheshortgrassregionshowsignificantvariationbothdailyandseasonally.
Averagedailytemperaturespansare25‐30°F,anddiurnalvariationisgenerallygreatestin
summer.Wintertemperaturesarecold,withnightsbelowfreezingandchillydaytime
temperatures.Seasonalextremelowsbelow‐20°F(‐29°C)havebeenrecordedthroughoutmostof
theregion(WRCC2014).Ingeneral,thenumberoffrostfreedaysisgreaterinmoresouthern
latitudes,althoughfreezingtemperatureshavebeenrecordedinallmonthsexceptJulyandAugust.
Summermaximumtemperaturesarefrequentlyinthe90’s,especiallyinsouthernlocations;
temperaturesof100°F(38°C)orabovehavebeenrecordedeveninthenorthernpartofthe
shortgrassprairie(WRCC2014).
Grasslandsinareaswheremeanannualtemperatureisabove50°F(10°C)aregenerallydominated
byC4(warm‐season)grassspecies,whicharetolerantofwarmertemperaturesandmoreefficient
inwateruse(SimsandRisser2000).InColorado,shortgrassprairiehasahistoricannualmean
temperatureslightlygreaterthan50°F,althoughtherangeincludesslightlycoolerannualmean
temperaturesaswell.Althoughthesegrasslandsareadaptedtowarm,dryconditions,Alwardetal.
(1999)foundthatwarmingnight‐timetemperaturesinspringweredetrimentaltothegrowthof
bluegrama,andinsteadfavoredcool‐season(C3)species,bothnativeandexotic.Consequently,the
effectofincreasingtemperaturesonshortgrassprairieisdifficulttopredict.
PrecipitationtrendsintheshortgrassprairiearesimilartothoseofthelargerGreatPlainsarea,in
thatwesternareasaredriest.Annualprecipitationisgenerallylessthan20inches(51cm),and
soilsareperiodicallymoistonlyinashallowtoplayertypicallylessthan1‐2feetdeep(Shantz
1923).Meanannualprecipitationvariesfrom20+inchesintheeastto12inches(30cm)insome
westernlocations(PielkeandDoesken2008).Precipitationmaybethemostimportantecological
driverintheshortgrassprairie.LauenrothandSala(1992)foundthatshortgrassproductivitywas
primarilyinfluencedbyprecipitationratherthantemperatureinnortheasternColorado.Alarge
proportion(70‐80%)ofannualprecipitationfallsduringthegrowingseason(WRCC2014),and
mostofthisisreceivedduringalimitednumberoflargerainfallevents(PielkeandDoesken2008).
Dailyprecipitationamountsaretypicallyquitesmall(5mmorless),anddonotcontribute
significantlytosoilwaterrecharge,whichinsteadisprimarilydependentonlargebutinfrequent
rainfallevents(Partonetal.1981,Heisler‐Whiteetal.2008).Snowfallamountsarehighestinthe
north,butgenerallysnowisasmallcomponentofannualprecipitation.Mostoftheannual
precipitationisquicklyevaporatedandtranspiredintotheatmosphereratherthansoakingintothe
soil(PielkeandDoesken2008).Largerrainfalleventspermitdeepermoisturepenetrationinthe
soilprofile,andenableanincreaseinabove‐groundnetprimaryproduction(Heisler‐Whiteetal.
2008).
Soilmoisturelevelisakeydeterminantofthedistributionofshortgrassprairiehabitat;changein
precipitationseasonality,amount,orpatternwillaffectsoilmoisture.Grasslandsgenerallyoccurin
132ColoradoNaturalHeritageProgram©2015
areaswherethereisatleastoneannualdryseasonandsoilwateravailabilityislowerthanthat
requiredfortreegrowth(Partonetal.1981,SimsandRisser2000).Soilwateravailabilityactson
bothplantwaterstatusandnutrientcycling(Salaetal.1992).Thedominantshortgrassspecies
bluegramaisabletorespondquicklytoverysmallrainfallevents,althoughthisabilityis
apparentlyreducedduringextendeddroughtperiods(SalaandLauenroth1982,Salaetal.1982,
CherwinandKnapp2012).Nevertheless,bluegramaexhibitedextensivespreadduringthedrought
oftheDustbowlyears(AlbertsonandWeaver1944).Iflargerainfalleventsaremorecommon,the
sensitivityofshortgrassprairieisreduced(CherwinandKnapp2012).
Warmeranddrierconditionswouldbelikelytoreducesoilwateravailabilityandotherwisehave
detrimentaleffectsonecosystemprocesses,whilewarmerandwetterconditionscouldbe
favorable.Furthermore,changingclimatemayleadtoashiftintherelativeabundanceand
dominanceofshortgrassprairiespecies,givingrisetonovelplantcommunities(Polleyetal.2013).
BecausewoodyplantsaremoreresponsivetoelevatedCO2,andmayhavetaprootscapableof
reachingdeepsoilwater(Morganetal.2007),anincreaseofshrubbyspecies(e.g.,cholla,yucca,
snakeweed,sandsage),orinvasiveexoticspecies,especiallyinareasthataredisturbed(for
instance,byheavygrazing)mayalsoresult.
Resilience and Adaptive Capacity Rank
OverallScore: 0.62Rank: Moderate
Bioclimaticenvelopeandrange
Averagedcategoryscore:0.66
Shortgrassprairieexperiencesamuchdrierandwarmerclimatethanmostotherhabitattypesin
Colorado.Annualaverageprecipitationisontheorderof10‐18inches(25‐47cm),withameanof
15in(38cm),andthegrowingseasonisgenerallylong,withfrequenthightemperatures.
Growthformandintrinsicdispersalrate
Score:1
Thisecosystemisdominatedbyrelativelyfastgrowinggraminoidandherbaceousspecies,andis
abletodispersetoavailablehabitatquicklyincomparisonwithecosystemsdominatedbywoody
species.
Vulnerabilitytoincreasedattackbybiologicalstressors
Score:0.5
Theshortgrassesthatcharacterizethishabitatareextremelydrought‐andgrazing‐tolerant.These
speciesevolvedwithdroughtandlargeherbivoresand,becauseoftheirstature,arerelatively
resistanttoovergrazing.Grazingbydomesticlivestockistheprimaryuseofremainingshortgrass
prairie.Managementforincreasedlivestockproductiontendstoproduceamorehomogeneous
grasslanddominatedbykeyforagespecies(FuhlendorfandEngle2001),andrequiresadditional
managementefforttorestoreamosaicofhabitatstructuresuitableforcharacteristicwildlife
ClimateChangeVulnerabilityAssessmentforColoradoBLM133
species.Thus,thereisanongoingthreatofhabitatdegradationorlossoffunctionforshortgrass
prairie.Intactshortgrassprairiehasgenerallyresistedinvasionbynon‐nativespecies(Kotanenet
al.1998),includingcheatgrass(Bromustectorum),butdisturbedareasaremoresuceptibleto
invasion.
Vulnerabilitytoincreasedfrequencyorintensityofextremeevents
Score:0.5
Droughthasbeenanaturalprocessinshortgrassprairiebothduringhistoricalrecording,andin
centuriespriortoEuropeansettlement.Moreover,thereisevidencefortheoccurrenceofmega‐
droughtsthatsignificantlyeclipsedtheDustBowlyearsinseverity,duration,andspatialextent
(WoodhouseandOverpeck1998).Althoughshortgrassprairiehasadaptedtoandpersistedunder
conditionsofextremedrought,thedifferentialimpactofdroughtoncomponentspeciesmayalter
speciescomposition(Rondeauetal.2013).Cultivationofmarginallandsmaycompoundthe
vulnerabilityofremainingshortgrassoccurrencestoincreaseddroughtintensityorfrequency.
Dryclimateconditionscandecreasethefuelloadandthustherelativefirefrequencywithinthe
ecosystem.Currently,firesuppressionandcertaingrazingpatternsintheregionhavelikely
decreasedthefirefrequencyevenmore,anditisunlikelythatfirefrequencyandintensitywould
increaseunderprojectedclimateconditions.However,morefrequentoccurrenceofclimate
extremes(e.g.,verywetconditionsfollowedbyverydryconditions)couldincreasethefrequency
andextentofgrasslandwildfires(Polleyetal.2013).
Otherindirecteffectsofnon‐climatestressors–landscapecondition
Score:0.44
ShortgrasslandscapesinColoradohavebeenheavilyimpactedbyanthropogenicdisturbance,
especiallyinthenortheasternpartofthestate.Alargepartoftherangeforthissystemhasbeen
convertedtoagriculture.AreasinsoutheasternColoradohavebeenimpactedbytheunsuccessful
attemptstodevelopdrylandcultivationpreceedingtheDustBowlofthe1930s.Habitatlossisa
continuingthreattoshortgrassprairie.Tilledagriculturehasbeenlargelysurpassedbyincreasing
urbanizationastheprimarysourceofshortgrassprairiehabitatconversion,althoughthereissome
possibilitythatthiscouldreverseifdemandfordrylandbiofuelcropsweretoaccelerate.Inthe
northeasternportionofColorado,patternsofcultivatedlandhavelargelyfragmentedthematrixof
theshortgrassprairie,reducingoreliminatingconnectivityforspeciesthatdependonthem,and
thistrendislikelytocontinue.Residentialandcommercialdevelopmentisasignificantsourceof
habitatlossandfragmentationonthewesternmarginsofColorado’sshortgrassprairie
distribution,lesssoinotherareas,butrarelyentirelyabsent.
Developmentofoilandgasresourcesisongoinginshortgrassprairiehabitat,especiallyinthe
NiobrarashaleoftheDenver‐JulesburgBasinthatliesundermostofthenorthernportionof
shortgrassprairieextentinColorado.Thedensityofassociatedroads,pipelinecorridors,and
infrastructureisaprimaryongoingsourceofanthropogenicdisturbance,fragmentation,andlossin
thishabitat.Disturbancefromrenewableenergydevelopmentremainssmall,andlargelydueto
134ColoradoNaturalHeritageProgram©2015
concentratedwindturbine“farms”.Utility‐scalesolarinstallationshavethusfarbeenconfinedto
areasnearurbandevelopment,butthereisapotentialforfuturedisturbancefromthistypeof
facility,whichwouldrequireassociatedutilitycorridordevelopment.
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Sala,O.E.,andW.K.Lauenroth.1982.Smallrainfallevents:anecologicalroleinsemiaridregions.Oecologia53:301‐304.
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Shantz,H.L.1923.ThenaturalvegetationoftheGreatPlainsregion.AnnalsoftheAssociationofAmericanGeographers
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Sims,P.L.,andP.G.Risser.2000.Grasslands.In:Barbour,M.G.,andW.D.Billings,eds.,NorthAmericanTerrestrial
Vegetation,SecondEdition.CambridgeUniversityPress,NewYork,pp.323‐35
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stations.[website.]Availableat:http://www.wrcc.dri.edu/summary/Climsmco.html
Woodhouse,C.A.andJ.T.Overpeck.1998.2000yearsofdroughtvariabilityinthecentralUnitedStates.Bulletinofthe
AmericanMeteorologicalSociety79:2693‐2714.

136ColoradoNaturalHeritageProgram©2015
Riparian and Wetland
Table 2.8.Keyvulnerabilities,riparianandwetlandecosystems.
Habitat Climate factor(s) Consequences Other considerations
Riparian‐East Warmeranddrier
conditions,runoffamount
&timing
Earlierpeakflows,lowlate
summerflows,changein
relativespeciesabundance
Highlyaltereddueto
diversionsanddams,
agriculturallanduse
patterns
Riparian‐Mtn.Warmertemperatures,
runofftiming
Earlierpeakflows,lowlate
summerflows,changein
relativespeciesabundance
Connectivity
Riparian‐West Warmeranddrier
conditions,runoffamount
&timing
Earlierpeakflows,lowlate
summerflows,changein
relativespeciesabundance
Highlyaltereddueto
diversionsanddams,
agriculturallanduse
patterns
Wetland‐East Warmer,drierconditionsLowerwatertables,
reducedinput
Strictirrigationcontrol,
highlyaltered
Wetland‐Mtn.Warmertemperatures,
snowmelttiming
Potentialchangeinspecies
composition
Groundwater‐driventypes
morestable
Wetland‐West DrierconditionsLowerwatertables,
reducedinput
Highlyaltered
ClimateChangeVulnerabilityAssessmentforColoradoBLM137
RIPARIAN WOODLANDS AND SHRUBLANDS
Areasofgenerallywoodyvegetationassociatedwithmovingwaterandintermittentflooding
K.Carsey
extentexaggeratedfordisplay
Climate Vulnerability Ranks:
High (Eastern), Low (Mountain), Very High (Western)
Vulnerability summary
Key vulnerabilities:Warmeranddrierconditionsandtheconsequentchangeinrunoffamountand
timingareexpectedtoresultinearlierpeakflowsandlowlate‐summerflows,whicharelikelytoimpact
thestructureandspeciescompositionofriparianvegetation,especiallyatlowerelevations.
Riparianwoodlandandshrublandsoftheeasternplainsandwesternareasarerankedashaving
hightoveryhighvulnerabilitytotheeffectsofclimatechangebymid‐century,whilethoseofthe
mountainregionareconsideredtohavecomparativelylowvulnerability.Thevulnerabilityofsome
speciesassemblagesmaybehigherorlowerthanisreflectedbythecollectiveassessment.The
primaryfactorcontributingtotheserankingsisthedegreetowhichriparianwoodlandsatlower
elevationsareexpectedtoexperiencehighertemperatureswithoutcompensatoryprecipitation
increase.Thelowtomoderateresilienceranksreflectthehighlyalteredconditionofmostofthese
habitats,andingeneral,mostriparianwoodlandsandshrublandsthroughoutthestateshould
probablyberegardedashavingsomedegreeofvulnerabilitytoclimatechangethatisnotcaptured
byourbroad‐scaleassessmentmethods.
Distribution
Weassessedtheconditionofriparianwoodlandsandshrublandsineachofthreeregionsin
Colorado,correspondingroughlytoecoregionsasdefinedbyTheNatureConservancy(2009,
modifiedfromBailey1998):theeasternplains(CentralShortgrassPrairieecoregion);mountains
138ColoradoNaturalHeritageProgram©2015
(SouthernRockyMountainecoregion);andwesternplateausandvalleys(ColoradoPlateau,
WyomingBasins,andotherecoregions).
RiparianwoodlandsandshrublandsoccurthroughoutColorado.IneasternColoradotheyarefound
alongsmall,mediumandlargestreamsontheplains,includingthewidefloodplainsoftheSouth
PlatteandArkansasRivers.Montanetosubalpineriparianwoodlandsareseasonallyflooded
forestsandwoodlandsthroughouttheRockyMountains.Atmontanetosubalpineelevations,
riparianshrublandsmayoccurasnarrowbandsofshrubsliningstreambanksandalluvialterraces,
orasextensivewillowcarrsinbroadfloodplainsandsubalpinevalleys.Theyincludetheconifer
andaspenwoodlandsthatlinemontanestreams.Theyaremostoftenconfinedtospecific
streamsideenvironments,occurringonfloodplainsorterracesofriversandstreamsorinV‐
shaped,narrowvalleysandcanyons(wherethereiscold‐airdrainage).Lessfrequently,high
elevationriparianwoodlandsarefoundinmoderatetowidevalleybottoms,onlargefloodplains
alongbroad,meanderingrivers,andonpondorlakemargins.Theycanalsobefoundaroundseeps,
fens,andisolatedspringsonhillslopesawayfromvalleybottoms.Atlowerelevationsonthe
westernslope,riparianwoodlandsandshrublandsarefoundwithinthefloodzoneofrivers,on
islands,sandorcobblebars,andimmediatestreambanks.Theyoftenoccurasamosaicofmultiple
communitiesthataretree‐dominatedwithadiverseshrubcomponent.
Characteristic species
Ontheeasternplains,riparianwoodlandsandshrublandsaregenerallydominatedbyplains
cottonwood(Populusdeltoides)andwillow(Salixspp.),butalsooccurasamosaicofmultiple
communitiesinterspersedwithherbaceouspatches.
Dominantshrubswithinthemontanetosubalpineelevationzoneincludealder(Alnustenuifolia),
birch(Betulaoccidentalis),dogwood(Cornussericea),andwillowspecies.Generallytheupland
communitiessurroundingtheseripariansystemsareeitherconiferoraspenforests.
Westernriparianforestsaretypicallydominatedbycottonwood(Populusangustifolia,P.deltoides)
andwillow,butmayincludemaple(Acerglabrum),Douglasfir(Pseudotsugamenziesii),spruce
(Piceaspp.),andjuniper(Juniperusspp.).Shrublandsareprimarilydominatedbywillow,alder,and
birch.
Environment
RiparianareasofColorado’seasternplainsareprimarilyassociatedwithintermittentlyflowing
streamsofsmalltomoderatesize,butalsoincludethelargerfloodplainsofthelargesnowmelt‐fed
rivers(SouthPlatteandArkansas).Smallerstreamsreceivewaterfromprecipitationand
groundwaterinflow,havegreaterseasonalflowvariationthanthelargerrivers,andhaveminimal
ornoflowexceptduringfloods(Covichetal.1997).InmountainousareasofColorado,riparian
areasaremuchmorelikelytobeassociatedwithperenniallyflowingstreams,andtheseplant
communitiesareadaptedtohighwatertablesandperiodicflooding.Runoffandseepagefrom
snowmeltisaprimarysourceofstreamflow.LowerelevationriparianareasinwesternColorado
areadaptedtoperiodicflooddisturbanceandpredominantlyaridconditions.Largerstreamsand
riversaresustainedbyrunofffrommountainareas.Smallerstreamsareprimarilysupportedby
ClimateChangeVulnerabilityAssessmentforColoradoBLM139
groundwaterinflow,oroccasionallargeprecipitationevents,andareoftendryforsomeportionof
theyear.
Dynamics
Riparianwoodlandsaretolerantofperiodicfloodingandhighwatertables.Snowmeltmoisturein
thissystemmaycreateshallowwatertablesorseepsforaportionofthegrowingseason.
Manyhigherelevationriparianshrublandsareassociatedwithbeaver(Castorcanadensis)activity,
whichcanbeimportantformaintainingthehealthoftheriparianecosystem(historicallythis
wouldhavebeentrueforlowerelevationstreamsaswell).Beaverdamsabatechanneldown
cutting,bankerosion,anddownstreammovementofsediment.Beaverdamsalsoraisethewater
tableacrossthefloodplainandprovideyear‐roundsaturatedsoils.Plantestablishmentand
sedimentbuild‐upbehindbeaverdamsraisesthechannelbedandcreatesawetlandenvironment.
Hydrologically,smallerriverstendtohavegreaterseasonalvariationinwaterlevelswithless
developedfloodplainthanthelargerrivers,andcandrydowncompletelyforsomeportionofthe
year.Cottonwooddie‐offsrelatedtoprolonged,intensedroughtandhydrologicalalterationshave
affectedsomestands.
Lowerelevationriparianwoodlandsandshrublandsaredependentonanaturalhydrologicregime,
especiallyannualtoepisodicflooding.Thesewoodlandsandshrublandsgrowwithinacontinually
changingalluvialenvironmentduetotheebbandflowoftheriver,andriparianvegetationis
constantlybeing“re‐set”byfloodingdisturbance.Insomeareas,Russianolive(Elaeagnus
angustifolia),tamarisk(Tamarixspp.),andotherexoticspeciesarecommon.
CCVA Scoring
Exposure‐Sensitivity (Potential Impact) Ranks
EasternMountainWestern
PercentColoradoacreswithprojectedtemp>
max&pptdelta<5%55.5%1.8%37.2%
InitialExposure‐SensitivityRankHighLowHigh
PercentColoradoacreswithtemp<=max&ppt
delta<5%morethan50%?No(6.7%)No(25.3%)No(14.7%)
FinalExposure‐SensitivityRankHighLow High
Exposuretotemperaturechange
Underprojectedmid‐centurytemperatures,about60%ofthecurrentrangeofriparianwoodland
andshrublandineasternColoradowouldexperienceannualmeantemperaturesabovethecurrent
statewidemaximum.Theproportionissimilar(54%)forwesternriparianareas,butmuchlower
(2%)inmountainareas.
140ColoradoNaturalHeritageProgram©2015
Exposuretoprecipitationchange
About62%ofriparianwoodlandandshrublandineasternColoradowillbeexposedtoeffectively
drierconditionsevenunderunchangedorslightlyincreasedprecipitationprojectedformid‐
century.Forwesternriparianareas,theproportionisslightlylower(52%),andmountainriparian
areascanexpecttoseeeffectivelydrierconditionsinabout27%oftheirdistribution.
Sensitivityofecosystemtotemperatureandprecipitation
Riparianwoodlandsandshrublandsareadjacenttoandaffectedbysurfaceorgroundwaterof
perennialorephemeralwaterbodies.Theyarecharacterizedbyintermittentfloodinganda
seasonallyhighwatertable.Thecloseassociationofriparianareaswithstreamflowandaquatic
habitatsmeansthatchangingpatternsofprecipitationandrunoffthatalterhydrologicregimesare
likelytohaveadirecteffectonthesehabitats(Caponetal.2013).Inaddition,theinteractionof
increasedgrowthduetoincreasedCO2concentration,warming‐induceddrought,andheat‐stress
withpotentiallyreducedstreamflowsarelikelytoaffectripariancommunitystructureand
composition,especiallyinmorearidareas(Perryetal.2012).
Climateprojectionsformid‐centuryaregenerallyforwarmeranddrieroutcomes,although
precipitationchangeismoreuncertainindirectionandmagnitude(Lucasetal.2014).Annual
runoffandstreamflowareaffectedbybothtemperatureandprecipitation,andeffectsoffuture
changesinthesefactorsaredifficulttoseparate.Warming‐inducedchangesinsnowpackand
snowmelttimingincludeearlierspringsnowmelt,ashifttowardsprecipitationfallingasrain
insteadofsnowinspringandfall,andincreasedsublimationfromthesnowpackthroughoutthe
season.Thesechangesareexpectedtohavegreaterimpactatlowerelevations(Lucasetal.2014).
Theeffectsofwarmingtemperaturesarelikelytochangethehydrologiccyclebyshiftingrunoffand
peakflowstoearlierinthespring,andreducinglatesummer‐earlyautumnflows(Roodetal.
2008).Riparianvegetationisinpartdeterminedbyflowlevels(Aubleetal.1994).Reduced
summerflowsarepredictedtoresultinmorefrequentdroughtstressforriparianhabitats,witha
resultinglossorcontractionofthehabitat(Roodetal.2008).
Resilience and Adaptive Capacity Ranks
EasternOverallScore: 0.52Rank:Moderate
MountainOverallScore:0.60Rank:Moderate
WesternOverallScore:0.49Rank:Low
Bioclimaticenvelopeandrange
Scores:0.57(Eastern),0.81(Mountain),0.66(Western)
Theseshrublandsarenotlimitedtohighelevations,andinColoradoarewellwithintherangeof
continentaldistribution.Lowerelevationtypesoftheeastandwestslopehavesomewhatnarrower
bioclimaticrangesthanmontanetypes.
Growthformandintrinsicdispersalrate
Score:0.5
ClimateChangeVulnerabilityAssessmentforColoradoBLM141
Themixedgrowth‐forms(trees,shrubs,andherbaceous)thatmaybedominantorcharacteristicof
theseecosystemsgivesthemanintermediateresiliencescoreinthiscategory.
Vulnerabilitytoincreasedattackbybiologicalstressors
Scores:0.5
Seedingwithnon‐nativepasturegrasses,invasionbytamariskandexoticforbshasalreadyaltered
speciescompositioninmanyeasternandwesternriparianecosystem,andwillhavealastingeffect.
Invasivespecieswiththepotentialtoalterecosystemfunction(e.g.,tamarisk)areanongoing
managementchallenge.
Forhigherelevationriparianhabitats,invasivespeciesandgrazingareminorimpacts(Chimneret
al.2010),butthesefactorsareanongoingsourceofdisturbanceinlowermontaneriparianareas.
Manyofthesecommunitieshavedegradedunderstories,withweedyherbaceouslayersand
Russianoliveandtamariskinvadingtheshrublayers.
Vulnerabilitytoincreasedfrequencyorintensityofextremeevents
Scores:0.5
Increasedfrequencyandmagnitudeofdroughtislikelytohavesignificantimpactonthesehabitats.
Althoughfirehasoftennotbeenconsideredanimportantdisturbanceinwetlandandriparian
areas,recentevidencesuggeststhatfiresinmosttypesofadjacentuplandvegetationarelikelyto
burnintothesehabitatsaswell(CharronandJohnson2006,StrombergandRychener2010).
Otherindirecteffectsofnon‐climatestressors–landscapecondition
EasternPlainsScore:0.44
RiparianhabitatsofColorado’seasternplainscontinuetobethreatenedbyurban,exurban,and
recreationaldevelopmentaswellasagriculturalactivities(e.g.,tillageandcropproduction,
livestockgrazing,concentratedanimalfeedingoperations)inadjacentuplandswhoseeffects
contributetoagraduallossofhabitatareaandquality.Landusewithintheriparianareaaswellas
inadjacentanduplandareascanfragmentthelandscapeandreduceconnectivitybetweenriparian
patchesandbetweenripariananduplandareas,adverselyaffectingthemovementofsurface/
groundwater,nutrients,anddispersalofplantsandanimals.Roads,bridges,anddevelopmentcan
alsofragmentbothripariananduplandareas.Gravelminingisanadditionalsourceofdisturbance
tothesehabitats,especiallyalongthelargerrivers.
Alterationofnaturalhydrologicalprocessesbydams,diversions,ditches,roads,etc.,andabiotic
resourceconsumptionthroughgroundwaterpumpinghaveconsiderablyalteredthepresettlement
conditionofthesehabitats,andareanongoingthreat.Dams,reservoirs,diversions,ditchesand
otherhumanlandusesalterthenaturalflowregimeofastream,andcandisrupttheecological
integrityoftheripariansystem.Physicalchangesresultingfromalteredflowregimesinclude
downstreamerosionandchannelization,reducedchannelmorphologydynamics,reducedbase
and/orpeakflows,lowerwatertablesinfloodplains,andreducedsedimentdepositioninthe
floodplain(Poffetal.1997).Mosthydrologicalalterationisduetoagriculturalneeds,exceptin
142ColoradoNaturalHeritageProgram©2015
highlydevelopedareasalongthemountainfrontwhereotherusesareovertakingagriculturaluse.
ContinuedgroundwaterpumpingfromtheOgallala‐HighPlainsaquiferhasloweredthewatertable
suchthatmanyformerlyflowingstreamsarenowdryformuchoftheyear(Dodds1997).Flood
controlcangreatlyreducethespatialcomplexityofriparianandwetlandhabitat.
MountainScore:0.69
Riparianareasinmountainareasaregenerallyingoodcondition,althoughnotwithoutimpactfrom
anthropogenicdisturbance.Threatstoriparianwoodlandandshrublandinmountainareasof
Coloradovarywithelevation.Additionalfragmentationandlossofriparianhabitatsatlower
elevationinmountainousareasofColoradoduetourbanizationandagricultureisanongoing
threatinmanyareas.Athigherelevationswherelandsareinpublicownershipthesehabitatsare
mostthreatenedbyrecreationaldevelopmentandusewhereroadsprovideaccessandareasource
ofsedimentationandpollutantrunoff.Exceptatthehighestelevations,fewmountainriparian
habitatsarewithouthydrologicalmodification,andtheongoingstressesfromreservoirs,dams,
diversions,andsimilaralterationsincludedownstreamerosionandchannelization,reduced
channelmorphologydynamics,reducedbaseand/orpeakflows,lowerwatertablesinfloodplains,
andreducedsedimentdepositioninthefloodplain(Poffetal.1997).
WesternSlopeScore:0.40
RiparianareasinwesternColoradoaregenerallyinfaircondition,andhavebeenheavilyimpacted
byanthropogenicdisturbanceinmanyareas.Threatstoriparianhabitatsfromongoingurbanand
exurbandevelopmentaregenerallylessinmostareasofColorado’swestslopeincomparisonwith
theFrontRange,butnotabsent.Agriculturalactivitiesareubiquitousinlowerelevationriparian
habitats,includingirrigatedtilledanduntilledcrops,anddomesticlivestockgrazing.Gravelmining
iscommonalongthelargerrivers.Thesedisturbancesarelikelytocontinuetoproduceagradual
reductioninhabitatareaandqualityinwestsloperiparianhabitats.
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Perspective.JournaloftheNorthAmericanBenthologicalSociety,16:162‐168.
Holsinger,L.,R.E.Keane,D.J.Isaak,L.Eby,andM.K.Young.2014.Relativeeffectsofclimatechangeandwildfireson
streamtemperatures:asimulationmodelingapproachinarockyMountainwatershed.ClimaticChange124:191‐206.
Lucas,J.,J.Barsugli,N.Doesken,I.Rangwala,andK.Wolter.2014.ClimateChangeinColorado:asynthesistosupport
waterresourcesmanagementandadaptation.Secondedition.ReportfortheColoradoWaterConservationBoard.
WesternWaterAssessment,CooperativeInstituteforResearchinEnvironmentalSciences(CIRES),UniversityofColorado
Boulder.
Perry,L.G.,D.C.Andersen,L.V.Reynolds,S.M.Nelson,andP.B.Shafroth.2012.Vulnerabilityofriparianecosystemsto
elevatedCO2andclimatechangeinaridandsemiaridwesternNorthAmerica.GlobalChangeBiology18:8221‐842.
Poff,N.L.,M.M.Brinson,andJ.W.Day.2002.Aquaticecosystemsandglobalclimatechange:potentialimpactsoninland
freshwaterandcoastalwetlandecosystemsintheUnitedStates.PreparedforthePewCenteronGlobalClimateChange.
Available:http://www.c2es.org/publications/aquatic‐ecosystems‐and‐climate‐change
Rood,S.B.,J.Pan,K.M.Gill,C.G.Franks,G.M.Samuelson,andA.Shepherd.2008.DecliningsummerflowsofRocky
Mountainrivers:changingseasonalhydrologyandprobableimpactsonfloodplainforests.JournalofHydrology349:397‐
410.
Stromberg,J.C.andT.J.Rycheneer.2010.Effectsoffireonriparianforestsalongafree‐flowingdrylandriver.Wetlands
30:75‐86.
TheNatureConservancy[TNC].2009.TerrestrialEcoregionsoftheWorld,digitalvectordata.TheNatureConservancy,
Arlington,Virginia.
144ColoradoNaturalHeritageProgram©2015
WETLANDS
Herbaceousvegetationdominatedareascharacterizedbywatersaturationandhydricsoils
G.Doyle
extentexaggeratedfordisplay
Climate Vulnerability Ranks:
High (Eastern), Moderate (Mountain and Western)
Vulnerability summary
Key vulnerabilities:Warmeranddrierconditionsforlowerelevationwetlandsarelikelytoresultin
reducedinputstothesehabitats,andlowergroundwaterlevelsingeneralthatmayreducetheextent
anddegradetheconditionofwetlands.Inhigherelevationswarmertemperaturesandconsequent
earliersnowmeltmayinfluencethespeciescompositionofwetlandhabitats.Ground‐waterdependent
wetlandsathigherelevationsareexpectedtobesomewhatbufferedfromhydrologicchange.
Wetlandhabitatsofthewesternvalleysandmountainareasarerankedashavingmoderate
vulnerabilitytotheeffectsofclimatechangebymid‐century,whilethoseoftheeasternplainsare
consideredhighlyvulnerable.Theprimaryfactorcontributingtothehigherrankingforeastern
plainswetlandsisthedegreeofincreasedtemperatureprojectedforthatregion,incomparison
withtheotherregions.Thevulnerabilityofsomespeciesassemblagesmaybehigherthanis
reflectedbythecollectiveassessment.Themoderateresilienceranksreflectthehighlyaltered
conditionofmostofthesehabitats,andingeneral,allwetlandsthroughoutthestateshould
probablyberegardedashavingsomedegreeofvulnerabilitytoclimatechangethatisnotcaptured
byourbroad‐scaleassessmentmethods.
Distribution
Weassessedtheconditionofnon‐riparianwetlandsineachofthreesectionsofColorado,
correspondingapproximatelytoecoregionsasdefinedbyTheNatureConservancy(2009,modified
fromBailey1998):theeasternplains(CentralShortgrassPrairieecoregion);mountains(Southern
ClimateChangeVulnerabilityAssessmentforColoradoBLM145
RockyMountainecoregion);andwesternplateausandvalleys(ColoradoPlateau,WyomingBasins,
andotherecoregions).Asconsideredherein,wetlandsareareascharacterizedbywatersaturation
andhydricsoilstypicallysupportinghydrophyticvegetation.
InColorado,non‐riparianwetlandhabitatsincludemoisttowetmeadows,emergentmarshes,fens,
andseepsandsprings.Non‐riparianwetlandsofColorado’seasternplainsandwesternvalleysare
primarilymarshes,seepsandsprings,andwetmeadows.Playas(shallow,temporarywetlands)are
scatteredthroughouttheeasternplains,andoccurinlimiteddistributiononthewesternslopeas
well.Althoughnaturalmarshesandwetmeadowsareprimarilyfoundathigherelevations,
irrigationpractices(directfloodapplication,irrigationtailwaters,elevatedgroundwaterlevels,
etc.)havegreatlyincreasedtheincidenceofwetmeadowsontheeasternplains(Sueltenfussetal.
2013).Mostofthestate’swetmeadowsoccurinmountainousareasofColorado,andmarshesare
generallylesscommon.Fensarealsocharacteristicofthemountainregion.
Characteristic species
Naturalwetmeadowsaredominatedbynativesedgesandgrasses,whilethoseinfluencedby
irrigationmaybedominatedbynon‐nativepasturegrasses.Seepsandspringshavegenerally
similarvegetationtowetmeadows.
Standingwaterinemergentmarshesrestrictsthedominantspeciestorobustwetlandplants,such
ascattail(Typha),bulrush(ScirpusandSchoenoplectusspp.),andlargesedges(Carexspp.).Atlower
elevations,marshescanbecomedenselyvegetatediftheyarenotperiodicallyflushedby
floodwaterormechanicalthinning.
Fenvegetationisgenerallycharacterizedbyadensecoverofsedgesandmoss,oftenintermixed
withforbsandshorttodwarfshrubssuchaswillowandbogbirch(Betulanana).
Environment
MeadowsoccurthroughoutColorado,butmostnaturalwetmeadowsarefoundwithinthemontane
tosubalpinezone.Naturalwetmeadowsaretightlyassociatedwithsnowmeltorsubsurface
groundwaterdischargeandtypicallynotsubjectedtohighdisturbanceeventssuchasflooding.
Withinmountainvalleysandatlowerelevations,extensiveacresofwetmeadowsarealsolinkedto
irrigationpractices,includingfloodirrigationandseepagefromirrigationditches.
Emergentmarshesarewetlandsthatexperiencefrequentorprolongedponding.Marshesoccurin
depressionsandkettleponds,asfringesaroundlakes,alongstreamsandrivers,andbehindmany
typesofimpoundments.Theycanbefoundatallelevations,butaremorecommonatmidtolower
elevations.
Fensarewetlandswiththickorganicsoilsthataresupportedbystablegroundwaterdischarge.
Fensaretypicallyfoundwithinthemontanetosubalpinezone,generallyabove7,000ft.,andcan
formalongtheedgesofvalleybottoms,atbreaksinslope,aroundhillslopeseeps,inshallowbasins
oranywherewheresufficientgroundwateremergestoperenniallysaturatesoils.Fensare
146ColoradoNaturalHeritageProgram©2015
considered“oldgrowth”wetlands,astheaccumulationofthickorganicsoilscantakethousandsof
years.
Seepsandspringsincludesmallwetlandsthatarehydrologicallysupportedbygroundwater
discharge.TheyarefoundthroughoutColoradoandcanbeacomponentofthepreviously
describedwetlandtypes,butaremostnotablewithinthecliffandcanyoncountryoftheColorado
PlateauandtheLowerArkansasbasin.
Dynamics
Hydrologyistheprimarydeterminantofthedevelopmentandpersistenceofwetlandecosystems,
andvariationsintiminganddurationofinundationlargelydeterminethetypeofwetland.The
waterbudgetorhydroperiodofawetlandincludesprecipitation,evapotranspiration,andboth
surfaceflowandgroundwater.Althoughwatermaynotbecontinuouslypresentinwetlands,asa
generalruleofthumbinundationduringatleast14consecutivegrowingseasondaysissufficientto
exertasignificantinfluenceonwetlandprocesses(CulverandLemly2013).
CCVA Scoring
Exposure‐Sensitivity (Potential Impact) Rank
EasternMountainWestern
PercentColoradoacreswithprojectedtemp>
max&pptdelta<5%37.2%0.8%15.3%
InitialExposure‐SensitivityRankHighLowModerate
PercentColoradoacreswithtemp<=max&ppt
delta<5%morethan50%?No(11.3%)Yes(54.5%)No(43.5%)
FinalExposure‐SensitivityRankHighModerate Moderate
Exposuretotemperaturechange
Underprojectedmid‐centurytemperatures,about43%ofthecurrentrangeofwetlandecosystem
ineasternColoradowouldexperienceannualmeantemperaturesabovethecurrentstatewide
maximum.Theproportionislower(19%)forwesternwetlands,andquitelow(1%)inmountain
areas.
Exposuretoprecipitationchange
About49%ofwetlandhabitatsineasternColoradowillbeexposedtoeffectivelydrierconditions
evenunderunchangedorslightlyincreasedprecipitationprojectedformid‐century.Forwestern
wetlandecosystems,theproportionissomewhathigher(59%),andmountainwetlandscanalso
expecttoseeeffectivelydrierconditionsinabout55%oftheirdistribution.
Sensitivityofecosystemtotemperatureandprecipitation
Bothtemperatureandprecipitationcanaffectthepresenceandextentofwetlandsonthe
landscape.Warmer,drierconditionsarelikelytoleadtolowergroundwaterlevels,atleastduring
certainseasons,andcanhaveanegativeimpactontheseecosystems.Earlierspringrun‐offwould
ClimateChangeVulnerabilityAssessmentforColoradoBLM147
resultindryingconditionsbylatesummer,possiblyreducingthesizeofexistingwetlands.
Similarly,wetlandscurrentlysupportedbylate‐meltingsnowfieldsarelikelytodrysoonerthan
undercurrentconditions.
Effectsofclimatechangeonwetlandsareexpectedtobelargelymediatedthroughthesourceof
water,eitherprecipitation,groundwaterdischarge,or,forwetlandsassociatedwithriparianareas,
surfaceflow(Winter2000).Precipitationsupportedwetlandsarethoughttobemostvulnerableto
drierclimaticoutcomes,butdecreasingprecipitationwouldalsobelikelytolowerwatertable
levelsandleadtocontractionofgroundwater‐fedwetlands(Winter2000,Poffetal.2002).Under
wetterconditions,somewetlandtypesmaybeabletoexpandoratleastmaintaincurrentextents.
Considerationoftheeffectsofchangingprecipitationisfurthercomplicatedbythefactthat
wetlandsmayreceivewaterinputfromthesurroundingbasin,notjusttheimmediateenvirons
(Gitayetal.2001).
Temperatureaffectswetlanddistributionandfunctionprimarilythroughitseffectsonratesof
chemical,physicalandbiologicalprocesses(GageandCooper2007).Althoughwetlandsareto
someextentbufferedfromtheimmediateeffectsofwarmingonwatertemperature,warmingcould
increasebothplantgrowthandmicrobialactivitydrivingdecomposition(Fischlinetal.2007).
Temperatureisalsoadriverofevapotranspirationrate,andthewatercycleingeneral(Gitayetal.
2001).
Variationinclimaticconditionsaffectsgroundwaterlevelsbothdirectlyviarechargerates,and
indirectlythroughchangesinpatternsofgroundwateruse,especiallyirrigation(Tayloretal.2012).
Drierfutureconditionsarelikelytoresultintightercontrolsonirrigationseepage,anda
consequentreductioninwetlandacressupportedbythissource.Althoughclimatechangeis
expectedtohaveasignificanteffectonwetlandsthroughchangesintheseasonalityandvariability
ofprecipitationandextremeevents(Gitayetal.2005),changingwaterusepatternsinresponseto
climatechangearealsolikelytoplayamajorroleinthefutureofwetlands(Tayloretal.2012).
Resilience and Adaptive Capacity Rank
EasternOverallScore: 0.52Rank:Moderate
MountainOverallScore:0.59Rank:Moderate
WesternOverallScore:0.52Rank:Moderate
Bioclimaticenvelopeandrange
Scores:0.66(Eastern),0.77(Mountain),0.69(Western)
Mostwetlandsarenotlimitedtohighelevations,andinColoradoarewellwithintherangeof
continentaldistribution.Lowerelevationtypesoftheeastandwestslopehavesomewhatnarrower
bioclimaticrangesthanmontanetypes.
Growthformandintrinsicdispersalrate
Score:0.5
148ColoradoNaturalHeritageProgram©2015
Thisecosystemisdominatedbyrelativelyfastgrowinggraminoidandherbaceousspecies,butmay
berestrictedindispersalabilityifhabitatsareisolatedwithinthelandscape.
Vulnerabilitytoincreasedattackbybiologicalstressors
Scores:0.5
Forhigherelevationwetlands,invasivespeciesandgrazingareminorimpacts(Chimneretal.
2010),butthesefactorsareanongoingsourceofdisturbanceinlowerelevationwetlandsthat
lowertheresilienceoftheseoccurrences.Invasivespecieswiththepotentialtoalterecosystem
functionareanongoingmanagementchallenge.Impactedwetlandsmaybemorevulnerableto
invasionbyexoticspecies.
Vulnerabilitytoincreasedfrequencyorintensityofextremeevents
Scores:0.5
Increasedfrequencyandmagnitudeofdroughtislikelytohavesignificantimpactonthesehabitats.
Eventualimpactsofclimatechangeonaquifersourceofwatercouldeventuallyeliminatesome
types(seeps)fromsomeareas.
Otherindirecteffectsofnon‐climatestressors–landscapecondition
EasternPlainsScore:0.43
WetlandsofColorado’seasternplainscontinuetobethreatenedbyurbanandexurban
developmentaswellasagriculturalactivities(e.g.,tillageandcropproduction,livestockgrazing,
concentratedanimalfeedingoperations)inadjacentuplandswhoseeffectscontributetoagradual
lossofhabitatareaandquality.Theincidentalcreationofwetlandsthroughwatermanagement
activitiesisgenerallynotsufficienttocompensateforlossesinthisecosystem.
MountainScore:0.67
WiththeexceptionoftheextensivewetlandsoftheSanLuisValley,wherewaterdevelopmentfor
agriculturaluseisextensive,wetlandhabitatsinmountainareasofColoradoaregenerallyingood
condition,withfeweranthropogenicimpacts,andareoveralllessthreatenedbydevelopmentand
agriculturethanthoseinlowerelevationsofthestate.
WesternSlopeScore:0.41
WetlandhabitatsinwesternColoradohavebeenheavilyimpactedbyanthropogenicactivities,and
areofteninonlyfaircondition.Alteredhydrologyduetodams,diversions,andgroundwater
pumpingmayinteractwithwarmingtemperaturesandchangesinprecipitationpatterntoalter
groundwaterrechargerates,andleadtodryingorcontractionofwetlands.Hanginggardensarean
especiallyfragilewetlandtypeofthewesternslope.Wheretheyareaccessibletofoottrafficor
livestock,erosion,trampling,andintroductionofexoticspeciesareanongoingthreat.
ClimateChangeVulnerabilityAssessmentforColoradoBLM149
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Bailey,R.1998.EcoregionsmapofNorthAmerica:Explanatorynote.USDAForestService,Misc.Publicationno.1548.10
pp.+mapscale1:15,000,000
Culver,D.R.andJ.M.Lemly.2013.FieldGuidetoColorado’sWetlandPlants:Identification,EcologyandConservation.
ColoradoNaturalHeritageProgram,WarnerCollegeofNaturalResources,ColoradoStateUniversity,FortCollins,
Colorado.
Fischlin,A.,G.F.Midgley,J.T.Price,R.Leemans,B.Gopal,C.Turley,M.D.A.Rounsevell,O.P.Dube,J.Tarazona,A.A.Velichko.
2007.Ecosystems,theirproperties,goods,andservices.ClimateChange2007:Impacts,AdaptationandVulnerability.
ContributionofWorkingGroupIItotheFourthAssessmentReportoftheIntergovernmentalPanelonClimateChange,
M.L.Parry,O.F.Canziani,J.P.Palutikof,P.J.vanderLindenandC.E.Hanson,Eds.,CambridgeUniversityPress,Cambridge,
211‐272.
Gage,E.,andD.J.Cooper.2007.Historicrangeofvariationassessmentforwetlandandriparianecosystems,U.S.Forest
ServiceRegion2.PreparedforUSDAForestService,RockyMountainRegion.DepartmentofForest,Rangelandand
WatershedStewardship,ColoradoStateUniversity,FortCollins,Colorado.
Gitay,H.,A.SuarezandR.T.Watson.2002.ClimateChangeandBiodiversity.IPCCTechnicalPaper,Intergovernmental
PanelonClimateChange,Geneva,77pp.
Gitay,H.,S.Brown,W.EasterlingandB.Jallow.2001.Ecosystemsandtheirgoodsandservices.ClimateChange2001:
Impacts,Adaptation,andVulnerability.ContributionofWorkingGroupIItotheThirdAssessmentReportofthe
IntergovernmentalPanelonClimateChange,J.J.McCarthy,O.F.Canziani,N.A.Leary,D.J.DokkenandK.S.White,Eds.,
CambridgeUniversityPress,Cambridge,237‐342.
Poff,N.L.,M.M.Brinson,andJ.W.Day.2002.Aquaticecosystemsandglobalclimatechange:potentialimpactsoninland
freshwaterandcoastalwetlandecosystemsintheUnitedStates.PreparedforthePewCenteronGlobalClimateChange.
Available:http://www.c2es.org/publications/aquatic‐ecosystems‐and‐climate‐change
Sueltenfuss,J.P.,D.J.Cooper,R.L.Knight,andR.M.Waskom.2013.Thecreationandmaintenanceofwetlandecosystems
fromirrigationcanalandreservoirseepageinasemi‐aridlandscape.Wetlands33:799‐810.
Taylor,R.G.,B.Scanlon,P.Dölletal.2012.Groundwaterandclimatechange.NatureClimateChange3:322‐329.
TheNatureConservancy[TNC].2009.TerrestrialEcoregionsoftheWorld,digitalvectordata.TheNatureConservancy,
Arlington,Virginia.
Winter,T.C.2000.Thevulnerabilityofwetlandstoclimatechange:ahydrologiclandscapeperspective.Journalofthe
AmericanWaterResourcesAssociation.36:305‐311.
150ColoradoNaturalHeritageProgram©2015
FRESHWATER ECOSYSTEMS – METHODS
InconsultationwithBLM,CNHPidentifiedsixfreshwaterecosystemgroupstobeassessed(Table
2.9).Ouranalysisevaluatedtheassociatedwetlandandriparianecosystemsseparately,sothat
vulnerabilityresultsherearenotnecessarilytiedtotheassessmentspresentedabove.
Table 2.9.Freshwaterecosystemtargets.
Freshwater Ecosystems
Streams–highelevation(>6,500ft)coldwaterRivers
Streams–midelevation(<6,500ft)coolandwarmerwaterLakes
CooltocoldwatertransitionalstreamareasReservoirs
Thevulnerabilityoffreshwaterecosystemstoclimatechangebymid‐centurywasevaluated
throughacombinationofspatialandnarrativemethods.Theprimarymethodofspatialevaluation
isbasedonamodelofprojectedchangeinwatertemperaturearoundacoldtocool‐waterfisheries
transitionline.
Transition line model
STORETwatertemperaturedatawithinColoradoweredownloadedfromtheEPAwebsite.Sample
datesrangedfrom1964to2013duringalltimesofyearandday.Thenumberofdatarecordsper
stationrangesfrom1tonearly2,000.Julywasassumedtobethecriticalmonthduringwhichwater
temperaturesreaching68°F(20°C)couldnegativelyimpactcoldwaterfishes.Fromthefulldataset
(68,948records),7,373datapointsfrom1,413stationsweretakenduringthemonthofJuly,
rangingover1964‐1984.Julysamplestationsarenotevenlydistributedacrossthestate,with
relativelyfewacrosstheeasternplainsandneartheWyomingborder,andwithgenerallyclumped
spacing(Figure2.10).
MultipleJulydatarecordsforasinglestationwereaveraged.MeanJulywatertemperatureper
stationrangedfrom33.8‐87.1°F(1‐30.6°C).
A2‐power,cross‐validatedlocalpolynomialinterpolationwascalculatedonthemeanJulywater
temperaturestoderivewatertemperaturecontourlinesacrossthestate.Temperaturevalueswere
weightedbynumberofsamplerecordsperstation,togivehigherweighttothemorecertainvalues.
Notsurprisingly,modelfitwaspoorinthoseareaswithfewdatapoints,butwasexcellenttogood
inthoseareasmostlikelytorepresentthetemperaturetransitionline(Figure2.11),sowedeemed
themodelacceptableforthecurrentpurpose.
ClimateChangeVulnerabilityAssessmentforColoradoBLM151

Figure 2.10.STORETstationswithJulywatertemperaturereadings.
Figure 2.11.PredictionStandardError.
152ColoradoNaturalHeritageProgram©2015
AfilledcontourforJulywatertemperaturesbetween67‐69°F(19.5‐20.5°C)wasgeneratedfrom
thelocalpolynomialinterpolationpredictionsurface(Figure2.12).Projectedfuturetemperatureis
availableassurfaceairtemperature,andthereisnotaone‐to‐onerelationshipbetweenairand
watertemperaturesoverColorado'scomplextopographical,elevational,andlatitudinalranges.To
accountfornorth‐southandeast‐westgradientsintranslatingthewatertemperaturecontourtoair
temperature,wedividedthestateintosixequalsections.Foreachoffoursections(thetwoeastern
sectionswerenotusedduetolackofdata)wecalculatedthemeanandstandarddeviationofthe
currentmeanJulyairtemperatureforeachwatertemperaturecontoursegmentwithinthesection
(theSouth‐CentralsectionhastwoseparatecontourstodistinguishtheconditionswithintheSan
LuisValley(Figure2.12).
Figure 2.12.Interpolatedwatertemperature67‐69°Ffilledcontour,splitintoNorth‐West,North‐Central,South‐
West,andSouth‐Centralsections.ColorsrepresentthemeanJulyairtemperaturecoincidingwitheachcontour
section.
Eachfilledcontoursectionisnotasinglelinebutanarea.Airtemperaturesbelowthemeancanbe
thoughtofasrepresentingthe"leading"edgeofthetransitionbetweencoldandcool‐water
fisheries,whilevaluesabovethemeanwouldrepresentthe"trailing"edgeforthetransitionfrom
cooltowarm‐waterfisheries.Ouranalysisfocusedonmeanvalues(Table2.10)asthebest
representationoftheoveralltransitionarea.
Foreachcontoursegmentshownabove(NW,NC,SW,SC,andtheSanLuisValley),wegenerateda
contourofthecurrentJulyairtemperaturemeanvalue(tablecolumnshadedinblue).Thesefive
sectionalcontourswerethenmanuallystitchedtogetherintoasinglecohesivetemperature
ClimateChangeVulnerabilityAssessmentforColoradoBLM153
contourforthestate,representingthecurrentcoldtowarm‐waterfisheriestransitionline.The
sameprocedurewasfollowedtocreateprojectedfuturetransitionlinesforRCP4.5andRCP8.5
(Figure2.13).ThevulnerabilityanalysiswasmadebycomparingthecurrentandRCP8.5lines,to
maintainconsistencywiththeterrestrialecosystemevaluation.Notethat,becauseweareusingair
temperatureasaproxyforwatertemperature,cold‐waterreleasesfromreservoirstoragearenot
accountedforinthemodel.
Table 2.10.Meanandstandarddeviation(STD)currentJulyairtemperature(°F)valuesforeachcontoursegment
withinasection.Valuesinparenthesesare°C.
Section Mean STD
SC,valley63.4(17.4)2.78(1.55)
NW66.7(19.3)3.61(2.00)
SC,east68.6(20.3)4.76(2.64)
SW69.6(20.9)3.49(1.94)
NC69.8(21.0)3.13(1.74)
Themodeledtransitionlinewasusedtoassignstreamandriverreachestocold,transitional,or
warmwatercategories.Transitionalreachesarethoselyingwithinapproximately0.5kmoneither
sideofthetransitionline;exactdistancesaresomewhatvariabledependingonlocalstream
morphologyandreachsegmentlength.
Exposuretoclimatechangewasevaluatedbycomparingthetotalstreamlengthcurrentlyfallingin
eachcategorywiththetotalsunderprojectedmid‐centuryconditions.Percentchangebetween
categoriesissummarizedbyregion(Eastern,Mountain,Western),usingthesamedivisionsthat
wereappliedtowetlandandriparianecosystems.
Tofocusthevulnerabilityanalysisonthelossofcoldwaterandtransitionalreaches,weuseda
decision‐treebasedoncurrentandprojectedstreamlengthsinthesecategoriestoassignexposure
ranksforstreamsandrivers(Figure2.14).Vulnerabilityishighestinregionswherecurrently
existingcoldwaterandtransitionalreachesareessentiallyentirelyeliminated.Inregionswhere
currentpresenceofcoldortransitionalreachesisalreadyverylow,vulnerabilityismoderate,in
thatlossesareminimal,butalreadywarmreachesareexposedtoadditionalwarminganddrying.
Vulnerabilityisalsomoderateinareaswherelengthsofcoldandtransitionalreacheswilldecline
substantially,butremainpresent.Areaswherecoldandtransitionalreachesremainpresentin
substantiallengthshavecomparativelylowvulnerability.
154 ColoradoNaturalHeritageProgram©2015
Figure 2.13.Modeledtransitionline.
ClimateChangeVulnerabilityAssessmentforColoradoBLM155
Cold+Transitionalreachescurrently>50km?
No Yes  
ModerateCold+Transitionalreachesinmid‐century>50km?
No Yes 
HighCold+Transitionalreachesinmid‐century>500km?
 No Yes
 ModerateCold+Transitionalreachesinmid‐century>10,000km?
  No Yes
  ModerateLow
Figure 2.14.Decision‐treeforexposurecriteriaappliedtoriversandstreams.
LakesandreservoirsarepoorlydistinguishedinmostGISdata,andtherearefewnaturallakesin
Coloradothathavenotbeenmodifiedtosomeextentforwaterstorage.Weconsideredanywater
bodywithsurfaceareagreaterthanorequalto3km2areservoir,andsmallerwaterbodieswere
classifiedaslakes.Bothlakesandreservoirsweredesignatedaseither“high”or“low”elevation,
accordingtotheirpositioninrelationtothemodeledtransitionaltemperatureline.GISmetrics
werecalculatedusingthesamesixdivisionsofthestateshowninFigure2.12,toaccountfornorth‐
southandeast‐westtemperaturedifferencesinherentinColorado.Exposurewascalculatedfor
lakesandreservoirsusingmethodssimilarforthoseusedinevaluatingterrestrialecosystems
(proportionofacreagewhereprojectedannualmeantemperatureformid‐centuryunderRCP8.5
wasgreaterthananyannualmeantemperaturescurrentlyexperiencedbythatecosystemwithin
Colorado,ANDprojectedfutureprecipitationchangeswerelessthan5%increaseovercurrent
levels,butwithoutadditionalmodifiers(Table2.11).
Table 2.11.Criteriaforscoringexposureoflakesandreservoirsfreshwaterecosystems.
PercentColoradoacreswithprojected
temp>max&pptdelta<5%36–100%16–35%0–15%
InitialExposure‐SensitivityScoreHighModerateLow
Resilience‐Adaptive Capacity Assessment – Freshwater Ecosystems
Thisscoresummarizesindirecteffectsandnon‐climatestressorsthatmayinteractwithclimate
changetoinfluencetheadaptivecapacityandresilienceofanecosystem.Factorsevaluatedare
adaptedfromthemethodologyusedbyManometCenterforConservationScienceand
MassachusettsDivisionofFishandWildlife(MCCSandMAFW2010),combinedunderfiveheadings
(Table2.12).Factorswerescoredonascaleof0(lowresilience)to1(highresilience).

156ColoradoNaturalHeritageProgram©2015
Table 2.12.Descriptionoffactorsusedtoassessresilience‐adaptivecapacityinfreshwaterecosystems.
Assessment factor Description
Restrictiontospecifichydro‐
geomorphicsetting
Fundamentalgeomorphiccharacteristicsthatdefinestreamandwetland
systems(elevation,slope,drainagearea)donotchangeappreciablyover
decades.However,headwaterstreamsareconstrainedbyupperlimitsto
watersheds,somelargerstreamsorriversareconstrainedattheirlower
limitsbythepresenceofwaterbodies,includinglargereservoirs,andlakes
orreservoirsarefixedinlocation.Inaddition,increasingtemperatureand
accompanyingchangesinhydrologyandwaterqualitycouldresultinthe
transitionofonestreamorrivertypetoanother.
Vulnerabilitytochangein
snowmelttimingand
magnitude,and/ordecreasing
baseflows
Thetimingandmagnitudeofsnowmeltrunoffprovideakeyhabitat
componentforsomeaquaticspecies.Earlierpeakflows,reducedflows,
changesinfloodfrequencyormagnitude,andtheoverallshapeofthe
hydrographmaychangeunderprojectedclimaticconditions.Effectscould
includeshiftsinspawningbehavior,aswellaslossordisplacementof
spawningbedsandotherimportanthabitatstructure.Lowerbaseflows,and
reducedgroundwaterdischargearepossibleunderprojectedincreased
temperatures.Thesechangescanreducehabitatarea,aswellasincreasing
habitatvulnerabilitytotemperatureandwaterqualitystress.Finally,if
overallwatersuppliesdecrease,anthropogeniceffortstodivertandstore
waterarelikelytoincreasethelevelofhydrologicmodificationinthese
ecosystems.
Vulnerabilitytoincreased
impactbybiologicalstressors
Thisfactorsummarizeswhetherexpectedfuturebiologicalstressors
(invasivespecies,pestsandpathogens)havehad,orarelikelytohave,an
increasedeffectduetointeractionswithchangingclimate.Climatechange
mayresultinmorefrequentormoresevereoutbreaksofthesestressors.
Ecosystemsthatarecurrentlyvulnerabletothesestressorsmaybecome
moresounderclimatechange.Aquaticpathogensofconcerninclude
whirlingdisease,giardia,andcryptosporidium.Increasedtemperaturesand
theresultinghydrologicchangesmaymakefreshwaterecosystemsmore
susceptibletoinvasionbynon‐nativespecies,includingquaggamussel,New
Zealandmudsnail,rustycrayfish,Eurasianmillefoil,andothers.Finally,native
species(e.g.,thealgaDidymospheniageminata)canproliferateasnuisance
speciesunderchangingclimaticconditions.
Vulnerabilitytoincreased
frequencyorintensityof
extremeevents
Thisfactorevaluatescharacteristicsofanecosystemthatmakeitrelatively
morevulnerabletoextremeevents(floods,drought,fire)thatareprojected
tobecomemorefrequentand/orintenseunderclimatechange.Flooding
anddroughtfrequencymayaltergeomorphicprocesses,sedimentation,
waterquality,andthestabilityofsmallpopulations.Anincreaseinlargefires
maychangesedimentloadsandwaterquality.
Otherindirecteffectsofnon‐
climatestressors
Thisfactorsummarizestheoverallconditionoftheecosystematthe
landscapelevelacrossColorado,andisderivedfromasummaryimpactscore
indexingthedegreeofhydrologicalmodificationandanthropogenic
disturbance(TNC2012).
ClimateChangeVulnerabilityAssessmentforColoradoBLM157
Restriction to specific hydro‐geomorphic setting
Scoresof0=lowresilience,0.5=intermediateoruncertainresilience,and1=highresiliencewere
assigned,basedonbestprofessionaljudgementfocusedontherelativevulnerabilityofeachtypein
comparisonwithothertypes.
Vulnerability to change in snowmelt timing and magnitude, and/or decreasing baseflows
Scoresof0=lowresilience,0.5=intermediateoruncertainresilience,and1=highresiliencewere
assigned,basedonbestprofessionaljudgementfocusedontherelativevulnerabilityofeachtypein
comparisonwithothertypes.
Vulnerability to increased impact by biological stressors
Foreachbiologicalstressor(invasivespeciesandpathogens‐pests)towhichanecosystemis
believedvulnerable,0.5wassubtractedfromadefaultscoreof1,toproducethefinalecosystem
score.
Vulnerability to increased frequency or intensity of extreme events
Foreachnon‐biologicalstressor(drought,flooding,andfire)towhichanecosystemisbelieved
vulnerable,0.33wassubtractedfromadefaultscoreof1,toproducethefinalecosystemscore.
Other indirect effects of non‐climate stressors
Resiliencetoclimatechangewasevaluatedusingthemeasuresofaquaticresourcecondition
databaseforColoradodevelopedbyTheNatureConservancy(2012).Thedatabaseincludesa
metricthatsummarizesconditionfactorsunderfiveprimaryheadingsasshowninTable2.13for
eachstreamreach.Thesummarymeasurerangesfrom1(verygoodcondition,littleornoimpact)
to4(poorcondition,heavilyimpacted).Wereportthelength‐weightedaverageofthesummary
metricbystreamorrivercategorywithinthesamethreeregions(Eastern,Mountain,Western)
describedabove.
Table 2.13.FactorsincludedinTNCfreshwatermeasuresofconditiondatabase.
Natural Flow Regime Riparian Condition Development Connectivity Water Quality
ConsumptiveUse
(AgriculturalUse,
MunicipalUse,
Transbasin
Diversions)
ReservoirStorage
RiparianLandUse
Non‐nativePlants
–Tamarisk–in
theRiparian
Vegetation
LandUse
RoadDensity
RoadCrossings
OilandGas
Mining
InstreamBarriers
toFish
Movement
Streamswitha
303dand/or
Monitoringand
Evaluation
Designation
Vulnerability Assessment Ranking
Overall Vulnerability Ranking
TheExposure‐SensitivityscoreandtheResilience‐AdaptiveCapacityscorearecombinedinthe
samewayasforterrestrialecosystems(Figure2.2)toproduceanoverallvulnerabilityrankfor
eachfreshwaterecosystem.
158ColoradoNaturalHeritageProgram©2015
FRESHWATER ECOSYSTEMS ‐ RESULTS
Table 2.14.Keyvulnerabilities,freshwaterecosystems.
Habitat Climate factor(s) Consequences Other considerations
Streams‐west WarmingwatertempsLossofcool‐waterreachesConnectivity;altered
hydrologyduetodiversions
Streams‐mtn.Timingandamountof
snowmelt/runoff
AlteredhydrographsConnectivity(including
transbasindiversion),
potentialforincreased
wildfiredisturbance
Streams‐eastWarmeranddrier
conditions
LossofperennialreachesConnectivity;altered
hydrologyduetodiversions
Rivers‐west WarmingwatertempsLossofcool‐waterreaches,
lowsummerflows
Connectivity(including
transbasindiversion),
potentialforincreased
wildfiredisturbance
Rivers‐mtn.Timingandamountof
runoff
AlteredhydrographsConnectivity(including
transbasindiversion)
Rivers‐eastTimingandamountof
runoff
AlteredhydrographsConnectivity;altered
hydrologyduetodamsand
diversions
Lakes,highWarmeranddrier
conditions
ReducedwaterqualityNitrogendeposition
Lakes,lowWarmeranddrier
conditions
LowwaterlevelsMunicipal&agricultural
supplypressure
Reservoirs,highTimingandamountof
snowmelt/runoff
EarlierhighwaterlevelsFloodcontrolreleases,
reducedlaterstorage
Reservoirs,lowWarmeranddrier
conditions
LowwaterlevelsMunicipal&agricultural
supplypressure

ClimateChangeVulnerabilityAssessmentforColoradoBLM159
STREAMS, RIVERS, LAKES, AND RESERVOIRS
FreshwaterecosystemsinColoradoincludebothcold‐andwarm‐waterstreamsandrivers,aswell
astransitionalcool‐waterstreamandriverreaches.Lakesandreservoirsarealsoincludedinour
analysis.
CNHPphotos
Climate Vulnerability Ranks:
Threeofthe10regionalecosystemsubtypesassessedhaveanoverallvulnerabilityrankofHigh,
andtwoarerankedVeryHigh(Table2.15).Theprimaryfactorcontributingtothehighexposure
rankingsforriversistheessentiallycompletelossofcurrentcoldandtransitionalreaches.Lakes
andreservoirsatallelevationsareprojectedtoexperiencetemperaturesoutsidethecurrentrange,
aswellaseffectivelydrierconditions.Mostecosystemsubtypeswereassessedashavingmoderate
resilience,withonlymountainstreamshavinghighresilienceandlowoverallvulnerabilitybymid‐
century.
160ColoradoNaturalHeritageProgram©2015
Table 2.15.Vulnerabilityranksummaryforallassessedfreshwaterecosystems.
Freshwater Ecosystem Target
Exposure ‐
Sensitivity final
ranking
Resilience ‐
Adaptive capacity
final ranking
Combined
ranks
Overall
vulnerability
rank
StreamsWestModerateModerateM/MModerate
StreamsMountainLowHighL/HLow
StreamsEastModerateModerateM/MModerate
  
RiversWestHighModerateH/MHigh
RiversMountainModerateModerateM/MModerate
RiversEastHighModerateH/MHigh
  
Lakes‐highHighHighH/MModerate
Lakes‐lowHighLowH/LVeryHigh
  
Reservoirs‐highModerateModerateM/MModerate
Reservoirs‐lowHighLowH/LVeryHigh
Vulnerability summary
Key vulnerabilities:
RiversandStreams
Warmingwatertemperaturesareexpectedtoleadtolossofcool‐waterreachesinbothriversand
streamsinwesternColorado,andtolowersummerflows.Warmertemperatureswillgenerallyresultin
earliersnowmeltandrunoffformountainstreamsandrivers.IneasternColorado,warmeranddrier
conditionsarelikelytoreducetheextentofperennialstreamreaches,andalterthehydrographsof
largeriversthatdependonsnowmelt.Nearlyallriverandstreamhabitatsarealreadyimpactedbydams
anddiversionsthathavedegradedtheconnectivityandhydrologyoftheecosystem.
LakesandReservoirs
Warmeranddrierconditionsforlowerelevationlakesandreservoirsarelikelytoresultingenerally
lowerwaterlevelsunderpressurefrommunicipalandagriculturalconsumers.Highelevationlakesmay
seereducedwaterqualityastemperatureswarm;someareasarealreadyaffectedbynitrogen
deposition.Changesintimingandamountofsnowmeltrunoffmaychangestoragepatternsinhigher
elevationreservoirs;earlyfloodcontrolreleasesmayleadtoreducedlate‐seasonwaterlevels.
Smallerloticecosystems(streams)havegenerallylowervulnerability,especiallyathigher
elevationswherecoldwaterreachesarelikelytoremainviable.Theprimaryfactorcontributingto
highorveryhighvulnerabilityranksforfreshwaterecosystemsistheprojectedchangeinthe
transitionzonebetweenwarmandcoldwaterareas.Mostfreshwaterecosystemswererankedas
moderatelyresilient,indicatingthattherearelikelytobemanagementopportunitiestomitigate
someeffectsofexposuretowarmerconditions.
ClimateChangeVulnerabilityAssessmentforColoradoBLM161
Distribution
FreshwaterecosystemsinColoradoarefoundthroughoutthestate,althoughperennialstreamsand
lakesaremorecommonathigherelevations.WiththeexceptionoftheGreenRiver,whichcrosses
thenorthwesterncornerofthestate,allofColorado’smajorriversoriginatewithinthestateand
flowawayfromthecontinentaldivide.Totheeastofthedivide,streamsandriversdraintoward
theGulfofMexico.Onthewesternslope,flowingwatersaretributarytotheColoradoRiver,
drainingtowardthePacificOcean.ConditionsinColoradowatershedsaffectmanydownstream
users,bothwithinthestate’sbordersandbeyond.WaterdistributioninColoradohasevolveda
complexsystemofdiversions,irrigationwells,andwaterstoragefacilitiesthathavealteredthe
originalhydrologicregimeofmanyareas.
Environment
Freshwaterecosystemsasevaluatedinthisassessmentareallpartofaninterconnectedhydrologic
networkthatincludesbothsurfaceandgroundwater.Forthepurposesofourassessment,we
dividethesurfacewatersofthisnetworkintoseveralbroadtypesbysize,flowpatterns,and
location.Flowingwatersofstreamorder5through7(thelargestinColorado)arediscussedherein
as“rivers”,whileflowingwatersoflowerorderaretermed“streams.”Underthisgrouping,rivers
includethelargerperennialstreamreaches,togetherwiththeirmajortributaries,thatdrain
watershedsontheorder10,000+squaremilesinextent.Streamsincludeallothersmallerreaches
bothperennialandintermittent,fromheadwaterstotheirjunctionwithrivers,ifany.
Lakesandreservoirsarealsopartofthehydrologicnetwork,buthavegenerallymuchslower
current,suchthattheygenerallyappearasstandingbodiesofwater,andmaybeisolatedfrom
perennialsurfaceflow.Becausemanylakeshavebeenmodifiedtosomeextenttoregulatewater
flow,wegroupedlargerimpoundments(greaterthanorequalto3km2inarea)togetheras
reservoirs,andsmallerwaterbodies(lessthan3km2inarea)aslakes,regardlessofmodification.
Finally,weassessedfreshwaterhabitatsaccordingtoelevationandregionallocationwithinthe
state.
Dynamics
BaronandPoff(2004)identifiedfivedynamicfactorsthatshapethestructureandfunctionof
freshwaterecosystems:theflowpatternofwaterthroughthesystem,inputsofsedimentand
organicmatter,nutrientandchemicalconditions,temperatureandlightlevels,andplantand
animalassemblages.
Flowpatternsdescribethewaywaterpassesintoandoutofstreams,rivers,lakesandassociated
wetlands.Importantcharacteristicsincludebaseflowlevels,theperiodicityandmagnitudeofboth
annualorfrequentfloodsandrareandextremefloodevents,seasonalityofflows,andannual
variability(BaronandPoff2004).Patternsofwaterflowandtheirinteractionwithlocallandforms
andsubstratesatavarietyofscalesaretheprimarydeterminantofphysicalhabitatforriver
organisms.Aquaticorganismsevolvedwithandareadaptedtothecharacteristicnaturalflow
regimeoftheirhabitat;changesinflowregimecancauseseriousdisruptiontothereproduction
andsurvivalofmanyaquaticspecies,leadingtoaneventuallossofbiodiversity(Bunnand
Arthington2002).Reducedconnectivityinaquatichabitats,bothin‐streamandbetweentheriver
162ColoradoNaturalHeritageProgram©2015
channelandassociatedfloodplainhabitats,reduceshabitatavailabilityanddiversity,with
consequentnegativeeffectsonthepopulationviabilityofaquaticspecies.Alteredflowregimes,and
transbasindiversionscanfacilitatetheinvasionandestablishmentofexoticspecies(Bunnand
Arthington2002).Finally,riverinesystemsacttointegrateandcollecttheeffectsofdisturbances
withinthecatchment,includingthoseduetoflowmodification(Naimanetal.2002).
Sedimentandorganicmatterinputstofreshwaterecosystemsmayincludebothnaturaland
anthropogenicsources.Thearrivalofnaturalorganicmatter(e.g.,plantmaterial)fromadjacent
uplandareasisaregularseasonaloccurrence,andsedimentmovementsoccurnaturallywith
seasonalandinterannualvariationinwaterflow.Manyplantandanimalspeciesofthesehabitats
arecloselyadaptedtospecificsedimentandorganicmatterconditions,andareeasilyeliminatedby
changesintheenvironment(BaronandPoff2004).Anthropogenicdisturbancessuchas
agriculture,logging,roadconstruction,dams,anddiversionshavehighlymodifiedthenatural
sedimentandorganicinputoffreshwaterecosystems.Unmodifiedstreamsdisplayamosaicof
habitatscreatedbyflowandsedimentationpatterns.Extensiveremovalofbeaverthroughout
Coloradointhefirsthalfofthe19thcenturyprobablyhadaconsiderableeffectonchannel
structure,diversity,andstability,aswellassedimentlevelsinmountainstreams(Wohl2006).
Placerminingwasanevenstrongeragentofhydrologicmodificationinmanyareas.Diversion
damstendtoshifthabitattowardslowerflowandincreasedfinesedimentation(Bakeretal.2011).
Thelegacyofthesehistoricanthropogenicdisturbancesisreducedhabitatsuitabilityfornative
species.
Naturalnutrientandchemicalconditionsinfreshwaterecosystemsarelargelydeterminedby
climate,bedrock,soil,vegetation,andtopographyinthevicinity,andareconsequentlyhighly
variablebylocale(BaronandPoff2004).Humanactivitiescanaddnutrients(eutrophication),ora
varietyofman‐madechemicals(herbicides,pesticides,pharmaceuticals,etc.)thatchangethe
speciescompositionandqualityofthesehabitats(Carpenter1998).
Watertemperatureiskeyindeterminingoxygenconcentrationandthelifeprocessesofaquatic
organisms.Patternsoftemperatureandsolarenergyabsorptiondifferbetweenmovingandstill
waters.Thereleaseofcoldwaterfromreservoirstorageinterruptsthenaturaltemperature
patternsimmediatelydownstream.
Changingclimateconditionscanaffectallthesefactors,butdirectlyactthroughtemperatureand
flow.
Characteristic species
Thecompletebioticcommunityofanaquaticecosystemincludesplantsandalgae,aswellas
invertebrateandvertebrateanimals.Environmentalconditionsanddynamicsinpartdeterminethe
plantandanimalassemblagesthatwillbeassociatedwithaparticularfreshwaterecosystem.In
turn,thebiotaareactiveparticipantsinecologicalprocesses.Acompletedescriptionofspecies
characteristicofColorado’sfreshwaterecosystemsisbeyondthescopeofthisassessment,but
commonandimportantmacroinvertebratesincludecrustaceansandspeciesofEphemeroptera,
Plecoptera,Trichoptera,andOdonata,amongothers.
ClimateChangeVulnerabilityAssessmentforColoradoBLM163
FishofColorado’sfreshwaterecosystemsincludebothnativeandintroducedspecies.Fishspecies
showninTable2.16arerepresentativeofsomeofthefreshwaterecosystemsevaluated.
Vulnerabilityresultsfromspecies‐specificClimateChangeVulnerabilityIndexanalysis(seeChapter
3)areshown,ifavailable.
Table 2.16.Representativefishspeciesforfreshwaterecosystems.
Cold Water Transitional
Warm
Water Lakes ‐ high
Representative fish
species CCVI rank
Rivers
Streams
Rivers
Streams
Rivers
Streams
ColoradoRiverCutthroatExtremelyvulnerableXXXX  X
GreenbackCutthroatXXXX  X
RioGrandeCutthroatExtremelyvulnerableXXXX  X
MottledsculpinXXXX 
SpeckleddaceXXXX 
BrowntroutXX 
BlueheadsuckerHighlyvulnerableXXXX
FlannelmouthsuckerHighlyvulnerableXXXX
RoundtailChubHighlyvulnerable XXXX
BonytailchubExtremelyvulnerable XX 
ColoradopikeminnowExtremelyvulnerable XX 
HumpbackchubExtremelyvulnerable XX 
RazorbacksuckerHighlyvulnerableXX 
164ColoradoNaturalHeritageProgram©2015
CCVA Scoring
Exposure‐Sensitivity (Potential Impact) Ranks
Ecosystem Method Score
StreamsWestDecisiontreeModerate
StreamsMountainDecisiontreeLow
StreamsEastDecisiontreeModerate
 
RiversWestDecisiontreeHigh
RiversMountainDecisiontreeModerate
RiversEastDecisiontreeHigh
 
Lakes–highelev.Avg.“outofrange”High
Lakes–lowelev.Avg.“outofrange”High
 
Reservoirs–highelev.Avg.“outofrange”Moderate
Reservoirs–lowelev.Avg.“outofrange”High
Underthescopeofouranalysis,thetotalstreamandriverlengthpresentinthestateisassumedto
remainconstantbetweenthepresentandmid‐century.Theeffectsofwarmingtemperatureare
measuredbycomparingtheproportionofstreamandriverreachesthatmovefromonecategoryto
thenext.Undertheconstraintsofthetechnique,areachcanremaininthesamecategory,ormove
toawarmercategory,butnevermovetoacoolercategory.
Asexpected,bothstreamsandriversinthemountainregionarecurrentlydominatedbycoldwater
reaches,andtherearelimitedcoldwaterreachespresentinboththeeasternandwesternregions
(Figure2.15,Table2.17).Cooltocoldwatertransitionreachesarecurrentlymostcommonin
westernriversandstreams.Botheasternandwesternriversandstreamscurrentlyhavea
significantproportionofwarmwaterreaches.
StatewidepatternsoftransitionareshowninFigure2.16.Anoverallretreatofcoldwater
conditionstohigherelevationsisevident.Majorriversonboththeeastandwestslopeare
projectedtoseewarmerwatertemperaturesfarupstream.Thiseffectisparticularlyevidentonthe
westernrivers.
Underprojectedwarmingwatertemperaturesatmid‐century,forallregionstheproportionof
warmwaterreachlengthincreases.Transitionalareasgenerallymoveupinelevation,andbecome
concentratedinthemountainregion.Withoutaccountingforwatertemperaturesmaintainedby
storagerelease,coldwaterreachesessentiallydisappearfromthelowerelevationsofbotheastern
andwesternColorado.
ClimateChangeVulnerabilityAssessmentforColoradoBLM165
Exposureto“outofrange”conditionsforlakesandreservoirswaslowestforhighelevation
reservoirs.Bothlowandhighelevationlakeswereinthemoderatelyvulnerablecategory,although
higherelevationlakeshadslightlylessexposure.Lowelevationreservoirshadhighestexposure
underprojectedmid‐centuryclimateconditions.
Figure 2.15.Categorytransitionsbetweencurrentandprojected(RCP8.5)conditionsforstreamsandrivers.

166ColoradoNaturalHeritageProgram©2015
Table 2.17.Reachlengthstatistics(km)forwatertemperaturecategoriesbothstatewideandbyregion.
Cold Water Transitional Warm Water
Statewide: Rivers Streams Rivers Streams Rivers Streams
Current 1,394 64,728 395 12,342 4,48063,386
%Total1% 44% 0% 8% 3%43%
RCP8.5560 36,882 117 14,227 5,59189,348
%Total0.4% 25% 0.1% 10% 4%61%
%changefromCurrent‐60% ‐43% ‐70% 15% 25%41%
By Region:   
West Slope    
Current58 3,044 129 4,564 1,40818,515
%Total0.2% 11% 0.5% 16% 5%67%
RCP8.5020 0362 1,59625,741
%Total0% 0.07% 0% 1% 6%93%
%changefromCurrent‐100% ‐99% ‐100% ‐92% 13%39%
  
Southern Rocky Mountains    
Current1,321 59,640 245 5,640 5693,547
%Total2% 84% 0% 8% 1%5%
RCP8.5560 36,862 117 13,663 1,45618,303
%Total1% 52% 0.2% 19% 2%26%
%changefromCurrent‐58% ‐38% ‐52% 142% 156%416%
  
Eastern Plains    
Current15 2,044 14 2,138 2,51041,324
%Total0.03% 4% 0.03% 4% 5%86%
RCP8.50 0 0 201 2,53945,304
%Total0% 0% 0% 0.4% 5%94%
%changefromCurrent‐100% ‐100% ‐100% ‐91% 1%10%

ClimateChangeVulnerabilityAssessmentforColoradoBLM167
Figure 2.16.Comparisonofcurrent(top)andprojected(bottom)streamtemperatureclassification.
168ColoradoNaturalHeritageProgram©2015
Resilience and Adaptive Capacity Ranks
Ecosystem Score Rank
StreamsWest0.54Moderate
StreamsMountain0.71High
StreamsEast0.61Moderate

RiversWest0.49Moderate
RiversMountain0.58Moderate
RiversEast0.66Moderate

Lakes‐high0.68High
Lakes‐low0.39Low

Reservoirs‐high0.59Moderate
Reservoirs‐low0.27Low
Restrictiontospecifichydro‐geomorphicsetting
Highelevationlakesarescoredasmostrestrictedbytheirlocation.Otherwaterbodiesarescored
asintermediateinlocationrestriction,asarehigherelevationstreamsandrivers.Lowerelevation
streamsandriversarepresumedtobeunrestricted.
Ecosystem Score
StreamsWest1
StreamsMountain0.5
StreamsEast1
RiversWest1
RiversMountain0.5
RiversEast1
Lakes–highelev.0
Lakes–lowelev.0.5
Reservoirs–highelev.0.5
Reservoirs–lowelev.0.5

ClimateChangeVulnerabilityAssessmentforColoradoBLM169
Vulnerabilitytochangeinsnowmelttimingandmagnitude,and/ordecreasingbaseflows
Streams,lakes,andreservoirsofhighelevationsarescoredasleastvulnerabletochangesin
snowmelttimingandmagnitude,andwithlessvulnerabilitytodecreasingbaseflows,underthe
assumptionthathigherelevationsarelesslikelytoseeeffectivelydrierconditionsbymid‐century.
Streams,rivers,andlakesoflowerelevationsarescoredashavingintermediatevulnerabilityfor
thesefactors,basedontheassumptionthattheeffectsofincreasingtemperaturesandeffectively
drierconditionswilltendtoaccumulateinthesedownstreamreaches.Lowelevationreservoirsare
assumedtobemostvulnerable.
Ecosystem Score
StreamsWest0.5
StreamsMountain1
StreamsEast0.5
RiversWest0.5
RiversMountain0.5
RiversEast1
Lakes–highelev.1
Lakes–lowelev.0.5
Reservoirs–highelev.1
Reservoirs–lowelev.0
Vulnerabilitytoincreasedimpactbybiologicalstressors
Ingeneral,freshwaterhabitatsofthehighestelevationsarescoredasnotvulnerabletoincreased
impactbypathogensorinvasives,duetocomparativelycoolertemperaturesintheseareas,andthe
currentlowlevelsofsuchstressors.Lowelevationecosystemsarescoredasmorevulnerableto
invasivespeciesandpathogens,duetothewarmertemperatures,andthefactthatsomeinvasives
andpathogensarealreadypresentinthesehabitats.
Ecosystem Score Factors
StreamsWest0.5Pathogens
StreamsMountain1 ‐‐‐
StreamsEast0.5Invasives
RiversWest0Pathogens&Invasives
RiversMountain1 ‐‐‐
RiversEast0.5Invasives
Lakes–highelev.1 ‐‐‐
Lakes–lowelev.0Pathogens&Invasives
170ColoradoNaturalHeritageProgram©2015
Ecosystem Score Factors
Reservoirs–highelev.0.5Invasives
Reservoirs–lowelev.0Pathogens&Invasives
Vulnerabilitytoincreasedfrequencyorintensityofextremeevents
Increasingfrequencyandseverityofdroughtistheprimaryfactorthatislikelytoincrease
vulnerabilityoffreshwaterecosystems.Streamsinwesternandmountainareasarescoredasbeing
vulnerabletoincreasedsedimentationfollowingapotentialincreaseinfirefrequency.Mountain
riversarescoredasvulnerabletoapotentialincreaseinextremeprecipitationevents.High
elevationlakesarenotthoughttobevulnerableinthiscategory.
Ecosystem Score Factors
StreamsWest0.33Drought,fire
StreamsMountain0.67Fire
StreamsEast0.67Drought
RiversWest0.67Drought
RiversMountain0.67Flooding
RiversEast0.67Drought
Lakes–highelev.1 ‐‐‐
Lakes–lowelev.0.67Drought
Reservoirs–highelev.0.67Drought
Reservoirs–lowelev.0.67Drought
Otherindirecteffectsofnon‐climatestressors
Thelength‐weightedmeanscorebyregionforthesummaryconditionfactor(TNC2012)was
convertedtoaproportionofpotentialbestscore(4)usingtheformula:1–((regionmean‐1)/3).A
lowermeanbeforescoreconversionindicatesbettercondition,andhigherresilience.Ingeneral,
higherelevationareasareinbettercondition.
Ecosystem Mean Score
StreamsWest2.570.48
StreamsMountain2.450.52
StreamsEast2.570.48
RiversWest2.940.35
RiversMountain3.080.31
RiversEast3.530.16
Lakes–highelev.2.340.55
Lakes–lowelev.2.800.40
ClimateChangeVulnerabilityAssessmentforColoradoBLM171
Ecosystem Mean Score
Reservoirs–highelev.2.940.35
Reservoirs–lowelev.3.250.25
Conclusions
Allfreshwaterecosystemsareexpectedtobeaffectedtosomeextentbyclimatechange.Aswater
temperatureschange,somewarm‐waterhabitattypesmayexpandattheexpenseofcool‐orcold‐
watertypes.Nearlyallevaluatedfreshwatertypeswererankedwithmoderatetoveryhigh
vulnerabilityinouranalysis,withreasonablecertaintythatthesehabitatswillbeimpactedby
climatechange.Althoughwedidnotincorporatefreshwaterfishspecies‐specificscoringintoour
vulnerabilityanalysis,thoseresults(Chapter3)tendtosupportthegenerallyhighervulnerability
levelsforfreshwaterecosystems.Uncertaintyintheevaluationisduetouncertaintyinclimate
projections,thescopeofcurrentknowledge,andongoingmanagementactions.
Thereisevidencefrommonitoringrecordsthatwarmerairtemperatureshavealreadyaffected
watertemperaturesandhydrographsinmountainstreams(Isaaketal.2012).Bymid‐century,
underbothmoderateandhighradiativeforcingscenarios(RCP4.5andRCP8.5),wecanexpectto
seeevenwarmertemperaturesstatewide,especiallyontheeasternplains.Warmerair
temperaturesareexpectedtoleadtowarmerwatertemperatures,earliersnowmelt,lossof
permanenticefields,andpossiblydrierconditions.Evenifprecipitationlevelsathigherelevations
areessentiallyunchanged,warmerconditionswillleadtomoreprecipitationfallingasraininstead
ofsnow,adecreasedsnowpack,earlierrunoff,andearlierdryconditionsinlatesummer(Lucaset
al.2014).Allofthesefactorsarelikelytointeractwithstressesarisingfromalteredhydrology
(dams,diversions,etc.),andsocio‐economicdemandsforcontinuedwateravailabilityatpreviously
establishedlevels.
ThehighlymanagednatureofwaterresourcesinColoradotosomeextentconfoundsour
preliminaryevaluationofvulnerabilitytoclimatechangefortheseecosystems.Waterstorageand
releasepatternsdonotalwaysmimicconditionsthatwouldbefoundonanunmanipulatedreach,
andthismaybenefitsomespecieswhileharmingothers.Furthermore,theimpactsofwarming
temperaturesandpotentiallychangingprecipitationpatternsonfreshwaterecosystemscanbe
enhancedbyfragmentationormitigatedbyincreasedconnectivityintheseinterconnected
networksofhabitats.Formostspecies,intactconnectivitywithinthehydrologicnetworkwillbe
crucialforadaptationtochangingconditions;however,speciesassemblagesarelikelytochangeas
lessmobilecommunitymembersareeliminated.Enhancingconnectivitywithconcomitant
reductioninanthropogenicstressesislikelytobethemostproductiveapproachforconserving
freshwaterecosystemsunderfutureclimaticconditions(Khamisetal.2014).
Strategiesformeetingthechallengesoffutureconditionsareperhapsmostcomplexandyetmost
urgentforfreshwaterecosystems.Althoughdaunting,earlieractionislikelytoallowincreased
opportunityforfutureadaptivemanagementthandelayorinaction.
172ColoradoNaturalHeritageProgram©2015
Literature Cited
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hydraulicconditionsofRockyMountainStreams.RiverResearchandApplications27:388‐401.
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ResourcesUpdate127:52‐58.
Bunn,S.E.andA.H.Arthington.2002.Basicprinciplesandecologicalconsequencesofalteredflowregimesforaquatic
biodiversity.EnvironmentalManagement30:492‐507.
Carpenter,S.R.,N.F.Caraco,D.L.Correll,R.W.Howarth,A.N.Sharpley,andV.H.Smith.1998.Nonpointpollutionofsurface
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pastaspreludetothefutureforunderstanding21st‐centuryclimateeffectsonRockyMountaintrout.Fisheries37:542‐
556.
Khamis,K.,D.M.Hannah,M.HillClarvis,L.E.Brown,E.Castella,andA.M.Milner.Alpineaquaticecosystemconservation
policyinachangingclimate.EnvironmentalScience&Policy43:39‐55.
Lucas,J.,J.Barsugli,N.Doesken,I.Rangwala,andK.Wolter.2014.ClimateChangeinColorado:asynthesistosupport
waterresourcesmanagementandadaptation.Secondedition.ReportfortheColoradoWaterConservationBoard.
WesternWaterAssessment,CooperativeInstituteforResearchinEnvironmentalSciences(CIRES),UniversityofColorado
Boulder.
Naiman,R.J.,S.E.Bunn,C.Nilsson,G.E.Petts,G.Pinay,L.C.Thompson.2002.Legitimizingfluvialecosystemsasusersof
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TheNatureConservancy[TNC].2012.FreshwatermeasuresofconditionforColorado.Geodatabase.
Wohl,E.2006.Humanimpactstomountainstreams.Geomorphology79:217‐248.

ClimateChangeVulnerabilityAssessmentforColoradoBLM173
3 ANIMALS
Authors:
JeremySiemers
BernadetteKuhn
BradLambert
RobertSchorr
JohnSovell
Recommendedchaptercitation:
Siemers,J.,B.Kuhn,B.Lambert,R.Schorr,andJ.Sovell2015.Animals.Chapter3InColoradoNaturalHeritageProgram2015.
ClimateChangeVulnerabilityAssessmentforColoradoBureauofLandManagement.K.Decker,L.Grunau,J.Handwerk,andJ.
Siemers,editors.ColoradoNaturalHeritageProgram,ColoradoStateUniversity,FortCollins,Colorado.
174ColoradoNaturalHeritageProgram©2015
TableofContents–3Animals
Methods....................................................................................................................................................176
Results.......................................................................................................................................................180
AnimalSpeciesCCVASummaries.............................................................................................................182
Borealtoad................................................................................................................................................183
CanyonTreefrog........................................................................................................................................187
GreatBasinSpadefoot..............................................................................................................................191
NorthernLeopardFrog.............................................................................................................................195
AmericanPeregrineFalcon....................................................................................................................... 199
BlackSwift.................................................................................................................................................203
Brewer’sSparrow......................................................................................................................................206
BurrowingOwl..........................................................................................................................................210
GoldenEagle.............................................................................................................................................214
Greatersage‐grouse.................................................................................................................................218
Gunnisonsage‐grouse...............................................................................................................................222
Long‐BilledCurlew....................................................................................................................................226
MountainPlover.......................................................................................................................................230
NorthernGoshawk....................................................................................................................................235
WesternSnowyPlover..............................................................................................................................239
WesternYellow‐billedCuckoo.................................................................................................................. 243
White‐facedIbis............................................................................................................................... .........247
BlueheadSucker.......................................................................................................................................251
BonytailChub............................................................................................................................................256
Coloradopikeminnow...............................................................................................................................260
ColoradoRiverCutthroatTrout................................................................................................................265
FlannelmouthSucker................................................................................................................................270
HumpbackChub........................................................................................................................................274
RazorbackSucker......................................................................................................................................278
RioGrandeCutthroatTrout......................................................................................................................282
RoundtailChub.........................................................................................................................................286
GreatBasinSilverspot...............................................................................................................................290
Americanbeaver.......................................................................................................................................294
DesertBighornSheep...............................................................................................................................
297
ClimateChangeVulnerabilityAssessmentforColoradoBLM175
FringedMyotis..........................................................................................................................................301
GunnisonPrairieDog................................................................................................................................304
Townsend’sbig‐earedbat.........................................................................................................................308
White‐tailedprairiedog............................................................................................................................311
Desertspinylizard.....................................................................................................................................314
Longnoseleopardlizard............................................................................................................................318
Midgetfadedrattlesnake.........................................................................................................................321
ListofFiguresandTables
Figure 3.1.Summaryofclimatechangevulnerabilityscoresforanimalspecies.EV=Extremely
Vulnerable;HV=HighlyVulnerable;MV=ModeratelyVulnerable;PS=PresumedStable;IL=Increase
Likely.........................................................................................................................................................181
Table 3.1.Climatechangevulnerabilityscoresforanimalspecies.EV=ExtremelyVulnerable;HV=
HighlyVulnerable;MV=ModeratelyVulnerable;PS=PresumedStable;IL=IncreaseLikely................180

176ColoradoNaturalHeritageProgram©2015
METHODS
NatureServe Climate Change Vulnerability Index
Overview
Thisoverviewhasbeensynthesizedandreprinted,withpermission,fromYoungetal.(2011).The
ClimateChangeVulnerabilityIndex(CCVI),developedbyNatureServe,isaMicrosoftExcel‐based
toolthatfacilitatesrapidassessmentofthevulnerabilityofplantandanimalspeciestoclimate
changewithinadefinedgeographicarea.Inaccordancewithwell‐establishedpractices(Schneider
etal.2007,Williamsetal.2008),theCCVIdividesvulnerabilityintotwocomponents:
exposuretoclimatechangewithintheassessmentarea(e.g.,ahighlysensitivespecieswill
notsufferiftheclimatewhereitoccursremainsstable).
sensitivityofthespeciestoclimatechange(e.g.,anadaptablespecieswillnotdeclineeven
inthefaceofsignificantchangesintemperatureand/orprecipitation).
Exposuretoclimatechangeismeasuredbyexaminingthemagnitudeofpredictedtemperatureand
moisturechangeacrossthespecies’distributionwithinthestudyarea.CCVIguidelinessuggest
usingthedownscaleddatafromClimateWizard(http://climatewizard.org)forpredictedchangein
temperature.ProjectionsforchangesinprecipitationareavailableinClimateWizard,but
precipitationestimatesaloneareoftenanunreliableindicatorofmoistureavailabilitybecause
increasingtemperaturespromotehigherratesofevaporationandevapotranspiration.Moisture
availability,ratherthanprecipitationperse,isacriticalresourceforplantsandanimalsand
thereforeformstheotherpartoftheexposuremeasurewithintheCCVI,togetherwith
temperature.Topredictchangesinmoistureavailability,NatureServeandpartnersdevelopedthe
HamonAET:PETmoisturemetricaspartoftheCCVI.Themetricrepresentstheratioofactual
evapotranspiration(i.e.,theamountofwaterlostfromasurfacethroughevaporationand
transpirationbyplants)topotentialevapotranspiration(i.e.,thetotalamountofwaterthatcould
beevaporatedundercurrentenvironmentalconditions,ifunlimitedwaterwasavailable).Negative
valuesrepresentdryingconditions.
Sensitivityisassessedusing20factorsdividedintotwocategories:1)indirectexposuretoclimate
change;and2)speciesspecificfactors(includingdispersalability,temperatureandprecipitation
sensitivity,physicalhabitatspecificity,interspecificinteractions,andgeneticfactors).Foreach
factor,speciesarescoredonaslidingscalefromgreatlyincreasing,tohavingnoeffecton,to
decreasingvulnerability.TheCCVIaccommodatesmorethanoneanswerperfactorinorderto
addresspoordataorahighlevelofuncertaintyforthatfactor.Thescoringsystemintegratesall
exposureandsensitivitymeasuresintoanoverallvulnerabilityscorethatindicatesrelative
vulnerabilitycomparedtootherspeciesandtherelativeimportanceofthefactorscontributingto
vulnerability.
ClimateChangeVulnerabilityAssessmentforColoradoBLM177
TheIndextreatsexposuretoclimatechangeasamodifierofsensitivity.Iftheclimateinagiven
assessmentareawillnotchangemuch,noneofthesensitivityfactorswillweighheavily,anda
speciesislikelytoscoreattheNotVulnerableendoftherange.Alargechangeintemperatureor
moistureavailabilitywillamplifytheeffectofanyrelatedsensitivity,andwillcontributetoascore
reflectinghighervulnerabilitytoclimatechange.Inmostcases,changesintemperatureand
moistureavailabilitywillcombinetomodifysensitivityfactors.However,forfactorssuchas
sensitivitytotemperaturechange(factor2a)orprecipitation/moistureregime(2b),onlythe
specifiedclimatedriverwillhaveamodifyingeffect.
Thesixpossiblescoresare:
ExtremelyVulnerable:Abundanceand/orrangeextentwithingeographicalareaassessed
extremelylikelytosubstantiallydecreaseordisappearby2050.
HighlyVulnerable:Abundanceand/orrangeextentwithingeographicalareaassessedlikelyto
decreasesignificantlyby2050.
ModeratelyVulnerable:Abundanceand/orrangeextentwithingeographicalareaassessedlikely
todecreaseby2050.
NotVulnerable/PresumedStable:Availableevidencedoesnotsuggestthatabundanceand/or
rangeextentwithinthegeographicalareaassessedwillchange(increase/decrease)substantially
by2050.Actualrangeboundariesmaychange.
NotVulnerable/IncreaseLikely:Availableevidencesuggeststhatabundanceand/orrangeextent
withingeographicalareaassessedislikelytoincreaseby2050.
InsufficientEvidence:Availableinformationaboutaspecies'vulnerabilityisinadequateto
calculateanIndexscore.
Scoring Factors in the CCVI
ThefactorsusedtogeneratetheCCVIscorearelistedinthefollowingsection.Detaileddefinitions
ofscoringcategoriesarelistedinAppendixB.
A.ExposuretoLocalClimateChange
1. Temperature
2. Moisture
B.IndirectExposuretoClimateChange
1. Exposuretosealevelrise.(NotapplicabletoColorado)
2. Distributionrelativetonaturalandanthropogenicbarriers.
178ColoradoNaturalHeritageProgram©2015
3. Predictedimpactoflandusechangesresultingfromhumanresponsestoclimate
change.
C.Sensitivity
1. Dispersalandmovements.
2. Predictedsensitivitytotemperatureandmoisturechanges.
a.Predictedsensitivitytochangesintemperature.
b.Predictedsensitivitytochangesinprecipitation,hydrology,ormoisture
regime.
c.Dependenceonaspecificdisturbanceregimelikelytobeimpactedby
climatechange.
d.Dependenceonice,ice‐edge,orsnow‐coverhabitats.
3. Restrictiontouncommongeologicalfeaturesorderivatives.
4. Relianceoninterspecificinteractions.
a.Dependenceonotherspeciestogeneratehabitat.
b.Dietaryversatility(animalsonly).
c.Pollinatorversatility(plantsonly).
d.Dependenceonotherspeciesforpropaguledispersal.
e.FormspartofaninterspecificinteractionnotcoveredbyC4a‐d.
5. Geneticfactors.
a.Measuredgeneticvariation.
b.Occurrenceofbottlenecksinrecentevolutionaryhistory.
6. Phenologicalresponsetochangingseasonaltemperatureandprecipitation
dynamics.
D.DocumentedorModeledResponsetoClimateChange
1. Documentedresponsetorecentclimatechange.
2. Modeledfuturechangeinrangeorpopulationsize.
3. Overlapofmodeledfuturerangewithcurrentrange.
4. Occurrenceofprotectedareasinmodeledfuturedistribution.
Factorsnotconsidered—TheIndexdevelopmentteamdidnotincludefactorsthatarealready
consideredinconservationstatusassessments.Thesefactorsincludepopulationsize,rangesize,
anddemographicfactors.ThegoalisfortheNatureServeClimateChangeVulnerabilityIndexto
complementNatureServeConservationStatusRanksandnottopartiallyduplicatefactors.Ideally,
Indexvaluesandstatusranksshouldbeusedinconcerttodetermineconservationpriorities.
Application of Climate Data
Scoringfactorsrelatedtohistoricandpredictedfutureclimate(temperature,precipitation,and
moistureavailability,FactorsA1,A2,C2ai,andC2biintheCCVI)werecalculatedinGISusingthe
ClimateChangeVulnerabilityAssessmentforColoradoBLM179
methodsdescribedbelow.Refertothespeciesprofilesinthefollowingsectionofthisreportfor
detailsonscoringrationaleandreferencesforallotherfactors.
Exposuretopredictedtemperatureincreasewascalculatedusingspeciesdistributiondataandan
ensembleaverageof16CMIP3climatepredictionmodels(seeAppendixA)averagedoverthe
summerseason(June–August)usingthehigh(A2)CO2emissionsscenario.Thehighemissions
scenariowasusedbecauseitismostsimilartocurrentemissions.DatawereobtainedfromClimate
Wizard,andtheanalysisperiodwastotheyear2050(whichisactuallyanaverageofprojections
foryears2040–2069).Thesummerseason–growingseasonforplants,breedingseasonfor
animals–wasusedbecauseitwasconsideredthemostcriticaltimeperiodformostspecies.
Exposuretoprojecteddrying(integrationofprojectedtemperatureandprecipitationchange,i.e.,
theHamonAET:PETmoisturemetric)wascalculatedusingthedatasetcreatedbyNatureServeas
partoftheCCVI.NotethatNatureServebasedtheirmoisturemetriccalculationsonthesame
ClimateWizarddatasetasabove,exceptthattheyusedtheA1Bcarbondioxideemissionsscenario.
BecausethemodelingmethodsusedbyNatureServewerenotavailable,wewereunableto
recalculateusingtheA2scenario.Thus,weusedthedataasprovided,whichweconsidereda
reasonablealternativesincetheA1BandA2scenariospredictsimilarchangesthroughthemid‐21st
Century,theperiodusedinthisanalysis.Wecalculatedthepercentofeachspecies’range/
distributionthatfallswithineachratingcategory.Allcalculationsusedthe“summer”(June–
August)datasubset.
Thehistoricalthermalnichefactormeasureslarge‐scaletemperaturevariationthataspecieshas
experiencedinrecenthistoricaltimes(i.e.,thepast50years),asapproximatedbymeanseasonal
temperaturevariation(differencebetweenhighestmeanmonthlymaximumtemperatureand
lowestmeanmonthlyminimumtemperature).Itisaproxyforspecies'temperaturetoleranceata
broadscale.ThisfactorwascalculatedinGISbyassessingtherelationshipbetweenspecies’
distributionsandhistoricaltemperaturevariationdatadownloadedfromNatureServe.Historical
temperaturevariationwasmeasuredasthemeanJulyhighminusthemeanJanuarylow,using
PRISMdatafrom1951‐2006,expressedasasingleaveragedvaluefortheentirespeciesrange.
Thehistoricalhydrologicalnichefactormeasureslarge‐scaleprecipitationvariationthataspecies
hasexperiencedinrecenthistoricaltimes(i.e.,thepast50years),asapproximatedbymeanannual
precipitationvariationacrossoccupiedcellswithintheassessmentarea.Ratingsforthisfactor
werecalculatedinGISbyoverlayingthespecies’distributionsonmeanannualprecipitationdata
(PRISM4kmannualaverageprecipitation,ininches,1951‐2006)downloadedfromClimateWizard,
andsubtractingthelowestpixelvaluefromthehighestvalue.
Representing Species’ Distributions
Avarietyofsourceswereusedforanimalspecies,includingelementoccurrencerecordsand/or
observationdatafromCNHP’sdatabases,onlinedistributiondatafromCPW,existingspecies
distributionmodels,rangemapsfrompublishedliterature,andcriticalhabitatmaps.
180ColoradoNaturalHeritageProgram©2015
Thelistofanimalspeciesincludedinthisclimatechangevulnerabilityassessmentwasdeveloped
throughconsultationwithBLMstaff,usingtheBLMSensitiveSpecieslistasastartingpoint.This
listincludesallfederallylistedspecies.TheentireBLMsensitivelistwasbeyondthescopeofthe
project,sospecieswereprioritizedaccordingtothelevelofpriorworkavailableandthe
managementimportanceofthespecies.Afewwide‐rangingspeciesofparticularmanagement
interestthatarenotontheBLMsensitivelistwereincluded.
RESULTS
CCVIresultsaresummarizedinTable3.1,andpresentedinfullinAppendixC.Animal species results
are sorted alphabetically by common name within taxonomic group.Therationaleforscoringand
literaturecitationsareincludedinthefollowingspeciesprofiles.
Table 3.9.Climatechangevulnerabilityscoresforanimalspecies.EV=ExtremelyVulnerable;HV=Highly
Vulnerable;MV=ModeratelyVulnerable;PS=PresumedStable;IL=IncreaseLikely.
Taxonomic Group English Name Species Score
AmphibianBorealToadAnaxyrusboreasboreasHV
AmphibianCanyonTreefrogHylaarenicolorMV
AmphibianGreatBasinSpadefootSpeaintermontanaPS
AmphibianNorthernLeopardFrogLithobatespipiensMV
BirdAmericanPeregrineFalconFalcoperegrinusanatumPS
BirdBlackSwiftCypseloidesnigerPS
BirdBrewer'sSparrowSpizellabreweriPS
BirdBurrowingOwlAthenecuniculariahypugaeaMV
BirdGoldenEagleAquilachrysaetosMV
BirdGreatersage‐grouseCentrocercusurophasianusHV
BirdGunnisonSage‐grouseCentrocercusminimusHV
BirdLong‐billedCurlewNumeniusamericanusHV
BirdMountainPloverCharadriusmontanusPS
BirdNorhernGoshawkAccipitergentilisMV
BirdWesternSnowyPloverCharadriusalexandrinusnivosusHV
BirdWesternYellow‐billedCuckooCoccyzusamericanusoccidentalisMV
BirdWhite‐facedIbisPlegadischihiMV
FishBlueheadSuckerCatostomusdiscolobusHV
FishBonytailChubGilaelegansEV
FishColoradoPikeminnowPtychocheilusluciusEV
FishColoradoRiverCutthroatTroutOncorhynchusclarkiipleuriticusEV
FishFlannelmouthSuckerCatostomuslatipinnisHV
FishHumpbackChubGilacyphaEV
FishRazorbackSuckerXyrauchentexanusHV
ClimateChangeVulnerabilityAssessmentforColoradoBLM181
Taxonomic Group English Name Species Score
FishRioGrandeCutthroatTroutOnchorhynchusclarkiivirginalisEV
FishRoundtailChubGilarobustaHV
Invert‐InsectGreatBasinSilverspotSpeyerianokomisnokomisHV
MammalAmericanBeaverCastorcanadensisMV
MammalDesertBighornSheepOviscanadensisnelsoniMV
MammalFringedMyotisMyotisthysanodesPS
MammalGunnison'sPrairieDogCynomysgunnisoniPS
MammalTownsend'sBig‐earedBatCorynorhinustownsendiiPS
MammalWhite‐tailedPrairieDogCynomysleucurusPS
ReptileDesertSpinyLizardSceloporusmagisterPS
ReptileLongnoseLeopardLizardGambeliawislizeniiPS
ReptileMidgetFadedRattlesnakeCrotalusoreganusconcolorHV
Animalspeciesincludedfouramphibians,thirteenbirds,ninefish,oneinsect,sixmammals,and
threereptiles.Fivespecieswererankedasextremelyvulnerabletoclimatechange.Fish,in
particular,wererankedonthehightoextremelyvulnerableendoftherange(Figure3.1);other
taxonomicgroupsweregenerallymoreevenlydistributedbetweenpresumedstabletohighly
vulnerable.Noevaluatedspecieswereassessedaslikelytoincreaseunderfutureconditions.
Figure 3.1.Summaryofclimatechangevulnerabilityscoresforanimalspecies.EV=ExtremelyVulnerable;HV=
HighlyVulnerable;MV=ModeratelyVulnerable;PS=PresumedStable;IL=IncreaseLikely.

182ColoradoNaturalHeritageProgram©2015
ANIMAL SPECIES CCVI SUMMARIES
ClimateChangeVulnerabilityAssessmentforColoradoBLM183
Boreal toad
Anaxyrusboreasboreas
G4T1/S1
Family:Bufonidae
Climate Vulnerability Rank: Highly Vulnerable
ThisColoradostate‐widerankisbasedon:themajorityofborealtoadpopulationsinColorado
beingborderedbyhighmountainsthatactasnaturalbarriers,whichcouldlimittheabilityofthis
speciestoshiftitsrangeinresponsetoclimatechange;thephysiologicalnicheofthisspeciesbeing
coolerhighelevationareaswheresnowfallandsummerevaporationcouldaffectseasonalwetland
breedinghabitat;thedependenceofthisspeciesonspecifichydrologyforbreedingandthe
potentialdisruptionofthetimingofbreedingandlarvaldevelopmentbyclimatechange.Additional
importantrankingfactorsincludetheimportanceofsnowpacklevelsforbreedingpondwater
levelsandasaninsulatorforhibernation.Borealtoadsarealsooftendependentonbeaversto
createandmaintainbreedinghabitat.
Distribution:BorealtoadswerefoundhistoricallythroughoutthemountainousareasofColorado,
buthavenotbeenreportedfromtheSangreDeCristoMountainRange,WetMountains,orthePikes
Peakregion(Hammerson1999).BorealToadsarealsoabsentfromtheLaPlataMountainsand
UncompahgrePlateauinSouthwestColorado(CNHP2014).Habitat:Borealtoadsarerestrictedto
montanehabitatsatelevationsof8,000–12,200feet(2,400–3,400meters).Commonhabitats
includebeaverponds,wetmeadows,glacialkettlepondsandlakesinsubalpineforests
(Hammerson1999).Breedingoccursalongthemarginsofshallowpondsinstillwater.
Occasionally,floodedtireruts,man‐madepondsandstreambackflowsareusedaswellfor
breeding(Loeffler2001).
CCVI Scoring
Temperature:CalculatedusingClimateWizard:ensembleaverage,highemissionscenario(A2),
mid‐centurytimeframe,averageannualchange.InColoradobymid‐centurythisspeciesisexpected
184ColoradoNaturalHeritageProgram©2015
tobeexposedtomeanannualtemperatureincreasesof5.0oFto5.5oFover100percentofitsrange
(NatureServe2012).
Moisture:CalculatedinGISusingNatureServeHamonAET:PETmoisturemetricdata(thisindex
integratesprojectedtemperatureandprecipitationchangestoindicatehowmuchdryingwilltake
place).Rangewidethisspeciesispredictedtobeexposedtonetdryingofgreaterthan11.9percent
on17percentofitsrange,9.7to11.9percentdryingon49percentofitsrangeand7.4to9.6
percentdryingon32percentofitsrange(NatureServe2012).
B1)Exposuretosealevelrise.Neutral.
B2a)Distributionrelativetonaturalbarriers.Increase.Mountainrangeswithhigh,>12,500ft.
passesshouldbeconsideredasnaturalbarriersforborealtoadmovement(NatureServe2014).The
majorityofborealtoadpopulationsinColoradoaremostlyborderedbyhighmountains.
B2b)Distributionrelativetoanthropogenicbarriers.Neutral.Intensiveresidentialor
commercialdevelopmentandhightrafficvolumehighwayscouldbeconsideredasanthropogenic
barriers(NatureServe2014).ThemajorityofborealtoadpopulationsoccuronUSFSmanagedland
wheredevelopmentisverylow.
B3)Impactoflandusechangesresultingfromhumanresponsestoclimatechange.
Somewhatincreasetoneutral.Landalterationssuchas,timberharvest,grazing,recreationand
waterdevelopmentwouldlikelynotbebeneficialforborealtoadhabitat,buthavenotbeenshown
asprimarycausativeagentsfordeclinesinthesouthernRockyMountains(Loeffler2001).Landuse
changesassociatedwithclimatechangemaybeconsideredathreatbutthescopeandtypeof
changeintherangeoftheborealtoadishardtopredict.
C1)Dispersalandmovements.Somewhatdecreasetoneutral.Borealtoadsaredependentupon
breeding,foragingandhibernatinghabitat,whichencompassesbothwetlandanduplandhabitat
(Adamsetal.2005).Theevidenceshowsseasonalvariabilityintoadmovementsandindividual
movementsandindividualtoadsmaymove4kmormorebetweenbreedingandnonbreeding
habitat(Hammerson1999;Jones2000)anduptoapproximately7.6kmforanadultmale(Lambert
andSchneider2013).
C2ai)Predictedsensitivitytotemperature:historicthermalniche.Neutral.Therangeoccupied
bytheborealtoadintheassessedareahasexperiencedaverage(57.1‐77°F/31.8‐43°C)mean
seasonaltemperaturevariationinthelast50years.
C2aii)Predictedsensitivitytotemperature:physiologicalthermalniche.:Somewhatincrease.
TherangeofthisspeciesinColoradoisrestrictedtocoolerhighelevationareas.Reducedsnowfall
andincreasedsummerevaporationcouldhavedramaticeffectsonthedurationoroccurrenceof
seasonalwetlands(Corn2005).Longeractiveseasonswerefoundtoincreaserecruitmentattwo
breedingsitesinChaffeeCounty,Colorado(Lambertetal.InPrep),e.g.,increasedtemperatureswill
allowforearlierdevelopmentofyoungwithlargermetamorphsenteringhibernationthus
increasingoverwintersurvival.
ClimateChangeVulnerabilityAssessmentforColoradoBLM185
C2bi) Predictedsensitivitytochangesinprecipitation,hydrology,ormoistureregime:
historicalhydrologicalniche.Somewhatdecrease.Thisspecieshasundergonegreaterthan
average(>40inches/1,016mm)precipitationvariationoverthelast50years.
C2bii)Predictedsensitivitytochangesinprecipitation,hydrology,ormoistureregime:
physiologicalhydrologicalniche.Increase.Theborealtoadishighlydependentofspecific
hydrologyforbreeding.Holland(2002)foundthatborealtoadtadpolesinColoradoexperienced
thatgreatestlarvalgrowthratesatbreedingsiteswiththewarmestandleastvariablewater
temperatures.Timingofbreedingandtimeforlarvaldevelopmentcouldalsobeimpactedby
changesinhydrologicallevels(Corn2005).
C2c)Dependenceonaspecificdisturbanceregimelikelytobeimpactedbyclimatechange.
Neutral.Theborealtoadisnotdependentuponspecificdisturbanceregimessuchasfires,floods,
severewinds,pathogenoutbreaks,orsimilarevents.
C2d)Dependenceonice,ice‐edge,orsnowcoverhabitats.Somewhatincrease.Borealtoad
breedingpondsoftendependonsnowpackmelttomaintainwaterlevelsforbreeding.Depthof
Snowpackcanbeimportantinprotectinghibernatingtoadsfromfreezing(Campbell1970;Corn
2003;Schereretal.2005).
C3)Restrictiontouncommongeologicalfeaturesorderivatives.Neutral.Borealtoadsarenot
dependentonanyspecificgeologicfeature.
C4a)Dependenceonotherspeciestogeneratehabitat.Increase.Borealtoadbreedingponds
arecommonlyfoundinbeaverpondcomplexes(Hammerson1999;Holland2002)andareoften
dependentonbeaverstomaintainbreedinghabitat.
C4b)Dietaryversatility(animals).Neutral.Borealtoadsfeedonawidevarietyofinvertebrates
(Hammerson1999).
C4d)Dependenceonotherspeciesforpropaguledispersal.Neutral.Theborealtoadisaself‐
disperser.
C4e)FormspartofaninterspecificinteractionnotcoveredbyC4a‐d.Neutral.Noother
interspecificinteractionsareimportanttothepersistenceoftheborealtoad.
C5a)Measuredgeneticvariation.Somewhatdecrease.Switzeretal.(2009)foundpatternsof
highlevelsofgeneticdifferentiationamongrelativelyclosebreedingsitesofborealtoadsandfound
thepopulationswithinthesouthernRockyMountainstobeisolatedwithlimitedgeneflowamong
populations.
C5b)Occurrenceofbottlenecksinrecentevolutionaryhistory.Neutral.Thereisnoevidence
thatthetotalpopulationofborealtoadswerereducedto<1000individualsortheoccupiedarea
wasreducedby>30%overthelast500years.
186ColoradoNaturalHeritageProgram©2015
C6)Phenologicalresponsetochangingseasonaltemperatureandprecipitationdynamics.
Neutral.Theeffectsofchangesintemperatureandprecipitationmayhavealargeeffectonthe
timingofbreedingforamphibians(Corn2005)andhasbeenobservedinsomespecies(Blaustein
etal.2001).
Literature Cited
Adams,S.B.,D.S.Schmetterling,andM.K.Young.2005.Instreammovementsbyborealtoads.HerpetologicalReview
36(1):27‐33.
Blaustein,A.R.,L.K.Belden,D.H.Olson,D.M.Green,T.L.Root,andJ.M.Kiesecker.2001.Amphibianbreedingandclimate
change.ConservationBiology15:1804‐1809.
Campbell,J.B.1970.Life‐historyofBufoboreasboreasintheColoradoFrontRange.Ph.D.thesis,UniversityofColorado,
Boulder,CO.
Corn,P.S.2003.Amphibianbreedingandclimatechange:Importanceofsnowinthemountains.ConservationBiology
17(2):622‐625.
Corn,P.S.2005.Climatechangeandamphibians.AnimalBiodiversityandConservation28(1):59‐67.
ColoradoNaturalHeritageProgram(CNHP).2014.BiodiversityTrackingandConservationSystem(BIOTICS).Colorado
NaturalHeritageProgram,ColoradoStateUniversity,FortCollins,CO.
Hammerson,G.A.1999.AmphibiansandreptilesinColorado.Seconded.UniversityPressofColoradoandColorado
DivisionofWildlife.
Holland,A.A.2002.EvaluatingBorealToad(Bufoboreas)BreedingHabitatSuitability.M.S.Thesis,ColoradoState
University,FortCollins,CO.
Jones,M.S.,J.P.Goettl,K.L.Scherff‐Norris,S.Brinkman,L.J.Livo,A.M.Goebel.1998.ColoradoDivisionofWildlifeBoreal
ToadResearchProgressReport1995‐1997.UnpublishedreportColoradoDivisionofWildlife,Denver,CO.
Lambert,B.andS.Schneider.2013.ColoradoNaturalHeritageProgramborealtoadsurveyandmonitoringproject
summary1999‐2012.UnpublishedreporttotheColoradoDivisionofWildlife,FortCollins,CO.
Loeffler,C.(ed.),2001.ConservationplanandagreementforthemanagementandrecoveryofthesouthernRocky
Mountainpopulationoftheborealtoad(Bufoboreasboreas),BorealToadRecoveryTeam.76pp.+appendices.
NatureServe2012.ClimateChangeVulnerabilityAssessmentTool,version2.1.Availableonlineat
https://connect.natureserve.org/science/climate‐change/ccvi.
NatureServe.2014.NatureServeExplorer:Anonlineencyclopediaoflife[webapplication].Version7.1.NatureServe,
Arlington,Virginia.Availablehttp://explorer.natureserve.org.Accessed2014.
Scherer,R.D.,E.Muths,B.R.Noon,andP.S.Corn.2005.Anevaluationofweatheranddiseaseascausesofdeclineintwo
populationsofborealtoads.EcologicalApplications15(6):2150‐2160.
Switzer,J.F.,R.Johnson,B.A.Lubinski,andT.L.King.2009.GeneticstructureintheAnaxyrusboreasspeciesgroup(Anura,
Bufonidae):anevaluationoftheSouthernRockyMountainspopulation.FinalReportSubmittedtotheU.S.Fishand
WildlifeService.

ClimateChangeVulnerabilityAssessmentforColoradoBLM187
Canyon Treefrog
Hylaarenicolor
G5/S2
Family:Hylidae
Climate Vulnerability Rank: Moderately Vulnerable
ThisColoradostate‐widerankisbasedon:themajorityofcanyontreefrogpopulationsinColorado
beingrestrictedtorockycanyonsandcanyon‐bottompoolsthatactasnaturalbarriers,whichcould
limittheabilityofthisspeciestoshiftitsrangeinresponsetoclimatechange;Thecanyontreefrog
ishighlydependentonspecifichydrology(rainfall)forbreedingandthepotentialdisruptionofthe
timingofbreedingandlarvaldevelopmentbyclimatechangeisaconcern.
Distribution:CanyontreefrogsoccurinwesternColoradoatelevationsrangingfromabout4,500‐
6,300ft.alongthesouthernedgeoftheColoradoRivervalleyandalongtheDoloresRiverandits
tributariessouthtoSanMiguelCounty,(Hammerson1999).ThereisanisolatedpopulationinLas
AnimasCountyatMesadeMaya(CNHP2014).Habitat:Canyontreefrogsarefoundalong
intermittentstreamsindeeprockycanyons(Hammerson1999).
CCVI Scoring
Temperature:CalculatedusingClimateWizard:ensembleaverage,highemissionscenario(A2),
mid‐centurytimeframe,averageannualchange.InColoradobymid‐centurythisspeciesisexpected
tobeexposedtomeanannualtemperatureincreasesof5.0oFto5.5oFover100percentofitsrange
(NatureServe2012).
Moisture:CalculatedinGISusingNatureServeHamonAET:PETmoisturemetricdata(thisindex
integratesprojectedtemperatureandprecipitationchangestoindicatehowmuchdryingwilltake
place).Rangewidethisspeciesispredictedtobeexposedtonetdryingofgreaterthan11.9percent
on12.1percentofitsrange,9.7to11.9percentdryingon43.2percentofitsrangeand7.4to9.6
Photo:CopyrightbyLaurenJ.Livoand
SteveWilcox
188ColoradoNaturalHeritageProgram©2015
percentdryingon31.3percentofitsrangeand5.1to7.3percentdryingon13percentofitsrange
(NatureServe2012).
B1)Exposuretosealevelrise.Neutral.
B2a)Distributionrelativetonaturalbarriers.Somewhatincreasevulnerability.InColorado,
thisspeciesisrestrictedtorockycanyonsandbreedsincanyonbottompools(Hammerson1999).
Geneticanalysissuggeststhatgeographicbarriersareresponsibleforphylogeographicpatternsin
canyontreefrogsfromArizonaandNewMexico(Barber1999).
B2b)Distributionrelativetoanthropogenicbarriers.Neutral.Intensiveresidentialor
commercialdevelopmentandhightrafficvolumehighwayscouldbeconsideredasanthropogenic
barriers(NatureServe2014).Themajorityofcanyontreefrogpopulationsoccuronfederally
managedlandsindeepcanyonswheredevelopmentisverylow.
B3)Impactoflandusechangesresultingfromhumanresponsestoclimatechange.Neutral.
Landalterationssuchas,timberharvest,grazing,recreationandwaterdevelopmentwouldlikely
notbebeneficialforcanyontreefroghabitat,buttheremotenessofoccurrencesmakesitunlikely
areasforfuturehumandisturbances.Landusechangesassociatedwithclimatechangemaybe
consideredathreatbutthescopeandtypeofchangeintherangeofthecanyontreefrogishardto
predict.
C1)Dispersalandmovements.Neutral.Canyontreefrogsaredependentonrockycanyonslopes
andbottomsforbreeding,foragingandhibernatinghabitat(Hammerson1999).Hylidsgenerally
exhibitlimitedmovementsonashort‐termbasis(NatureServe2014).Exceptforwarmrainy
nights,canyontreefrogsdonotrangefarfromcanyon‐bottompools(Hammerson1999).
C2ai)Predictedsensitivitytotemperature:historicthermalniche.Neutral.Therangeoccupied
bythecanyontreefrogintheassessedareahasexperiencedaverage(57.1‐77°F/31.8‐43°C)
meanseasonaltemperaturevariationinthelast50years.
C2aii)Predictedsensitivitytotemperature:physiologicalthermalniche.Somewhatdecrease.
Thisspeciesshowsapreferenceforenvironmentswithwarmertemperatures(Synderand
Hammerson1993).
C2bi) Predictedsensitivitytochangesinprecipitation,hydrology,ormoistureregime:
historicalhydrologicalniche.Neutral.Thisspecieshasundergoneaverage(21‐40inches/509‐
1,016mm)precipitationvariationoverthelast50years.
C2bii)Predictedsensitivitytochangesinprecipitation,hydrology,ormoistureregime:
physiologicalhydrologicalniche.Increase.Thecanyontreefrogishighlydependentonspecific
hydrology(rainfall)forbreeding(Hammerson1999).
C2c)Dependenceonaspecificdisturbanceregimelikelytobeimpactedbyclimatechange.
Neutral.Thecanyontreefrogisnotdependentuponspecificdisturbanceregimessuchasfires,
floods,severewinds,pathogenoutbreaks,orsimilarevents.
ClimateChangeVulnerabilityAssessmentforColoradoBLM189
C2d)Dependenceonice,ice‐edge,orsnowcoverhabitats.Neutral.Canyontreefrogsdonot
dependoniceorsnow‐coverhabitats.
C3)Restrictiontouncommongeologicalfeaturesorderivatives.Somewhatincrease.Canyon
treefrogsareassociatedwithrockycanyonbottomswheretheyperchonsolidrocksurfacesandat
nightretreattorockcrevices(Hammerson1999).
C4a)Dependenceonotherspeciestogeneratehabitat.Neutral.Canyontreefrogsdonotrelyon
otherspeciestogeneratehabitat.
C4b)Dietaryversatility(animals).Neutral.Canyontreefrogsfeedonawidevarietyof
invertebrates(Hammerson1999).
C4d)Dependenceonotherspeciesforpropaguledispersal.Neutral.Thecanyontreefrogisa
self‐disperser.
C4e)FormspartofaninterspecificinteractionnotcoveredbyC4a‐d.Neutral.Noother
interspecificinteractionsareimportanttothepersistenceofthecanyontreefrog.
C5a)Measuredgeneticvariation.Somewhatincrease.Barber(1999)foundlowgeneticvariation
fromdifferencesamongpopulationsinArizonaandNewMexico.
C5b)Occurrenceofbottlenecksinrecentevolutionaryhistory.Neutral.Thereisnoevidence
thatthetotalpopulationofcanyontreefrogswerereducedto<1000individualsortheoccupied
areawasreducedby>30%overthelast500years.
C6)Phenologicalresponsetochangingseasonaltemperatureandprecipitationdynamics.
Neutral.Theeffectsofchangesintemperatureandprecipitationmayhavealargeeffectonthe
timingofbreedingforamphibians(Blausteinetal.2001;Corn2005),buthasnotbeenreportedfor
canyontreefrogs.
Literature Cited
Barber,P.H.1999.Patternsofgeneflowandpopulationgeneticstructureinthecanyontreefrog,Hylaarenicolor.
MolecularEcology8:563‐576.
Blaustein,A.R.,L.K.Belden,D.H.Olson,D.M.Green,T.L.Root,andJ.M.Kiesecker.2001.Amphibianbreedingandclimate
change.ConservationBiology15:1804‐1809.
ColoradoNaturalHeritageProgram(CNHP).2014.BiodiversityTrackingandConservationSystem(BIOTICS).Colorado
NaturalHeritageProgram,ColoradoStateUniversity,FortCollins,CO.
Corn,P.S.2005.Climatechangeandamphibians.AnimalBiodiversityandConservation28(1):59‐67.
Hammerson,G.A.1999.AmphibiansandreptilesinColorado.Seconded.UniversityPressofColoradoandColorado
DivisionofWildlife.
NatureServe2012.ClimateChangeVulnerabilityAssessmentTool,version2.1.Availableonlineat
https://connect.natureserve.org/science/climate‐change/ccvi.
190ColoradoNaturalHeritageProgram©2015
NatureServe.2014.NatureServeExplorer:Anonlineencyclopediaoflife[webapplication].Version7.1.NatureServe,
Arlington,Virginia.Availablehttp://explorer.natureserve.org.Accessed2014.
Snyder,G.K.andG.A.Hammerson.1993.Interrelationshipsbetweenwatereconomyandthermoregulationinthecanyon
treefrogHylaarenicolor.JournalofAridEnvironments25:321‐329.

ClimateChangeVulnerabilityAssessmentforColoradoBLM191
Great Basin Spadefoot
Speaintermontana
G5/S3
Family:Scaphiopodidae
Climate Vulnerability Rank: Not Vulnerable/Presumed Stable
ThisColoradostate‐widerankisbasedon:Theonlymetricthatincreasedthevulnerabilityfor
GreatBasinspadefootswastheirdependenceonspecifichydrology(ephemeralandpermanent
watersources)forbreedingandthepotentialdisruptionofthetimingofbreedingandlarval
developmentbyclimatechange.Therestofthescoringfactorswereneutral.Thehabitatthis
speciesinhabitsisdiverseanddevoidofnaturalbarriers;withintherangeofthisspeciesin
Colorado,oilandgasdevelopmentcouldimpacthabitat,buttherehasnotbeenanyevidenceofthat
occurring.Irrigatedagriculturemaybebeneficialincreatingbreedinghabitat(Leonardetal.1996).
GreatBasinspadefootsoccurinprettyremoteareasofColoradoandareatalowriskofthreats
fromurbandevelopment.
Distribution:GreatBasinspadefootsoccurinnorthwesternColorado,northoftheUncompahgre
Plateau(Hammerson1999).Habitat:GreatBasinspadefootsarefoundinwidevarietyofhabitats
inColoradoatelevationsbelow7,000ft.(Hammerson1999).TypicalhabitattypesinColoradofor
GreatBasinspadefootsarepinyon‐juniperwoodlands,sagebrushandsemidesertshrublands
(Hammerson1999).Breedingoccursintemporarypoolsfromheavyrains(Hammerson1999)and
occasionallyinpermanentshallowponds(Hovinghetal.1995).
CCVI Scoring
Temperature:CalculatedusingClimateWizard:ensembleaverage,highemissionscenario(A2),
mid‐centurytimeframe,averageannualchange.InColoradobymid‐centurythisspeciesisexpected
tobeexposedtomeanannualtemperatureincreasesof5.0oFto5.5oFover100percentofitsrange
(NatureServe2012).
Photo:CopyrightbyLaurenJ.
LivoandSteveWilcox
192ColoradoNaturalHeritageProgram©2015
Moisture:CalculatedinGISusingNatureServeHamonAET:PETmoisturemetricdata(thisindex
integratesprojectedtemperatureandprecipitationchangestoindicatehowmuchdryingwilltake
place).Rangewidethisspeciesispredictedtobeexposedtonetdryingofgreaterthan11.9percent
on9.1percentofitsrange,9.7to11.9percentdryingon55.1percentofitsrangeand7.4to9.6
percentdryingon22.6percentofitsrangeand5.1–7.3on12.7percentofitsrange(NatureServe
2012).
B1)Exposuretosealevelrise.Neutral.
B2a)Distributionrelativetonaturalbarriers.Neutral.InColorado,thisspeciesinhabits
sagebrushflats,pinyon‐juniperwoodlandandsemi‐desertshrublands(Hammerson1999),areas
thataretypicallydevoidofnaturalbarriersforspadefoottoads.
B2b)Distributionrelativetoanthropogenicbarriers.Neutral.Intensiveresidentialor
commercialdevelopmentandhightrafficvolumehighwayscouldbeconsideredasanthropogenic
barriers(NatureServe2014),butformostoftheGreatBasinspadefootsrangeinColoradourban
developmentislow.Theremaybebreedinghabitatcreationfromirrigatedagriculture,butinsome
casesgrainfieldscouldeliminatebreedingponds(Leonardetal.1996).
B3)Impactoflandusechangesresultingfromhumanresponsestoclimatechange.Neutral.
Landalterationssuchas,timberharvest,grazing,recreationandwaterdevelopmentwouldlikely
notbebeneficialforGreatBasinspadefoots,buttheremotenessofoccurrencesmakesitunlikely
areasforfuturehumandisturbances.Landusechangesassociatedwithclimatechangemaybe
consideredathreatbutthescopeandtypeofchangeintherangeofthecanyontreefrogishardto
predict.
C1)Dispersalandmovements.Neutral.GreatBasinspadefootsaredependenton
sagebrush/semi‐desertshrublandhabitatwithtemporarypoolsforbreedingandforaging
(Hammerson1999).Specificdispersaldataforthisspeciesislackingbutingeneralspadefoottoads
exhibithighfidelitytobreedingsitewithmovementsuptoseveralhundredmetersfrombreeding
sites(NatureServe2014).Therehavebeenreportsofadultsmigratingupto100metersbetween
breedingpoolsandnon‐breedinghabitat(Busecketal.2005).
C2ai)Predictedsensitivitytotemperature:historicthermalniche.Neutral.Therangeoccupied
bytheborealtoadintheassessedareahasexperiencedaverage(57.1‐77°F/31.8‐43°C)mean
seasonaltemperaturevariationinthelast50years.
C2aii)Predictedsensitivitytotemperature:physiologicalthermalniche.Neutral.Thisspecies
isnotrestrictedtocoldenvironmentsthatarevulnerabletoclimatechange.
C2bi) Predictedsensitivitytochangesinprecipitation,hydrology,ormoistureregime:
historicalhydrologicalniche.Neutral.Thisspecieshasundergoneaverage(21‐40inches/509‐
1,016mm)precipitationvariationoverthelast50years.
C2bii)Predictedsensitivitytochangesinprecipitation,hydrology,ormoistureregime:
physiologicalhydrologicalniche.Increase.Thegreatbasinspadefootishighlydependenton
ClimateChangeVulnerabilityAssessmentforColoradoBLM193
specifichydrology(ephemeralandpermanentwatersources)forbreeding(Hovinghetal.1995;
Hammerson1999;Busecketal.2005).Timingofbreedingandtimeforlarvaldevelopmentin
amphibianscouldalsobeimpactedbychangesinhydrologicallevels(Corn2005).
C2c)Dependenceonaspecificdisturbanceregimelikelytobeimpactedbyclimatechange.
Neutral.Thegreatbasinspadefootisnotdependentuponspecificdisturbanceregimessuchas
fires,floods,severewinds,pathogenoutbreaks,orsimilarevents.
C2d)Dependenceonice,ice‐edge,orsnowcoverhabitats.Neutral.GreatBasinspadefootsdo
notdependoniceorsnow‐coverhabitats.
C3)Restrictiontouncommongeologicalfeaturesorderivatives.Neutral.GreatBasin
spadefootsarenotdependentonanyspecificgeologicfeature.
C4a)Dependenceonotherspeciestogeneratehabitat.Neutral.GreatBasinspadefootsdonot
relyonotherspeciestogeneratehabitat.
C4b)Dietaryversatility(animals).Neutral.GreatBasinspadefootsfeedonawidevarietyof
invertebrates(Hammerson1999).
C4d)Dependenceonotherspeciesforpropaguledispersal.Neutral.TheGreatBasinspadefoot
isaself‐disperser.
C4e)FormspartofaninterspecificinteractionnotcoveredbyC4a‐d.Neutral.Noother
interspecificinteractionsareimportanttothepersistenceoftheGreatBasinspadefoot.
C5a)Measuredgeneticvariation.Neutral.PhylogeneticanalysisontwopopulationsofGreat
Basinspadefootssuggestedpossiblegeographicvariationwithinthespecies(WiensandTitus
1991).
C5b)Occurrenceofbottlenecksinrecentevolutionaryhistory.Neutral.Thereisnoevidence
thatthetotalpopulationofGreatBasinspadefootswerereducedto<1000individualsorthe
occupiedareawasreducedby>30%overthelast500years.
C6)Phenologicalresponsetochangingseasonaltemperatureandprecipitationdynamics.
Neutral.Theeffectsofchangesintemperatureandprecipitationmayhavealargeeffectonthe
timingofbreedingforamphibians(Corn2005)andhasbeenobservedinsomespecies(Blaustein
etal.2001).
Literature Cited
Blaustein,A.R.,L.K.Belden,D.H.Olson,D.M.Green,T.L.Root,andJ.M.Kiesecker.2001.Amphibianbreedingandclimate
change.ConservationBiology15:1804‐1809.
Buseck,R.S.,D.A.Keinath,andM.Geraud.2005.SpeciesAssessmentforGreatBasinSpadefootToad(Speaintermontana)
inWyoming.TechnicalreportforBureauofLandManagement,Cheyenne,Wyoming.
Corn,P.S.2005.Climatechangeandamphibians.AnimalBiodiversityandConservation28(1):59‐67.
194ColoradoNaturalHeritageProgram©2015
Hammerson,G.A.1999.AmphibiansandreptilesinColorado.Seconded.UniversityPressofColoradoandColorado
DivisionofWildlife.
Hovingh,P.,B.Benton,andD.Bornholdt.1995.Aquaticparametersandlifehistoryobservationsofthegreatbasin
spadefoottoadinUtah.GreatBasinNaturalist45:22‐30.
Leonard,W.P,H.A.Brown,LL.C.Jones,K.R.McAllisterandR.M.Storm.1996.AmphibiansofWashingtonandOregon.
SeattleAudubonSociety,Seattle,Washington.
NatureServe2012.ClimateChangeVulnerabilityAssessmentTool,version2.1.Availableonlineat
https://connect.natureserve.org/science/climate‐change/ccvi.
NatureServe.2014.NatureServeExplorer:Anonlineencyclopediaoflife[webapplication].Version7.1.NatureServe,
Arlington,Virginia.Availablehttp://explorer.natureserve.org.Accessed2014.
Wiens,J.J.andT.A.Titus.1991.AphylogeneticanalysisofSpea(Anura:Pelobatidae).Herpetologica.47(1):21‐28.

ClimateChangeVulnerabilityAssessmentforColoradoBLM195
Northern Leopard Frog
Lithobatespipiens
G5/S3
Family:Ranidae
Climate Vulnerability Rank: Moderately Vulnerable
ThisColoradostate‐widerankisbasedon:thenorthernleopardfrog’sdependenceonspecific
hydrologyforbreedingandthepotentialdisruptionofthetimingofbreedingandlarval
developmentbyclimatechange.ThepredictedeffectsofclimatechangeintheWestincludea
reducedsnowpackandshorterperiodsofsnowcover,snowmeltthatoccursearlierintheseason,a
hydrologiccyclethatismoredynamicasextremerainfalleventsoccurwithgreaterfrequencyand
anoverallwarmer,drier,andmoredrought‐likeconditions(Melilloetal.2014).Climatechangehas
thepotentialtoalterthetimingofpondbreedingamphibians(Blausteinetal.2001).Additional
importantrankingfactorsincludethevulnerabilityofnorthernleopardfrogstodevelopmentand
habitatfragmentationfrombusypavedroads.
Distribution:NorthernleopardfrogsoccurthroughoutColorado,excludingmostofthe
southeasternandeasteast‐centralportionofthestate(Hammerson1999).Habitat:Northern
leopardfrogsarefoundinwidevarietyofhabitatsinColoradoatelevationsrangingfrom3,500ft.
to11,000ft.(Hammerson1999).TypicallyinColorado,northernleopardfrogsarefoundinwet
meadows,marshes,ponds,streams,lakesandreservoirs.Breedingoccursinmid‐sizedponds
(Merrell1997)andshallowareasofpermanentpondsandinseasonallyfloodedareasadjacentto
permanentpoolsorstreams(Hammerson1999).
CCVI Scoring
Temperature:CalculatedusingClimateWizard:ensembleaverage,mediumemissionscenario
(A1B),mid‐centurytimeframe,averageannualchange.InColoradobymid‐centurythisspeciesis
expectedtobeexposedtomeanannualtemperatureincreasesof5.0oFto5.5oFover100percentof
itsrange(NatureServe2012).
196ColoradoNaturalHeritageProgram©2015
Moisture:CalculatedinGISusingNatureServeHamonAET:PETmoisturemetricdata(thisindex
integratesprojectedtemperatureandprecipitationchangestoindicatehowmuchdryingwilltake
place).Rangewidethisspeciesispredictedtobeexposedtonetdryingofgreaterthan11.9percent
on12.6percentofitsrange,9.7to11.9percentdryingon52.8percentofitsrangeand7.4to9.6
percentdryingon29.1percentofitsrangeand5.1–7.3on5.4percentofitsrange(NatureServe
2012).
B1)Exposuretosealevelrise.Neutral.
B2a)Distributionrelativetonaturalbarriers.Neutral.Thenorthernleopardfrogoccupiesa
varietyofhabitattypesandiswidelydistributedinColorado(Hammerson1999).Whilepatchiness
occurs,therearefewnaturalbarrierstotheirdispersaltootherlandscapes.Riverscouldbea
barrierdependingonwidthandflowdynamics(NatureServe2014).
B2b)Distributionrelativetoanthropogenicbarriers.Somewhatincrease.Intensiveresidential
orcommercialdevelopmentandhightrafficvolumehighwayscouldbeconsideredas
anthropogenicbarriers(NatureServe2014).Disturbedareasdevoidofcoverdisruptedtheability
fornorthernleopardfrogstoreachhabitatpatchesinNewBrunswick(MazerolleandDesrochers
(2005).Bouchardetal.(2009)foundthatleopardfrogswerehighlyvulnerabletoroadmortality.
B3)Impactoflandusechangesresultingfromhumanresponsestoclimatechange.
Somewhatincreasetoneutral.ThenortheasternColoradohabitatofthisspeciesissusceptibleto
potentialdevelopmentofwindfarms/solarfarmsandbiofuelsproduction.Inthefaceofrising
climatechangeandcoststoextractfossilfuels,windenergydevelopmentisexpectedtoincrease
withintherangeofthenorthernleopardfroginColorado(NRDC2014).
C1)Dispersalandmovements.Somewhatdecreasetoneutral.Northernleopardfrogshavegood
movementanddispersalcapabilityastheyaredependentuponbreeding,foragingandhibernating
habitat,whichencompassesbothwetlandanduplandhabitat(Hammerson1999;NatureServe
2014).Theevidenceshowsseasonalvariabilityinleopardfrogmovementsandindividual
movementsupto4kmforadults(Seburnetal.1997)and5.2kmforjuveniles(Dole1971)in
AlbertaandMichiganrespectively.
C2ai)Predictedsensitivitytotemperature:historicthermalniche.Neutral.Therangeoccupied
bytheborealtoadintheassessedareahasexperiencedaverage(57.1‐77°F/31.8‐43°C)mean
seasonaltemperaturevariationinthelast50years.
C2aii)Predictedsensitivitytotemperature:physiologicalthermalniche.Increase.Somewhat
Increase.TherangeofthisspeciesinColoradoincludessomehigherelevationmontaneareas.
Reducedsnowfallandincreasedsummerevaporationcouldhavedramaticeffectsontheduration
oroccurrenceofseasonalwetlands(Corn2005).
C2bi) Predictedsensitivitytochangesinprecipitation,hydrology,ormoistureregime:
historicalhydrologicalniche.Somewhatdecrease.Thisspecieshasundergonegreaterthan
average(>40inches/1,016mm)precipitationvariationoverthelast50years.
ClimateChangeVulnerabilityAssessmentforColoradoBLM197
C2bii)Predictedsensitivitytochangesinprecipitation,hydrology,ormoistureregime:
physiologicalhydrologicalniche.Increase.Thenorthernleopardfrogishighlydependenton
specifichydrologyforbreeding.Reproductivesuccessistiedtoappropriatetemperaturein
breedingsites(shallowponds);timingofthiswouldchangewithearlysnowmeltandwarmer
temperatures(SmithandKeinath2007).Timingofbreedingandtimeforlarvaldevelopmentcould
alsobeimpactedbychangesinhydrologicallevels(Corn2005).Increaseddroughtcouldcause
reductionsinhabitatandpotentiallyincreasemortalityfromeggtoadult.Droughtwasresponsible
fortheextirpationofapopulationofleopardfrogsinLarimerCounty,Colorado(Cornand
Fogleman1984).
C2c)Dependenceonaspecificdisturbanceregimelikelytobeimpactedbyclimatechange.
Neutral.Thenorthernleopardfrogisnotdependentuponspecificdisturbanceregimessuchas
fires,floods,severewinds,pathogenoutbreaks,orsimilarevents.
C2d)Dependenceonice,ice‐edge,orsnowcoverhabitats.Neutral.Northernleopardfrogs
inhabitawiderangeofhabitats.
C3)Restrictiontouncommongeologicalfeaturesorderivatives.Neutral.Northernleopard
frogsarenotdependentonanyspecificgeologicfeature.
C4a)Dependenceonotherspeciestogeneratehabitat.Neutraltosomewhatincrease.Northern
leopardfrogssometimesusebeaverpondsforbreeding(Hammerson1999).
C4b)Dietaryversatility(animals).Neutral.Northernleopardfrogsfeedonawidevarietyof
invertebrates(Hammerson1999).
C4d)Dependenceonotherspeciesforpropaguledispersal.Neutral.Thenorthernleopardfrog
isaself‐disperser.
C4e)FormspartofaninterspecificinteractionnotcoveredbyC4a‐d.Neutral.Noother
interspecificinteractionsareimportanttothepersistenceofthenorthernleopardfrog.
C5a)Measuredgeneticvariation.Somewhatdecrease.Mushetetal.(2013)foundhighlevelsof
geneticdiversityinpopulationsofnorthernleopardfrogsinNorthDakota.
C5b)Occurrenceofbottlenecksinrecentevolutionaryhistory.Neutral.Thereisnoevidence
thatthetotalpopulationofnorthernleopardfrogswerereducedto<1000individualsorthe
occupiedareawasreducedby>30%overthelast500years.
C6)Phenologicalresponsetochangingseasonaltemperatureandprecipitationdynamics.
Neutral.Theeffectsofchangesintemperatureandprecipitationmayhavealargeeffectonthe
timingofbreedingforamphibians(Corn2005)andhasbeenobservedinsomespecies(Blaustein
etal.2001).
Literature Cited
Alford,RossA.2011.Bleakfutureforamphibians.Nature480:461‐462.
198ColoradoNaturalHeritageProgram©2015
Blaustein,A.R.,L.K.Belden,D.H.Olson,D.M.Green,T.L.Root,andJ.M.Kiesecker.2001.Amphibianbreedingandclimate
change.ConservationBiology15:1804‐1809.
Bouchard,J.,A.T.Ford,F.E.Eigenbrod,andL.Fahrig.2009.Behavioralresponsesofnorthernleopardfrogs(Ranapipiens)
toroadsandtraffic:Implicationsforpopulationpersistence.EcologyandSociety14(2):23.
Corn,P.S.andJ.C.Fogleman.1984.Extinctionofmontanepopulationsofthenorthernleopardfrog(Ranapipiens)in
Colorado.JournalofHerpetology18(2):147‐152.
Corn,P.S.2005.Climatechangeandamphibians.AnimalBiodiversityandConservation28(1):59‐67.
Dole,J.W.1971.Dispersalofrecentlymetamorphosedleopardfrogs,Ranapipiens.Copeia1971:221‐228.
Hammerson,G.A.1999.AmphibiansandreptilesinColorado.Seconded.UniversityPressofColoradoandColorado
DivisionofWildlife.
Mazerolle,M.J.andA.Desrochers.2005.Landscaperesistancetofrogmovements.CanadianJournalofZoology83:455‐
464.
Melillo,J.M.,T.C.Richmond,andG.W.Yohe,Eds.2014.ClimateChangeImpactsintheUnitedStates:TheThirdNational
ClimateAssessment.U.S.GlobalChangeResearchProgram,841pp.doi:10.7930/J0Z31WJ2.
Merrell,D.J.1977.Lifehistoryoftheleopardfrog,Ranapipiens,inMinnesota.BellMuseumofNaturalHistoryOccasional
PapersNo.15:1‐23.
Mushet,D.M.,N.H.Euliss,Y.ChenandC.A.Stockwell.2013.Complexspatialdynamicsmaintainnorthernleopardfrog
(Lithobatespipiens)geneticdiversityinatemporaryvaryinglandscape.HerpetologicalConservationandBiology
8(1):163‐175.
NaturalResourceDefenseCouncil[NRDC].2014.RenewableEnergyforAmerica,harvestingthebenefitsofhomegrown
renewableenergy[Online].http://www.nrdc.org/energy/renewables/technologies.asp
NatureServe2012.ClimateChangeVulnerabilityAssessmentTool,version2.1.Availableonlineat
https://connect.natureserve.org/science/climate‐change/ccvi.
NatureServe.2014.NatureServeExplorer:Anonlineencyclopediaoflife[webapplication].Version7.1.NatureServe,
Arlington,Virginia.Availablehttp://explorer.natureserve.org.Accessed2014.
Seburn,C.N.L.,D.C.SeburnandC.A.Paszkowski.1997.Northernleopardfrog(Ranapipiens)dispersalinrelationto
habitat.Pp.64‐72inGreen,D.M.,ed.AmphibiansinDecline:CanadianStudiesofaGlobalProblem.SocietyfortheStudy
ofAmphibiansandReptiles,HerpetologicalConservationNumberOne.St.Louis,Missouri.
Smith,B.E.andD.A.Keinath.2007.NorthernLeopardFrog(Ranapipiens):atechnicalconservationassessment.[Online].
USDAForestService,RockyMountainRegion.Available:http://www.fs.fed.us/r2/
projects/scp/assessments/northernleopardfrog.pdf
ClimateChangeVulnerabilityAssessmentforColoradoBLM199
American Peregrine Falcon
Falcoperegrinusanatum
G4T4/S2B
Family:Falconidae
Climate Vulnerability Rank: Not Vulnerable/Presumed Stable
ThisColoradostatewiderankisbasedon:theextensivedispersalandmigratoryabilitiesofthis
raptor,thelackofimpactsfromlandusechangesassociatedwithclimatechange,theaverage
geneticvariationmeasuredforthespeciesinNorthAmerica,andthepredicted68percent
expansionofthePeregrinefalconswinterrangeinresponsetoclimatechange.Climatemodels
projectincreasedwarminganddroughtacrosstheassessedareawithannualaveragetemperatures
risingby2.5°Fto5.5°Fby2041‐2070andby5.5°Fto9.5°Fby2070‐2099withcontinuedgrowth
inglobalemissions(A2emissionsscenario),withthegreatestincreasesinthesummerandfall
(Melilloetal.2014).Projectionsofprecipitationchangesarelesscertain,butunderacontinuation
ofcurrentrisingemissionstrends(A2),reducedwinterandspringprecipitationisconsistently
projectedforthesouthernpartoftheSouthwestby2100(Melilloetal.2014).Theseprojected
changesinclimatearenotexpectedtohaveimportantnegativeimpactstothePeregrinefalcon
withintheassessmentarea.
Distribution:PeregrineFalconsbreedalongthefoothillsofColorado'sFrontRangeand(inhigher
concentrations)intherivervalleysandcanyonsoftheWesternSlope(Kingery1998).Habitat:
PeregrineFalconsnestonledgesofhighcliffsinthefoothillsandmountainsfrom4,500toover
9,000feet(1,388to2,776m)inelevation(U.S.FishandWildlifeService1984).Thesteepestand
mostinaccessiblelocationsonthetallestcliffsarepreferred;especiallythosethatofferflat,
protectedledgesatleast18incheswide,withsheerrockaboveandbelow(Johnsgard2009).In
Colorado,pinyon/juniperwoodlandoccursinthevicinityofabouthalfofallPeregrineFalconnest
sites,andponderosapinewoodlandorforestisfoundataboutone‐quarterofthesites(Kingery
1998).
200ColoradoNaturalHeritageProgram©2015
CCVI Scoring
B1)Exposuretosealevelrise.Neutral.
B2a)Distributionrelativetonaturalbarriers.Neutral.Significantnaturalbarriersdonotexist
forthisspecies.ThePeregrinefalconisavolantlongdistantmigratorthatcantraversemountain
rangesandlargebodiesofwater.
B2b)Distributionrelativetoanthropogenicbarriers.Increase.Neutral.Significant
anthropogenicbarriersdonotexistforthisspecies.Thisraptorisavolantspeciesthatcanflyover
oraroundpotentialanthropogenicbarriers.
B3)Impactoflandusechangesresultingfromhumanresponsestoclimatechange.Neutral.
AlthoughraptorsandPeregrinefalconshavebeenreportedtobeatriskofcollisionwithwind
turbinesanddisturbedbytheirconstructionduringbrooding(NHFG2005)duringmigrationonly
about10%oftheirrangeintheassessedareaissuitableforwindenergydevelopment(NRDC
2014).Thisisalowconcernfortheraptorwithintheassessedarea.
C1)Dispersalandmovements.Decrease.Althoughmalestendnottodispersefarfromtheirnatal
sites,femalesareknowntodisperse100sofkmfromnatalsites(Whiteetal.2002).Additionally,
PeregrinefalconshavelargehomerangeswithestimatesinColoradorangingfrom358–1,508km2
(EndersonandCraig1997).Finally,thePeregrinefalconislongdistantmigratorandcantravel
over10,000kilometersduringmigration(Whiteetal.2002).
C2ai)Predictedsensitivitytotemperature:historicalthermalniche.Neutral.Therange
occupiedbythePeregrinefalconintheassessedareahasexperiencedanaverage(51.7‐77°F/31.8
‐43.0°C)zonalmeanseasonaltemperatureoverthelast50years.
C2aii)Predictedsensitivitytotemperature:physiologicalthermalniche.Neutral.Thereisno
directevidencethatPeregrinesrequirecoolmicroclimatesfornesting.Theygenerallymakea
scrapeonaledgewithshading,sheltering,oroverhangs,andtrendtosouth‐orwest‐facing
orientationinhighlatitudesbutmorerandomdirectionsinlowerlatitudes.Presumablyorientation
orothermicro‐featuresofeyrieprotectyoungfromtemperatureextremes(Whiteetal.2002)
C2bi)Predictedsensitivitytochangesinprecipitation,hydrology,ormoistureregime:
historicalhydrologicalniche.Somewhatdecrease.TherangeoccupiedbythePeregrinefalconin
theassessedareahasexperiencedgreaterthanaverage(>40inches/1,016mm)precipitation
variationinthepast50years.
C2bii)Predictedsensitivitytochangesinprecipitation,hydrology,ormoistureregime:
physiologicalhydrologicalniche.Neutral.ThePeregrinefalconhasnodependenceonastrongly
seasonalhydrologicregimeand/oraspecificaquatic/wetlandhabitatorlocalizedmoistureregime
thatishighlyvulnerabletolossorreductionwithclimatechange.
ClimateChangeVulnerabilityAssessmentforColoradoBLM201
C2c)Dependenceonaspecificdisturbanceregimelikelytobeimpactedbyclimatechange.
Neutral.ThePeregrinefalconisnotdependentuponspecificdisturbanceregimessuchasfires,
floods,severewinds,pathogenoutbreaks,orsimilarevents.
C2d)Dependenceonsnow‐coveredhabitats.Neutral.ThePeregrinefalconisnotdependenton
habitatswithice,snow,oronsnowpack.
C3)Restrictiontouncommongeologicalfeaturesorderivatives.Somewhatincreaseto
increase.Peregrinefalconshavepreferencefornestingoncliffs,althoughtheywilluseartificial
structuressuchassmokestacksandbuildings(Whiteetal.2002).
C4a)Dependenceonotherspeciestogeneratehabitat.Neutral.ThePeregrinefalconisnot
dependentonanyotherspeciestocreatesuitablehabitatforitsexistence
C4b)Dietaryversatility.Neutral.Withintheassessedareaperegrinefalconsmainlyfeedonbirds
includingcolumbids(e.g.,Zenaida),swifts,andpasserines,butmayoccasionallyfeedonmammals,
amphibians,fish,andinsects(Whiteetal.2002).
C4d)Dependenceonotherspeciesforpropaguledispersal.Neutral.ThePeregrinefalconisa
self‐disperser.
C4e)Formspartofaninterspecificinteractionnotcoveredby4a‐d.Neutral.Noother
interspecificinteractionsareimportanttothepersistenceofthePeregrinefalcon.
C5a)Measuredgeneticvariation.Neutral.Theperegrinefalconexhibitsaveragegeneticdiversity
acrosspopulationsinNorthAmericawithobservedandexpectedheterozygositiesbeingnearly
equivalent(Johnsonetal.2010).
C5b)Occurrenceofbottlenecksinrecentevolutionaryhistory.Unknown.
C6)Phenologicalresponsetochangingseasonaltemperatureandprecipitationdynamics.
Unknown.
D1)Responsetorecentclimatechange.Unknown.
D2)Modeledfuturechangeinpopulationorrangesize.Decrease.Itisprojectedthattherewill
beadecreaseinathreattothePeregrinefalconswinterrangeduetoclimatechange.Rangewide,
modelspredictedtoincreaseby69%by2080inthefalconswinterrange(NAS2014).Thisincludes
predictionsofanexpansionofthewinterrangeintheassessedarea.Modelsoftheimpactof
climatechangeonthefalcon’spopulationsizearenotavailablefortheassessedarea.
D3)Overlapofmodeledfuturerangewithcurrentrange.Unknown.
D4)Protectedareas.Unknown.
202ColoradoNaturalHeritageProgram©2015
Literature Cited
Enderson,J.H.andG.R.Craig.1997.WiderangingbynestingPeregrinefalcons(Falcoperegrinus)determinedby
radiotelemetry.JournalofRaptorResearch,31:333‐338.
Johnsgard,P.A.2009.BirdsoftheGreatPlains–BreedingSpeciesandtheirDistribution:NewExpandedEdition(2009).
546p.Univ.ofNebr.Press,LincolnandLondon.
Johnson,J.A.,S.L.Talbot,G.K.Sage,K.K.Burnham,J.W.Brown,T.L.Maechtle,W.S.Seeger,M.A.Yates,B.AndersonandD.P.
Mondell.2010.PLoSone,5:1‐15.Available:
http://www.plosone.org/article/fetchObject.action?uri=info:doi/10.1371/journal.pone.0014042&representation=PDF
[2/5/2015].
Kingery,H.E.(editor)1998.Coloradobreedingbirdatlas.ColoradoBreedingBirdAtlasPartnership,Denver.Colorado.
Melillo,J.M.,T.C.Richmond,andG.W.Yohe,Eds.,2014:ClimateChangeImpactsintheUnitedStates:TheThirdNational
ClimateAssessment.U.S.GlobalChangeResearchProgram,841pp.doi:10.7930/J0Z31WJ2.
NationalAudubonSociety(NAS).2014.Audubon’sBirdsandClimateChangeReport:APrimerforPractitioners.National
AudubonSociety,NewYork.Contributors:GaryLangham,JustinSchuetz,CandanSoykan,ChadWilsey,TomAuer,Geoff
LeBaron,ConnieSanchez,TrishDistler.Version1.2.Available:http://climate.audubon.org/birds/perfal/peregrine‐falcon
[1/29/2015].
NewHampshireFishandGame(NHFG).2005.NewHampshirewildlifeactionplan.NewHampshireFishandGame
Department,Concord,NewHampshire.
NaturalResourcesDefenseCouncil(NRDC).2014.RenewableenergyforAmerica.Available:
http://www.nrdc.org/energy/renewables/energymap.asp[2/6/2015].
U.S.FishandWildlifeService1984.AmericanPeregrineFalconRecoveryPlan(RockyMountainSouthwestPopulations).
White,C.M.,N.J.Clum,T.J.CadeandW.GraingerHunt.2002.PeregrineFalcon(Falcoperegrinus),TheBirdsofNorth
AmericaOnline(A.Poole,Ed.).Ithaca:CornellLabofOrnithology;RetrievedfromtheBirdsofNorthAmericaOnline:
http://bna.birds.cornell.edu/bna/species/660.
ClimateChangeVulnerabilityAssessmentforColoradoBLM203
Black Swift
Cypseloidesniger
G4/S3B
Family:Apodidae

Climate Vulnerability Rank: Not Vulnerable/Presumed Stable
ThisColoradostate‐widerankisbasedonthefollowingfactors:1)fewtonobarrierstomovement;
2)associationwithwaterfallsfornestingthatmaybevulnerabletodryingunderprojected
increasesintemperatureduetoclimatechange.
Distribution:InColorado,BlackSwiftsbreedprimarilyintheSanJuanMountainswithpopulations
concentratedinthesouthwestcornerofthestate.BreedinglocationsarealsofoundintheSangre
deCristo,FlatTops,Gore,andFrontrangesnorthtonorthernRouttCounty(ColoradoBirdAtlas
Partnership1998;Levadetal.2008).Habitat:InColorado,BlackSwiftsnestonclifffaceswith
waterfallsandinsomecases,wetcaves(ColoradoBirdAtlasPartnership1998;Levadetal.2008).
Elevation:Nestinglocationsrangefrom6,640to11,680feetinelevation,withameanof9,957feet
(Levadetal.2008).
EcologicalSystem:Cliffandcanyon
CCVI Scoring
B1)Exposuretosealevelrise.Neutral.
B2a)Distributionrelativetonaturalbarriers.Neutral.Volant–nobarriers
B2b)Distributionrelativetoanthropogenicbarriers.Neutral.Volant–nobarriers
204ColoradoNaturalHeritageProgram©2015
B3)Impactoflandusechangesresultingfromhumanresponsestoclimatechange.Neutral.It
isunlikelythatanymitigation‐relatedlandusechangeswilloccurwithinthisspecies’rangewithin
Colorado.
C1)Dispersalandmovements.Decrease.BlackSwiftsbreedinColoradoandundertakelong,
seasonalmigrations.Dispersalabilityisgreat.
C2)Sensitivitytotemperatureandmoisturechanges.Thisspecies'closeassociationwith
waterfallsfornestsites(LowtherandCollins2002)greatlyincreasesitsvulnerability;this
associationwithinColoradoaffectsitsscoreinboththehydrologicandgeologicsections.
C2ai)Predictedsensitivitytotemperature:historicalthermalniche.Neutral
C2aii)Predictedsensitivitytotemperature:physiologicalthermalniche.Neutral.BlackSwifts
prefercoolsitesnearwaterfallsfornesting,butthesemicroclimatesarenotlikelytobeaffected
directlybyclimatechange.
C2bi)Predictedsensitivitytochangesinprecipitation,hydrology,ormoistureregime:
historicalhydrologicalniche.Neutral
C2bii)Predictedsensitivitytochangesinprecipitation,hydrology,ormoistureregime:
physiologicalhydrologicalniche.Increase.Thedegreetowhichstreamsonwhichthese
waterfallsarefoundwillbeaffectedbyclimatechangeisuncertain;Knorr(1961)firstsuggested
thatthisspecieswillnotnestonintermittentstreamsandthatevenindroughtyearswherethe
streamwasreducedtoatrickle,birdsreturnedtotheirnestingsites(Knorr1961;Knorr1993).The
degreetowhichperennialstreamsthatfeedwaterfallswithnestingsitesbecomeintermittentdue
toclimatechangeseemstobetheprimaryfactorindetermininghowvulnerablenestingsitesmay
be.Levadetal.(2008)didfindthatincreasedstreamflowcontributedtoahigherprobabilitythata
waterfallwouldbeoccupied.
C2c)Dependenceonaspecificdisturbanceregimelikelytobeimpactedbyclimatechange.
Neutral.
C2d)Dependenceonsnow‐coveredhabitats.Neutral.
C3)Restrictiontouncommongeologicalfeaturesorderivatives.SomewhatIncrease.This
species'closeassociationwithwaterfallsfornestsites(LowtherandCollins2002)increasesits
vulnerability.
C4a)Dependenceonotherspeciestogeneratehabitat.Neutral.
C4b)Dietaryversatility.Neutral. Diet items are diverse, but primarily limited to flying insects
(Lowther and Collins 2002).
C4c)Pollinatorversatility(Plantsonly,notapplicable).
ClimateChangeVulnerabilityAssessmentforColoradoBLM205
C4d)Dependenceonotherspeciesforpropaguledispersal.Neutral.
C4e)Formspartofaninterspecificinteractionnotcoveredby4a‐d.Unknown.
C5a)Measuredgeneticvariation.Unknown.MoreinformationisneededonBlackSwiftgenetics.
C5b)Occurrenceofbottlenecksinrecentevolutionaryhistory.Unknown.
C6)Phenologicalresponsetochangingseasonaltemperatureandprecipitationdynamics.
Unknown.
D1)Responsetorecentclimatechange.Unknown.
D2)Modeledfuturechangeinpopulationorrangesize.Unknown.
D3)Overlapofmodeledfuturerangewithcurrentrange.Unknown.
D4)Protectedareas.Unknown.
Literature Cited
ColoradoBirdAtlasPartnership,RadeauxandColoradoDivisionofWildlife.1998.ColoradoBreedingBirdAtlas.Denver,
Colorado:ColoradoBirdAtlasPartnership.636pg.
Knorr,O.A.1961.ThegeographicalandecologicaldistributionoftheBlackSwiftinColorado.WilsonBulletin73:155‐170.
Knorr,O.A.1993.BreedingoftheBlackSwiftintheGreatBasin.WesternBirds24:197‐198.
Levad,R.G.,K.M.Potter,C.W.Schultz,C.Gunn,andJ.G.Doerr.2008.Distribution,abundance,andnest‐sitecharacteristics
ofBlackSwiftsintheSouthernRockyMountainsofColoradoandNewMexico.TheWilsonJournalofOrnithology
120:331‐338.
Lowther,P.E.,andC.T.Collins.2002.BlackSwift(Cypseloidesniger).InTheBirdsofNorthAmerica,No.676(A.Pooleand
F.Gill,eds.).TheBirdsofNorthAmerica,Inc.,Philadelphia,PA.
206ColoradoNaturalHeritageProgram©2015
Brewer’s Sparrow
Spizellabreweri
G5/S4B
Family:Emberizidae
Climate Vulnerability Rank: Not Vulnerable/Presumed Stable
ThisColoradostate‐widerankisbasedonthefollowingfactors:1)potentialincreasehabitat
degradationdueoilandgasdevelopmentinBrewer’ssparrowhabitat;2)relianceonsagebrush
habitats;and3)positivecorrelationbetweenwinterprecipitationandclutchsize.TheBrewer’s
Sparrowmaybelessvulnerablethanotherbirdspeciesassessedinthisreportduetothelackof
barrierstomovement,highgeneticvariation,highdietaryversatility,andlongdistancemovement
patterns.
Distribution:Brewer’sSparrowsareoccurthroughoutmostofColorado,butarenotablyabsent
fromtheSanJuanBasin(ColoradoBirdAtlasPartnership1998;BoyleandReeder2005).Breeding
Brewer’sSparrowsaremostcommoninthemesasandfoothillsofwesternColorado,withthe
highestabundanceestimatesoccurringinthenorthwesterncornerofthestate(Lambeth1998).
Habitat:InColorado,Brewer’sSparrowsaremostfrequentlydocumentedinmountainbig
sagebrushhabitats(ColoradoBirdAtlasPartnership1998).Theyalsooccurinthefollowing
vegetationtypesasdefinedbytheColoradoBreedingBirdAtlas(1998):lowlandsagebrush,tall
desertshrub,shortgrassortallgrass/sandsage,montanegrassland,mountainshrub,pinyon‐juniper
woodland.Elevation:Commonlynestingbetween5,000and7,500ft(AndrewsandRighter1992).
EcologicalSystem:Sagebrushshrubland,Sandsage,DesertShrublands,Pinyon‐Juniper
CCVI Scoring
B1)Exposuretosealevelrise.Neutral.
ClimateChangeVulnerabilityAssessmentforColoradoBLM207
B2a)Distributionrelativetonaturalbarriers.Neutral.Brewer'sSparrowsarefoundonboththe
EastandWestSlopeofColorado,fromlowelevationareasontheplains,tohighelevationsitesnear
timberline(11,400feet)(HansleyandBeauvais2004).
B2b)Distributionrelativetoanthropogenicbarriers.Neutral.Thisspeciesoccupiesabroad
geographicandelevationrangeinCO.Noanthropogenicbarriershavebeenreportedforthe
species(HansleyandBeauvais2004).
B3)Impactoflandusechangesresultingfromhumanresponsestoclimatechange.
SomewhatIncrease.Brewer'sSparrowsareconsideredsagebrushobligates.NWColorado,
includingRioBlancoCounty,containslargeexpansesofsagebrushshrublands.Atotalof2,915
activenaturalgaswellsarecurrentlyoperatinginRioBlancoCounty(COGCC2015).Aprojected
1,845newwellswillbedrilledinRioBlancoCountyin2035tomeetenergydemandsinColorado
(BBC2008).Increasedenergydevelopmentinthisareawillresultinfurtherhabitatfragmentation
forBrewer'sSparrow.
C1)Dispersalandmovements.Decrease.Brewer'sSparrowsmigratelongdistancesacrossthe
WesternUS,winteringinTexas,California,andNevada,andtravelingnorthtoCanada,Wyoming,
Colorado,andtheGreatPlainstobreed(ColoradoBirdAtlasPartnership2008).
C2ai)Predictedsensitivitytotemperature:historicalthermalniche.Neutral.Consideringthe
meanseasonaltemperaturevariationforoccupiedcells,thespecieshasexperiencedaverage(57.1‐
77°F/31.8‐43.0°C)temperaturevariationinthepast50years.
C2aii)Predictedsensitivitytotemperature:physiologicalthermalniche.Neutral.Lessthan
10%ofsagebrushecosystemsinColoradoareprojectedtobeoutsideofitscurrentclimatic
envelope(SeeEcosystemSectionofreport).
C2bi)Predictedsensitivitytochangesinprecipitation,hydrology,ormoistureregime:
historicalhydrologicalniche.SomewhatDecrease.Consideringtherangeofmeanannual
precipitationacrossoccupiedcells,thespecieshasexperiencedgreaterthanaverage(>40
inches/1,016mm)precipitationvariationinthepast50years.
C2bii)Predictedsensitivitytochangesinprecipitation,hydrology,ormoistureregime:
physiologicalhydrologicalniche.Neutral.Thisspeciesdoesnotrelyonastronglyseasonal
hydrologicregime.
C2c)Dependenceonaspecificdisturbanceregimelikelytobeimpactedbyclimatechange.
Neutral.Thisspeciesdoesnotrelyonaspecificdisturbanceregimethatwillbeimpactedbyclimate
change.
C2d)Dependenceonsnow‐coveredhabitats.SomewhatIncrease.Clutchsizeappearstobe
positivelycorrelatedwithwinterprecipitation(PetersonandBest1986;Lack1966).
C3)Restrictiontouncommongeologicalfeaturesorderivatives.Neutral.
208ColoradoNaturalHeritageProgram©2015
C4a)Dependenceonotherspeciestogeneratehabitat.GreatlyIncrease.Thisspeciesismost
frequentlyassociatedwithmountainbigsagebrushhabitatsinColorado.
C4b)Dietaryversatility.Neutral.Brewer'sSparrowseatawidevarietyofinsects(Petersonand
Best1986).Duringmigration,Brewer'sSparrowsrelymainlyonseedsandseedheadsforfood,
withinsectscomprisingonly10%oftheirdiet(Short1984).
C4c)Pollinatorversatility(Plantsonly,notapplicable).
C4d)Dependenceonotherspeciesforpropaguledispersal.Neutral.
C4e)Formspartofaninterspecificinteractionnotcoveredby4a‐d.Unknown.
C5a)Measuredgeneticvariation.Neutral.Geneticvariationorinbreedingdepressionhasnot
beenidentifiedasaconcernforBrewer'sSparrow(HansleyandBeauvais2004).
C5b)Occurrenceofbottlenecksinrecentevolutionaryhistory.Unknown
C6)Phenologicalresponsetochangingseasonaltemperatureandprecipitationdynamics.
Unknown.
D1)Responsetorecentclimatechange.Unknown.
D2)Modeledfuturechangeinpopulationorrangesize.Unknown.
D3)Overlapofmodeledfuturerangewithcurrentrange.Unknown.
D4)Protectedareas.Unknown.
Literature Cited
Andrews,R.andR.Righter.1992.Coloradobirds:areferencetotheirdistributionandhabitat.Denver:DenverMuseumof
NaturalHistory.
BBCResearchandConsulting.2008.NorthwestColoradoSocioeconomicAnalysisandForecasts.Reportpreparedfor
AssociatedGovernmentsofNorthwestColorado.179pg.Availableonlineat
http://www.colorado.gov/cs/Satellite?blobcol=urldata&blobheadername1=ContentDisposition&blobheadername2=Cont
entType&blobheadervalue1=inline%3B+filename%3D%22Full+Report.pdf%22&blobheadervalue2=application%2Fpdf&
blobkey=id&blobtable=MungoBlobs&blobwhere=1251731958720&ssbinary=true.
Boyle,S.A.andD.R.Reeder.2005.Coloradosagebrush:aconservationassessmentandstrategy.GrandJunction:Colorado
DivisionofWildlife.
ColoradoBirdAtlasPartnership,RadeauxandColoradoDivisionofWildlife.1998.ColoradoBreedingBirdAtlas.Denver,
Colorado:ColoradoBirdAtlasPartnership.636pg.
ColoradoOilandGasCommission(COGCC).2015.WeeklyOilandGasStatisticsforFeb2,2015.AccessedonlineFeb21,
2015atwww.colorado.gov/cogcc.
ClimateChangeVulnerabilityAssessmentforColoradoBLM209
Hansley,P.L.andG.P.Beauvais.2004.SpeciesAssessmentforBrewer'sSparrow(Spizellabreweri)inWyoming.Prepared
fortheBLM.49pages.
Lack,D.1966.Populationstudiesofbirds.ClarendonPress,Oxford,UK.
Lambeth,R.1998.Brewer'ssparrow(Spizellabreweri).InColoradoBreedingBirdAtlas,editedbyH.E.Kingery.Denver:
ColoradoBirdAtlasPartnership&ColoradoDiv.ofWildlife.
Petersen,K.L.andL.B.Best.1986.DietsofnestlingSageSparrowsandBrewer’sSparrowsinanIdahosagebrush
community.JournalofFieldOrnithology57:283‐294.
Short,H.L.1984.HabitatSuitabilityIndexmodels:Brewer’sSparrow.USDIFishandWildlifeServiceBiologicalReport
FWS/OBS‐82/10.83.
210ColoradoNaturalHeritageProgram©2015
Burrowing Owl
Athenecuniculariahypugaea
G4/S4B
Family:Strigidae
Climate Vulnerability Rank: Moderately Vulnerable
ThisColoradostate‐widerankisbasedonthefollowingfactors:1)dependenceonprairiedogsand
othermammalstocreatesuitablenestinghabitat;2)lowlevelsofgeneticdiversity;3)lackof
protectiononprivatelands;4)predictedlossof77%ofcurrentbreedingrangeduetoclimate
change(AudubonSociety2015).
Distribution:Breedingrecordscovermuchofthestate,althoughitismorecommonontheplains
ofeasternColorado(AndrewsandRighter1992,ColoradoBirdAtlasPartnership1998).Habitat:
Thisspeciesisfoundindryopentreelessareasandisassociatedwithburrowingmammals.
Burrowsareusuallysurroundedbybaregroundandprovideprotectionfromweatherextremes
(Haugetal.1993).Althoughcapableofdiggingtheirownburrowswhereburrowingmammalsare
absent,burrowingowlsusuallyuseexistingburrows,particularlythoseofprairiedogs.
EcologicalSystem:ShortgrassPrairie
CCVI Scoring
B1)Exposuretosealevelrise.Neutral.
B2a)Distributionrelativetonaturalbarriers.Neutral.
B2b)Distributionrelativetoanthropogenicbarriers.Neutral.
B3)Impactoflandusechangesresultingfromhumanresponsestoclimatechange.
SomewhatIncrease.AccordingtoDepartmentofEnergywindresourcemaps,theeasternquarterof
©DonBaccus
ClimateChangeVulnerabilityAssessmentforColoradoBLM211
ColoradoneartheNewMexicoandNebraskabordershasexcellentwindresources(DOE2004).
Windturbinescancausedirectimpactstobirdsviacollisionsthatresultininjuryormortality
(Kunzetal.2007;Kuvleskyetal.2007),aswellasindirectimpactsviahabitatlossandbarriersto
movement(DrewittandLangston2006;Kuvleskyetal.2007;Pruettetal.2009;Kieseckeretal.
2011).ResultsfromastudyatawindfarminCaliforniasuggestthatwindturbinesannuallykill
betweenone‐fifthandnearlytwicethenumberofestimatedowlsintheavailablehabitatarea
(Smallwoodetal.2010).
C1)Dispersalandmovements.Decrease.TheBurrowingOwliscapableoflongdistance
migration,andBurrowingOwlsbandedinAlberta,CanadahavebeenrecoveredinMexico(USFWS
2003).
C2ai)Predictedsensitivitytotemperature:historicalthermalniche.Neutral.Consideringthe
meanseasonaltemperaturevariationforoccupiedcells,thespecieshasexperiencedaverage(57.1‐
77°F/31.8‐43.0°C)temperaturevariationinthepast50years.
C2aii)Predictedsensitivitytotemperature:physiologicalthermalniche.Neutral.Thisspecies
isassociatedwithshortgrassprairieinColoradoandisnotlimitedtocoolorcoldhabitats
(ColoradoBirdAtlasPartnership1998).
C2bi)Predictedsensitivitytochangesinprecipitation,hydrology,ormoistureregime:
historicalhydrologicalniche.SomewhatDecrease.Consideringtherangeofmeanannual
precipitationacrossoccupiedcells,thespecieshasexperiencedgreaterthanaverage(>40
inches/1,016mm)precipitationvariationinthepast50years.
C2bii)Predictedsensitivitytochangesinprecipitation,hydrology,ormoistureregime:
physiologicalhydrologicalniche.Neutral.StudiesonthePawneeNationalGrasslandshowed
decreasedsurvivalinowletsduringwetsummers(Conrey2010).Preypopulationsmayrespond
positivelytoincreasedrainfall,butBurrowingOwlstypicallydonothuntinwetweather(Conrey
2010).
C2c)Dependenceonaspecificdisturbanceregimelikelytobeimpactedbyclimatechange.
Neutral.
C2d)Dependenceonsnow‐coveredhabitats.Neutral.
C3)Restrictiontouncommongeologicalfeaturesorderivatives.Neutral.Sandysoilsmay
permiteasierdiggingforprairiedogs,badgers,andBurrowingOwlsthatcreateburrowsinthe
shortgrassprairie.
C4a)Dependenceonotherspeciestogeneratehabitat.SomewhatIncrease.BurrowingOwls
nestinburrowsthatarecreatedbyprairiedogsandothermammals(ColoradoBirdAtlas
Partnership1998).
212ColoradoNaturalHeritageProgram©2015
C4b)Dietaryversatility.Neutral.BurrowingOwlsonthePawneeGrasslandatebeetles,
grasshoppers,ants,rodents,andsongbirds;insectscomprised95%oftheirdietbynumberand
only11%bybiomass(Conrey2010).
C4c)Pollinatorversatility(Plantsonly,notapplicable).
C4d)Dependenceonotherspeciesforpropaguledispersal.Neutral.
C4e)Formspartofaninterspecificinteractionnotcoveredby4a‐d.Neutral.
C5a)Measuredgeneticvariation.Increase.Lowlevelsofgeneticvariationhavebeendocumented
inBurrowingOwls,basedonmicrosatellitedatafrompopulationsdistributedthroughoutNorth
America(Macias‐Duarteetal.2010).
C5b)Occurrenceofbottlenecksinrecentevolutionaryhistory.Unknown.
C6)Phenologicalresponsetochangingseasonaltemperatureandprecipitationdynamics.
Unknown.
D1)Responsetorecentclimatechange.Neutral.
D2)Modeledfuturechangeinpopulationorrangesize.Increase.AudubonSociety’sclimate
modelspredictthatby2080,BurrowingOwlscouldlose77%oftheircurrentbreedingrange
(AudubonSociety2015).
D3)Overlapofmodeledfuturerangewithcurrentrange.Unknown.
D4)Protectedareas.Increase.InColorado,mostareasontheeasternplainsinBurrowingOwl
habitatareonprivatelands.
Literature Cited
Andrews,R.A.,andR.Righter.1992.Coloradobirds.DenverMuseumofNaturalHistory.Denver,Co.Pp363
AudubonSociety.2015.ClimateModelsforBurrowingOwl.Onlineat
http://climate.audubon.org/birds/burowl/burrowing‐owl.AccessedFeb21,2015.
ColoradoBirdAtlasPartnership,RadeauxandColoradoDivisionofWildlife.1998.ColoradoBreedingBirdAtlas.Denver,
Colorado:ColoradoBirdAtlasPartnership.636pg.
Conrey,R.Y.2010.Breedingsuccess,preyuse,andmark–resightestimationofburrowingowlsnestingonblack‐tailed
prairiedogtowns:Plagueaffectsanon‐susceptibleraptor.Ph.D.dissertation,ColoradoStateUniversity,FortCollins,CO.
DepartmentofEnergy(DOE).2004.WINDExchange.ColoradoWindResourceMap.Availableonlineat
http://apps2.eere.energy.gov/wind/windexchange/wind_resource_maps.asp?stateab=co.AccessedFeb2,2015
Drewitt,A.L.andR.H.W.Langston.2006.AssessingtheImpactsofWindFarmsonBirds.Ibis148:29‐42.
Haug,E.A.,B.AMillsap,andM.S.Martell.1993.BurrowingOwl(Speotytocunicularia),inTheBirdsofNorthAmerica(A.
PooleandF.Gill,eds.),no.61.Acad.Nat.Sci.,Philadelphia
ClimateChangeVulnerabilityAssessmentforColoradoBLM213
Kiesecker,J.M.,J.S.Evans,J.Fargione,K.Doherty,K.R.Foresman,T.H.Kunz,D.Naugle,N.P.Nibbelink,andN.D.Nieumuth.
2011.Win‐winforwindandwildlife:avisiontofacilitatesustainabledevelopment.PlosONE6:e17566.
Kunz,T.H.,E.B.Arnett,B.M.Cooper,W.P.Erickson,R.P.Larkin,T.Mabee,M.L.Morrison,M.D.Strickland,andJ.M.
Szewczak.2007.Assessingimpactsofwind‐energydevelopmentonnocturnallyactivebirdsandbats:aguidance
document.JournalofWildlifeManagement71:2449–4486.Available:http://www.wind‐watch.org/documents/wp‐
content/uploads/wild‐71‐08‐45.pdf.
Kuvlesky,W.P.Jr.,L.A.Brennan,M.L.Morrison,K.K.Boydston,B.M.BallardandF.C.Bryant.2007.WindEnergy
DevelopmentandWildlifeConservation:ChallengesandOpportunities.JournalofWildlifeManagement71(8):2487‐
2498.
Macias‐Duarte,A.,C.J.Conway,A.Munguia‐Vega,andM.Culver.2010.NovelmicrosatellitelocifortheBurrowingOwl,
Athenecunicularia.ConservationGeneticsResources2:67‐69.
Pruett,C.L.,M.A.Patten,andD.H.Wolfe.2009.AvoidanceBehaviorbyPrairieGrouse:ImplicationsforDevelopmentof
WindEnergy.ConservationBiology23(5)1253‐1259.
Smallwood,K.S.,C.G.Thelander,M.L.Morrison,L.M.Rugge.2010.BurrowingOwlMortalityintheAltamontPassWind
ResourceArea.TheJournalofWildlifeManagement71(5):1513‐1524).
U.S.FishandWildlifeService.2003.StatusAssessmentandConservationPlanfortheWesternBurrowingOwlinthe
UnitedStates.BiologicalTechnicalPublicationR6001‐2003.120pg.
214ColoradoNaturalHeritageProgram©2015
Golden Eagle
Aquilachrysaetos
G5/S3S4B,S4N
Family:Accipitridae
Climate Vulnerability Rank: Moderately Vulnerable
ThisColoradostatewiderankisbasedon:theprojectedincreasesintemperaturefortheassessed
area,increasedwindenergydevelopmentandthegreaterrisktomortalityfromwindturbinesthan
otherraptors,limitedprecipitationvariationtheeaglehashistoricallyexperienced,limitednumber
ofpreyspeciestheeagledependsupon,andapredicteddecreaseinbreedingrange.Climate
projectionssuggestthatsummertemperaturesacrosstherangeoftheGoldenEagleintheassessed
areawillincrease6°Fbytheendofthecenturyunderaloweremissionsscenario,withincreasesof
morethan10°Fbytheendofthecenturyunderahigheremissionsscenario(Karletal.2009).
Distribution:InColorado,goldeneaglesbreedprimarilyinmontanehabitatsinthewestand
canyonhabitatsinthesoutheast.ThereissomelimitedbreedinginnortheastColorado.Inwinter,
goldeneaglesrangemorewidelyandoccurcommonlythroughoutColorado.Habitat:Golden
eaglesuseaverywiderangeofhabitats.Fornestingtheymostfrequentlyusecliffsbutwillalso
nestintrees.Becauseoftheirlargesizeandpredatorynature,theyrequirelargeareasofforaging
habitat.Forforagingtheyusehigh‐andmid‐elevationpineforest,piñon‐juniperwoodlands,
sagebrushandothershrubhabitats,grassland,andagriculturalhabitatsareallusedbyGolden
eagles.
CCVI Scoring
B1)Exposuretosealevelrise.Neutral.
ClimateChangeVulnerabilityAssessmentforColoradoBLM215
B2a)Distributionrelativetonaturalbarriers.Neutral.Significantnaturalbarriersdonotexist
forthisspecies.Thisraptorisavolantspeciesthatcantraversemountainrangesandlargebodies
ofwater.
B2b)Distributionrelativetoanthropogenicbarriers.Neutral.Significantanthropogenic
barriersdonotexistforthisspecies.Thisraptorisavolantspeciesthatcanflyoveroraround
potentialanthropogenicbarriers.
B3)Impactoflandusechangesresultingfromhumanresponsestoclimatechange.
Somewhatincrease.GoldenEaglesareatgreaterrisktomortalityfromwindturbinesthanother
raptors(USFWS2011).Windenergydevelopmentisexpectedtoincreasewithintherangeofthe
GoldenEagleinColorado(NRDC2014).
C1)Dispersalandmovements.Decrease.GoldenEaglesreadilydispersemorethan10kilometers
fromhatchingsitetobreedingareas(Kochertetal.2002)
C2ai)Predictedsensitivitytotemperature:historicalthermalniche.Neutral.Therange
occupiedbytheGoldeneagleintheassessedareahasexperiencedanaverage(51.7‐77°F/31.8‐
43.0°C)zonalmeanseasonaltemperatureoverthelast50years.
C2aii)Predictedsensitivitytotemperature:physiologicalthermalniche.Somewhatincrease.
InNorthAmerica,GoldenEagle'sbreedingsuccessappearstobecompromisedbythenumberof
extremelyhotdaysduringthebroodrearingperiod(Steenhofetal.1997).Climateprojections
suggestthatsummertemperaturesacrosstherangeoftheGoldenEagleintheassessedareawill
increase6°Fbytheendofthecenturyunderaloweremissionsscenario,withincreasesofmore
than10°Fbytheendofthecenturyunderahigheremissionsscenario(Karletal.2009)
C2bi)Predictedsensitivitytochangesinprecipitation,hydrology,ormoistureregime:
historicalhydrologicalniche.Somewhatincrease.WithintheassessedareatheGoldenEaglehas
experiencedslightlylowerthanaverage(20‐30inches/255‐508mm)precipitationvariationinthe
past50years.
C2bii)Predictedsensitivitytochangesinprecipitation,hydrology,ormoistureregime:
physiologicalhydrologicalniche.Neutral.GoldenEaglereproductivesuccessappearstobe
independentofanyparticularprecipitationregime(Steenhofetal.1997andCrandall2005).
C2c)Dependenceonaspecificdisturbanceregimelikelytobeimpactedbyclimatechange.
Neutral.TheGoldenEagleisnotdependentonanydisturbanceregimesuchasfireorfloodingand
aremostdependentuponsuitablepreypopulationsinforagingareas(Steenhofetal.1997and
Crandall2005).
C2d)Dependenceonsnow‐coveredhabitats.Neutral.TheGoldenEagleisnotdependenton
habitatswithice,snow,oronsnowpack.
216ColoradoNaturalHeritageProgram©2015
C3)Restrictiontouncommongeologicalfeaturesorderivatives.Neutral.TheGoldenEagleis
notdependentuponanyuncommongeologicalelements.However,theyoftennestoncliffs,butalso
willnestintreesandontheground,riverbanksandhumanstructures(Kochertetal.2002).
Climatechangeshouldnotimpacttheavailabilityofsuitablecliffsitesfornesting.
C4a)Dependenceonotherspeciestogeneratehabitat.Neutral.TheGoldenEagleisnot
dependentonanyotherspeciestocreatesuitablehabitatforitsexistence.
C4b)Dietaryversatility.Somewhatincrease.TheGoldenEagledependsuponafewsmall
mammalaspreyincludinghares(Lepusspp.)andrabbits(Sylvilagusspp.);alsogroundsquirrels
(Spermophilusspp.),prairiedogs(Cynomysspp.)andmarmots(Marmotaspp.)(Kochertetal.
2002).
C4d)Dependenceonotherspeciesforpropaguledispersal.Neutral.TheGoldenEagleisaself‐
disperser.
C4e)Formspartofaninterspecificinteractionnotcoveredby4a‐d.Neutral.Noother
interspecificinteractions,otherthanthosediscussedabove,areimportanttothepersistenceofthe
GoldenEagle.
C5a)Measuredgeneticvariation.Neutral.Thegeneticdiversityofthegoldeneaglehasbeen
reportedtobeaverage(Doyleetal.2014).
C5b)Occurrenceofbottlenecksinrecentevolutionaryhistory.Unknown.
C6)Phenologicalresponsetochangingseasonaltemperatureandprecipitationdynamics.
Unknown.
D1)Responsetorecentclimatechange.Unknown.
D2)Modeledfuturechangeinpopulationorrangesize.Increase.Thepredictedbreedingrange
oftheGoldenEagleintheassessedareaispredictedtodeclineby79percent(NationalAudubon
Society2013).
D3)Overlapofmodeledfuturerangewithcurrentrange.Unknown.
D4)Protectedareas.Unknown.
Literature Cited
Crandall,R.H.2005.IdentifyingenvironmentalfactorsinfluencingGoldenEaglepresenceandreproductivesuccess.
Master'sthesis,UniversityofMontana.
DoyleJM,KatznerTE,BloomPH,JiY,WijayawardenaBK,etal.(2014)TheGenomeSequenceofaWidespreadApex
Predator,theGoldenEagle(Aquilachrysaetos).PLoSONE9(4):e95599.doi:10.1371/journal.pone.0095599
ClimateChangeVulnerabilityAssessmentforColoradoBLM217
Karl,T.R.,J.M.Melillo,andT.C.Peterson,(eds.).2009.GlobalClimateChangeImpactsintheUnitedStates.Cambridge
UniversityPress.
Kochert,M.N.,K.Steenhof,CL.McintyreandE.H.Craig.2002.GoldenEagle(Aquilachrysaetos),TheBirdsofNorth
AmericaOnline(A.Poole,Ed.).Ithaca:CornellLabofOrnithology;RetrievedfromtheBirdsofNorthAmericaOnline:
http://bna.birds.cornell.edu/bna/species/684doi:10.2173/bna.684"
NationalAudubonSociety.2013.DevelopingaManagementModeloftheEffectsofFutureClimateChangeonSpecies:A
ToolfortheLandscapeConservationCooperatives.UnpublishedreportpreparedfortheU.S.FishandWildlifeService.
NaturalResourcesDefenseCouncil(NRDC).2014.RenewableenergyforAmerica.
http://www.nrdc.org/energy/renewables/energymap.asp
Steenhof,K.,M.N.KochertandT.L.McDonald.1997.InteractiveEffectsofPreyandWeatheronGoldenEagle
Reproduction.JournalofAnimalEcology,66:350‐362.
U.S.FishandWildlifeService(USFWS).2011.DraftEagleConservationPlanGuidance.

218ColoradoNaturalHeritageProgram©2015
Greater Sage‐grouse
Centrocercusurophasianus
G3G4/S4
Family:Phasianidae
Climate Vulnerability Rank: Highly Vulnerable
ThisColoradostate‐widerankofHighlyVulnerableisbasedonthefollowingfactors:1)lessthan
10%ofsagebrushecosystemsinCOareprojectedtobeoutsideofcurrentclimaticenvelope(see
Ecosystemschapter);2)outsideoftheirrelianceonsagebrushforcoverandfood,thisspecieshas
fewrestrictionstouncommongeologicfeatures,norelianceonintraspecificrelationships;3)
GreaterSage‐grouse(GrSG)arecapableofmovingseveralkilometers;4)GrSGhaveexperienced
averagetemperaturevariationinthepast50years;5)geneticvariationinColoradoishigherthan
otherpartsoftheGrSGrange.
Distribution:Greatersage‐grouseoccurintheWesternUnitedStatesandCanada.Coloradoison
thesoutheasternedgeofthecurrentGrSGrange(ColoradoGreaterSage‐grouseSteering
Committee[CGSGSC]2008).WithinColorado,theoccupiedrangeofGrSGisinthenorthwestcorner
ofthestateinthefollowingcounties:Eagle,Garfield,Grand,Jackson,Larimer,Mesa,Moffat,Rio
Blanco,Routt,andSummit.Habitat:TheGrSGaredependentonsagebrushyeararoundforfood
andcover.Femalesandbroodsmayselectriparianhabitatsinthesagebrushtypethatcontainhigh
coverofforbsandabundantmoisture(seeCGSGSC2008fordiscussionofseasonalhabitatuse
withinsagebrushshrublands).Elevation:7,900‐9,500feet.
EcologicalSystem:Sagebrushshrubland
CCVI Scoring
B1)Exposuretosealevelrise.Neutral.
ClimateChangeVulnerabilityAssessmentforColoradoBLM219
B2a)Distributionrelativetonaturalbarriers.SomewhatIncrease.Severalpopulationsonthe
easternedgeofoccupiedhabitatinCOareseparatedbytheParkRange.Thesehighalpineareas
andruggedpeaksmayactasanaturalbarrierformovement.
B2b)Distributionrelativetoanthropogenicbarriers.SomewhatIncrease.Thismountainrange
isapotentialnaturalbarrierforGrSG.RivervalleysandlargeagriculturalareasinAlberta,
Saskatchewan,Montana,andWyomingweresignificantbarrierstoGrSGmovement(Bushetal.
2011).TheeasternandsouthernedgesofGrSGrangeinColoradocontainirrigatedanddryland
agriculturalfieldsthatmayserveasbarrierstoGrSGmovement(USGSNationalGapAnalysis
Program2004).
B3)Impactoflandusechangesresultingfromhumanresponsestoclimatechange.
SomewhatIncrease.GrSGareconsideredsagebrushobligates.NWColorado,includingRioBlanco
County,containslargeexpansesofsagebrushshrublands.Atotalof2,915activenaturalgaswells
arecurrentlyoperatinginRioBlancoCounty(COGCC2015).Aprojected1,845newwellswillbe
drilledinRioBlancoCountyin2035tomeetenergydemandsinColorado(BBC2008).Increased
energydevelopmentinthisareawillresultinfurtherhabitatfragmentationforGrSG.Lessthanone
percentoffederallandsinColoradocontainwindenergydevelopmentright‐of‐wayswithin
PriorityAreasforGrSGConservationinColorado(LeBeauetal.2014).
C1)Dispersalandmovements.Decrease.Averagenest‐to‐wintermovementsinGrSGinWyoming
averaged14.4kminarecentstudy(Fedyetal.2012).
C2ai)Predictedsensitivitytotemperature:historicalthermalniche.Neutral.Consideringthe
meanseasonaltemperaturevariationforoccupiedcells,GrSGhasexperiencedaverage(57.1‐77°
F/31.8‐43.0°C)temperaturevariationinthepast50years.
C2aii)Predictedsensitivitytotemperature:physiologicalthermalniche.Neutral.Lessthan
10%ofsagebrushecosystemsinColoradoareprojectedtobeoutsideofitscurrentclimatic
envelope(SeeEcosystemSectionofreport).
C2bi)Predictedsensitivitytochangesinprecipitation,hydrology,ormoistureregime:
historicalhydrologicalniche.SomewhatDecrease.Consideringtherangeofmeanannual
precipitationacrossoccupiedcells,GrSGhasexperiencedgreaterthanaverage(>40inches/1,016
mm)precipitationvariationinthepast50years.
C2bii)Predictedsensitivitytochangesinprecipitation,hydrology,ormoistureregime:
physiologicalhydrologicalniche.GreatlyIncrease.Highqualitybrood‐rearinghabitatsareoften
locatedinmesicareaslikestreambedsandwetmeadows(Connellyetal.2000).
C2c)Dependenceonaspecificdisturbanceregimelikelytobeimpactedbyclimatechange.
SomewhatIncrease.FireisconsideredoneofthetopthreatstoGrSG.Althoughhistoricallynatural
fireswereoftenlargeandsevere,theyweretypicallyinfrequentinGrSGhabitat(Brooksetal.
2015).However,duringrecentdecades,fireprobabilityandoccurrencehasincreasedacrossGrSG
220ColoradoNaturalHeritageProgram©2015
habitat,hinderingtherecoveryofsagebrush,andposingathreattoGrSGhabitat(Brooksetal
2015.)
C2d)Dependenceonsnow‐coveredhabitats.Neutral.Thisspeciesmakessnowroostsand
burrows(Backetal.1987),butisnotcompletelydependentonsnowcoverforsurvival.
C3)Restrictiontouncommongeologicalfeaturesorderivatives.SomewhatDecrease.This
speciesisnotrestrictedtouncommongeologicfeatures.
C4a)Dependenceonotherspeciestogeneratehabitat.GreatlyIncrease.TheGrSGrelyon
sagebrushyear‐roundforfoodandcover.
C4b)Dietaryversatility.SomewhatIncrease.Duringthespringandsummer,GrSGconsume
insectsandforbs;theirfallandwinterdietiscomprisedentirelyofsagebrush(CGSGSC2008).
C4c)Pollinatorversatility(Plantsonly,notapplicable).
C4d)Dependenceonotherspeciesforpropaguledispersal.Neutral.
C4e)Formspartofaninterspecificinteractionnotcoveredby4a‐d.Unknown.
C5a)Measuredgeneticvariation.Neutral.NorthPark,MiddlePark,andEaglepopulationsin
high‐elevationvalleyinColoradoaregeneticallydistinctfrompopulationsintheWyomingBasin
thataremorewide‐spread(Oyler‐McCanceetal.2005).NopopulationsinColoradohavebeen
identifiedashavinganextremelylownumberofhaplotypes,ascomparedtothoseintheColumbia
Basin(Oyler‐Mccanceetal.2005).
C5b)Occurrenceofbottlenecksinrecentevolutionaryhistory.Neutral.Geneticstestingacross
therangeofGrSGdidnotrevealanypopulationbottlenecksinColoradopopulations(Oyler‐
Mccanceetal.2005).C6)Phenologicalresponsetochangingseasonaltemperatureand
precipitationdynamics.Unknown.
D1)Responsetorecentclimatechange.Unknown.
D2)Modeledfuturechangeinpopulationorrangesize.Unknown.
D3)Overlapofmodeledfuturerangewithcurrentrange.Unknown.
D4)Protectedareas.Unknown.
Literature Cited
Back,G.N.,M.R.Barrington,andJ.K.McAdoo.1987.SageGrouseuseofsnowburrowsinnortheasternNevada.Wilson
Bulletin99:488‐490.
BBCResearchandConsulting.2008.NorthwestColoradoSocioeconomicAnalysisandForecasts.Reportpreparedfor
AssociatedGovernmentsofNorthwestColorado.179pg.Availableonlineat
http://www.colorado.gov/cs/Satellite?blobcol=urldata&blobheadername1=ContentDisposition&blobheadername2=Cont
ClimateChangeVulnerabilityAssessmentforColoradoBLM221
entType&blobheadervalue1=inline%3B+filename%3D%22Full+Report.pdf%22&blobheadervalue2=application%2Fpdf&
blobkey=id&blobtable=MungoBlobs&blobwhere=1251731958720&ssbinary=true.
Brooks,M.L.,J.R.Matchett,D.J.Shinneman,andP.S.Coates.2015.Firepatternsintherangeofgreatersage‐grouse,1984–
2013‐Implicationsforconservationandmanagement:U.S.GeologicalSurveyOpen‐FileReport2015‐1167,66p.
Bush,K.L.,C.K.Dyte,B.J.Moynahan,C.L.Aldridge,H.S.Sauls,A.M.Battazzo,B.L.Walker,K.E.Doherty,J.Tack,J.Carlson,D.
Eslinger,J.Nicholson,M.S.Boyce,D.E.Naugle,C.A.Paszkowski,andD.W.Coltman.2011.Populationstructureandgenetic
diversityofgreatersage‐grouse(Centrocercusurophasianus)infragmentedlandscapesatthenorthernedgeoftheir
range.ConservationGenetics12:527‐542
ColoradoGreaterSage‐grouseSteeringCommittee[CGSGSC].2008.Coloradogreatersage‐grouseconservationplan.
ColoradoDivisionofWildlife,Denver,Colorado,USA.
ColoradoOilandGasCommission(COGCC).2015.WeeklyOilandGasStatisticsforFeb2,2015.AccessedonlineFeb21,
2015atwww.colorado.gov/cogcc.
Connelly,J.W.,M.A.Schroeder,A.R.Sands,andC.E.Braun.2000.Guidelinestomanagesagegrousepopulationsandtheir
habitats.WildlifeSocietyBulletin28:967‐985.
Fedy,B.C.,C.L.Aldridge,K.E.Doherty,M.O’Donnell,J.L.Beck,B.Bedrosian,M.J.Holloran,G.D.Johnson,N.W.Kaczor,C.P.
Kirol,C.A.Mandich,D.Marshall,G.McKee,C.Olson,C.C.Swanson,andB.Walker.2012.Interseasonalmovementsof
greatersage‐grouse,migratorybehaviour,andanassessmentofthecoreregionsconceptinWyoming.JournalofWildlife
Management76(5):1062‐1071.
LeBeau,C.,J.Fruhwirth,J.R.Boehrs.2014.AnalysisoftheOverlapbetweenPriorityGreaterSage‐GrouseHabitatsand
ExistingandPotentialEnergyDevelopmentAcrosstheWest.FinalReportforWesternValuesProject.Preparedby
WesternEcoSystemsTechnology,Inc.36pg.Onlineat:http://westernvaluesproject.org/wp‐
content/uploads/2014/10/Greater‐Sage‐Grouse‐Priority‐Habitats‐and‐Energy‐Development.pdf.
Oyler‐McCance,S.J.,S.E.Taylor,andT.W.Quinn.2005.Amultilocusgeneticsurveyofgreatersage‐grouseacrosstheir
range.MolecularEcology14:1293‐1310.
USGSNationalGapAnalysisProgram.2004.ProvisionalDigitalLandCoverMapfortheSouthwesternUnitedStates.
Version1.0.RS/GISLaboratory,CollegeofNaturalResources,UtahStateUniversity.

222ColoradoNaturalHeritageProgram©2015
Gunnison Sage‐grouse
Centrocercusminimus
G1/S1
ListedThreatened
Family:Phasianidae
Climate Vulnerability Rank: Highly Vulnerable
ThisColoradostate‐widerankisbasedonthefollowingfactors:1)barrierstomovement;2)
potentialdecreaseingrowthofmountainbigsagebrushduetoclimatechange;3)relianceonmesic
habitattypesforbrood‐rearinghabitat;4)lackofgeneticdiversity;5)potentialincreaseinfire
frequencyinsagebrushhabitatsduetoprojectedtemperatureincreases.
Distribution:LimitedtosouthwestColoradoandsoutheastUtah.InColorado,Gunnison‐sage‐
grouseoccurinthefollowingcounties:Delta,Dolores,Gunnison,Hinsdale,Mesa,Montrose,San
Miguel,andSaguache(USFWS2014).Habitat:Gunnisonsage‐grouserelyonlargeexpansesof
sagebrushhabitatforfoodandcover;mesicareasalongripariancorridors,aswellaswetmeadows
providebrood‐rearinghabitat(USFWS2014).
EcologicalSystem:Sagebrushshrubland
CCVI Scoring
B1)Exposuretosealevelrise.Neutral.
B2a)Distributionrelativetonaturalbarriers.SomewhatIncrease.Gunnisonsage‐grouserely
onlarge,continuous,unfragmentedlandscapesforsurvival(GSGRSC2005).Theglobaldistribution
ofGunnisonsage‐grouseislimitedtosevenpopulations,sixofwhicharelocatedinColorado.The
remainingpopulationstraddlestheUtah/Coloradoborder.Gunnisonsage‐grouseoccurinareas
ClimateChangeVulnerabilityAssessmentforColoradoBLM223
withelevationsrangingfrom2,300to2,900m(7,500to9,5000ft)ofelevation.Areasbetween
manyoftheColoradopopulationsdonotcontainsuitablehabitatandhaveelevationsmuchhigher
thanthedocumentedrangepreferredbythespecies.TheGunnisonRiverandtheBlackCanyon
mayalsoposeanaturalbarriertomovement.
B2b)Distributionrelativetoanthropogenicbarriers.Increase/SomewhatIncrease.Asnoted
aboveinB2a,Gunnisonsage‐grouserelyonlarge,continuous,unfragmentedlandscapesfor
survival(GSGRSC2005).Humanpopulationsandassociateddevelopmentareprojectedtoincrease
nearmostGunnisonsage‐grousepopulations(USFWS2014).Habitatdeclinefromdisturbanceand
fragmentationcausedbyroadsandpowerlinesisacurrentandfuturethreattothesurvivalof
Gunnisonsage‐grouseinColorado(USFWS2014).
B3)Impactoflandusechangesresultingfromhumanresponsestoclimatechange.Neutral.
GeothermaldevelopmentpotentialishighintheGunnisonBasin,andifdevelopmentincreasedin
theBasin,itcouldaffectthelong‐termviabilityofGunnisonsage‐grousewithintheBasin(USFWS
2014).Noexisting,pending,orauthorizedwindenergysitesarewithintheColoradoportionof
occupiedGunnisonsage‐grousehabitat(USFWS2014).Noinformationregardingsolarenergy
developmentwasincludedinthefinalruleissuedbyUSFWSin2014,soitislikelynotathreatin
occupiedGunnisonsage‐grousehabitat.
C1)Dispersalandmovements.SomewhatDecrease.Gunnisonsage‐grousearegenerally
considerednonmigratory,butsomeseasonalmovementshavebeendocumented.IntheGunnison
Basin,individualsgenerallymovelessthan10km(GSGRSC2005),butmovementsasgreatas56
kmhavealsobeenreportedintheBasin(Phillips2013).
C2ai)Predictedsensitivitytotemperature:historicalthermalniche.Neutral.Consideringthe
meanseasonaltemperaturevariationforoccupiedcells,thespecieshasexperiencedaverage(57.1‐
77°F/31.8‐43.0°C)temperaturevariationinthepast50years.
C2aii)Predictedsensitivitytotemperature:physiologicalthermalniche.SomewhatIncrease.
PredictingtemperaturesinoccupiedhabitatforGunnisonsage‐grouseischallenging.Inone
scenario,averagesummertemperaturesarepredictedtoincreaseinwesternColoradoby2.8˚Cby
2050(UCAR2009),andaveragewintertemperaturescouldincreaseby2.2˚Cby2050(UCAR
2009).Overtime,increasedtemperaturescouldreducegrowthofmountainbigsagebrush,
resultinginareductionofsuitablehabitatforGunnisonsage‐grouse(USFWS2014).
C2bi)Predictedsensitivitytochangesinprecipitation,hydrology,ormoistureregime:
historicalhydrologicalniche.Neutral.Consideringtherangeofmeanannualprecipitationacross
occupiedcells,thespecieshasexperiencedaverage(21‐40inches/509‐1,016mm)precipitation
variationinthepast50years.
C2bii)Predictedsensitivitytochangesinprecipitation,hydrology,ormoistureregime:
physiologicalhydrologicalniche.GreatlyIncrease.Highqualitybrood‐rearinghabitatincludes
mesicmeadows,springs,seeps,andlowvegetationriparianareas,alldependentonadequate
224ColoradoNaturalHeritageProgram©2015
moisture(GSGRSC2005;USFWS2014).Thesehabitatstypesarehighlyvulnerabletoclimate
change.
C2c)Dependenceonaspecificdisturbanceregimelikelytobeimpactedbyclimatechange.
SomewhatIncrease.Inpreviousreports(TNCetal.2011),firehasbeencitedasanaturally
occurringeventthatbenefitsGunnisonsage‐grousebycreatingapatchworkoflowerandhigher
densitysagebrush,andthatclimatechangeislikelytoalterfireregimestherebyreducinghigh‐
qualityhabitatforthespecies.MorerecentreportsindicatethattheimpactsoffireonGunnison
sage‐grousehabitatarenotwellunderstood.However,itisgenerallyacceptedthatfirecancause
anincreaseinweedyplantspeciessuchascheatgrass,andcankillmountainbigsagebrush,
resultingindirectlossofhabitatduetoreducedcoverandforage(CallandMaser1985;USFWS
2014).FireisnotconsideredacurrentthreattoGunnisonsage‐grouse,butbestavailable
informationonclimatechangeindicatesthatfirefrequencyislikelyafuturethreattothespeciesif
firefrequencyincreasesaspredictedbyclimatechangemodels(Lukasetal.2014;USFWS2014).
C2d)Dependenceonsnow‐coveredhabitats.Neutral.Thisspeciesisnotdirectlydependenton
snoworiceforsurvival.
C3)Restrictiontouncommongeologicalfeaturesorderivatives.Neutral.
C4a)Dependenceonotherspeciestogeneratehabitat.GreatlyIncrease.Thisspeciesrelieson
sage‐brushasacriticalcomponentoftheirdiet,aswellasforcoverthroughallseasons(GSGRSC
2005).
C4b)Dietaryversatility.Increase.Gunnison’sSage‐grouserelyonsage‐brush(Artemisiaspp.)asa
criticalcomponentoftheirdietthroughoutallseasons;theyalsofeedonalargenumberofgrasses,
forbs,buds,andinsectswhenavailable(GSGRSC2005).Theyalsodependonherbsandforbsinthe
summeralongwiththeinsectsthatusethesamehabitat(importantforchickgrowth);factorsthat
couldbeimpactedbyclimatechangetothedegreethatitincludesdroughtsandhotspells(TNCet
al.2011).
C4c)Pollinatorversatility(Plantsonly,notapplicable).
C4d)Dependenceonotherspeciesforpropaguledispersal.GreatlyIncrease.Thisspeciesrelies
onsage‐brushasacriticalcomponentoftheirdiet,aswellasforcoverthroughallseasons(GSGRSC
2005).
C4e)Formspartofaninterspecificinteractionnotcoveredby4a‐d.Unknown.
C5a)Measuredgeneticvariation.Increase/SomewhatIncrease.GeneticdiversityinGunnison
sage‐grousehasbeeninvestigatedusingmitochondrialDNAandnuclearmicrosatellitedata(Oyler‐
McCanceetal.2005).Resultsindicatelowlevelsofdiversity,especiallyincomparisontodiversity
foundingreatersage‐grouse(Oyler‐McCanceetal.2005).
C5b)Occurrenceofbottlenecksinrecentevolutionaryhistory.Unknown.
ClimateChangeVulnerabilityAssessmentforColoradoBLM225
C6)Phenologicalresponsetochangingseasonaltemperatureandprecipitationdynamics.
Unknown.
D1)Responsetorecentclimatechange.Unknown.
D2)Modeledfuturechangeinpopulationorrangesize.Unknown.
D3)Overlapofmodeledfuturerangewithcurrentrange.Unknown.
D4)Protectedareas.Neutral.AcrosstheentirerangeofoccupiedhabitatforGunnisonsage‐
grouse,54percentoccursonFederallands,43percentonprivatelands,and3percentonstate
lands(USFWS2014).
Literature Cited
Call,M.W.andC.Maser1985.Call,M.W.andC.Maser.1985.Wildlifehabitatsinmanagedrangelands‐‐thegreatbasinof
southeasternOregon:Sagegrouse.Gen.Tech.Rep.PNW‐GTR‐187.Portland,OR:U.S.DepartmentofAgriculture,Forest
Service,PacificNorthwestResearchStation.
GunnisonSage‐grouseRangewideSteeringCommittee(GSGRSC).2005.Gunnisonsage‐grouserangewideconservation
plan.ColoradoDivisionofWildlife,Denver,Colorado.USA.
Lukas,J.,J.Barsugli,N.Doesken,I.Rangwala,andK.Wolter.2014.ClimateChangeinColorado:ASynthesistoSupport
WaterResourcesManagementandAdaptation.AReportfortheColoradoWaterConservationBoard.WesternWater
Assessment.
Oyler‐McCance,S.J.,J.St.John,S.E.Taylor,A.D.Apa,andT.W.Quinn.2005.PopulationgeneticsofGunnisonSage‐Grouse:
ImplicationsforManagement.JournalofWildlifeManagement69(2):630‐637.
Phillips,M.2013.PreliminarydataonGunnisonsage‐grousemovement,citedinUSFWS2014(seebelow).ColoradoParks
andWildlife.
TheNatureConservancy(TNC).2011.Gunnisonbasin:climatevulnerabilityassessmentreviewworkshop,Gunnison
climateworkinggroup,May12‐13,2011.130pp.
UniversityCorporationforAtmosphericResearch(UCAR).2009.RCPMdataandanalysisprovidedbytheInstituteforthe
StudyofSocietyandEnvironment(ISSE)attheNationalCenterforAtmosphericResearch(NCAR),basedonmodeldata
fromtheWorldClimateResearchProgramme'sCoupledModelIntercomparisonProjectphase3(WCRPCMIP3)multi‐
modeldataset.[http://rcpm.ucar.edu].
U.S.FishandWildlifeService(USFWS).2014.FinalRule,EndangeredandThreatenedWildlifeandPlants;Threatened
StatusforGunnisonSage‐Grouse.FederalRegisterVol79,No.224,Nov.20,2014.DepartmentoftheInterior.

226ColoradoNaturalHeritageProgram©2015
Long‐Billed Curlew
Numeniusamericanus
G5/S2B
Family:Scolopacidae
Climate Vulnerability Rank: Highly Vulnerable
ThisColoradostate‐widerankisbasedonthefollowingfactors:1)potentialincreaseinwind
energydevelopmentinLong‐BilledCurlewbreedinghabitatand2)relianceonwetlands,pondsand
playasthatmaybevulnerabletodryingunderprojectedincreasesintemperatureduetoclimate
change.
Distribution:InColorado,Long‐BilledCurlewbreedontheeasternplainswithpopulations
concentratedinthesoutheastcornerofthestate(ColoradoPartnersinFlight2000;ColoradoBird
AtlasPartnership1998).Habitat:InColorado,Long‐BilledCurlewsbreedinshortgrassandmixed‐
grassprairiehabitats,usuallyincloseproximitytowater(ColoradoBirdAtlasPartnership1998).
Elevation:Noinformationonspecificelevationrangesisavailable,butduetotheirpresenceonthe
easternplains,itislikelythattheLong‐BilledCurlewismostcommonlyfoundbetween4,000and
7,000ft.
EcologicalSystem:ShortgrassPrairie,Mixed‐GrassPrairie
CCVI Scoring
B1)Exposuretosealevelrise.Neutral.
B2a)Distributionrelativetonaturalbarriers.SomewhatIncrease.TheRockyMountainsmay
actasabarriertomigration(Pageetal.2014).
B2b)Distributionrelativetoanthropogenicbarriers.SomewhatIncrease.Largetractsof
Colorado’sshortgrassprairiehavebeenconvertedtocropland.Long‐BilledCurlewusecropland
ClimateChangeVulnerabilityAssessmentforColoradoBLM227
lessthanexpectedbasedonavailability(Dechantetal.1999).Whilethisspeciesishighlymobile
andcapableofflyingovertheseareas,theremaybeenergeticcostsassociatedwithcrossingthese
croplandsinordertoreachmoresuitablehabitatinshortgrassprairie.
B3)Impactoflandusechangesresultingfromhumanresponsestoclimatechange.
SomewhatIncrease.Long‐BilledCurlewnestprimarilyineasternColoradoinshortgrassprairies,
withasmallcontingentinMesaCountyontheWesternSlope(ColoradoBirdAtlasPartnership
1998).AccordingtoDepartmentofEnergywindresourcemaps,theeasternquarterofColorado
neartheNewMexicoandNebraskabordershasexcellentwindresources(DOE2004).Wind
turbinescancausedirectimpactstobirdsviacollisionsthatresultininjuryormortality(Kunzetal.
2007;Kuvleskyetal.2007),aswellasindirectimpactsviahabitatlossandbarrierstomovement
(DrewittandLangston2006;Kuvleskyetal.2007;Pruettetal.2009;Kieseckeretal.2011).
C1)Dispersalandmovements.Decrease.Long‐BilledCurlewbreedinColoradoandundertake
long,seasonalmigrations.
C2ai)Predictedsensitivitytotemperature:historicalthermalniche.Neutral.Consideringthe
meanseasonaltemperaturevariationforoccupiedcells,thespecieshasexperiencedaverage(57.1‐
77°F/31.8‐43.0°C)temperaturevariationinthepast50years.
C2aii)Predictedsensitivitytotemperature:physiologicalthermalniche.Neutral.Thisspecies
isassociatedwithshortgrassprairieinColoradoandisnotlimitedtocoolorcoldhabitats
(ColoradoBirdAtlasPartnership1998).
C2bi)Predictedsensitivitytochangesinprecipitation,hydrology,ormoistureregime:
historicalhydrologicalniche.Neutral.Consideringtherangeofmeanannualprecipitationacross
occupiedcells,thespecieshasexperiencedaverage(21‐40inches/509‐1,016mm)precipitation
variationinthepast50years.
C2bii)Predictedsensitivitytochangesinprecipitation,hydrology,ormoistureregime:
physiologicalhydrologicalniche.Increase.Thisspeciesreliesonbothdryandwetareasinthe
shortgrassprairie.GrassyfloodplainsalongcreeksinColoradoprovidenestinghabitatforLong‐
BilledCurlewinColorado;wetmeadowsareoftenusedasforagingareas(Davis1949;Johnsgard
1979and1980).
C2c)Dependenceonaspecificdisturbanceregimelikelytobeimpactedbyclimatechange.
SomewhatIncrease.Long‐BilledCurlewrelyonponds,playas,andlakesforfeeding,bathingand
drinking(ColoradoBirdAtlasPartnership1998).Ontheshortgrassprairie,manyofthesearetied
toseasonalprecipitationsuchasspringandsummerrainevents.
C2d)Dependenceonsnow‐coveredhabitats.Neutral.
C3)Restrictiontouncommongeologicalfeaturesorderivatives.SomewhatIncrease.Long‐
BilledCurlewusewetmeadowsandplayasineasternColorado,whichcanbeunusualfeaturesin
manycountieswhereshortgrassprairiehasbeenconvertedtocropland.
228ColoradoNaturalHeritageProgram©2015
C4a)Dependenceonotherspeciestogeneratehabitat.Neutral.
C4b)Dietaryversatility.Neutral.TheLong‐BilledCurlewispredominantlycarnivorous,and
consumessmallinvertebrates(grasshoppers,beetles,earthworms,spiders)aswellassomewild
fruits(DuggerandDugger2002;seeallauthorsinDark‐SmileyandKeinath2004).Largerprey
itemsincludetoadsandsnails,whichareconsumedduringmigration(RedmondandJenni1986).
C4c)Pollinatorversatility(Plantsonly,notapplicable).
C4d)Dependenceonotherspeciesforpropaguledispersal.Neutral.
C4e)Formspartofaninterspecificinteractionnotcoveredby4a‐d.Unknown.
C5a)Measuredgeneticvariation.Unknown.MoreinformationisneededonLong‐BilledCurlew
genetics.
C5b)Occurrenceofbottlenecksinrecentevolutionaryhistory.Unknown.
C6)Phenologicalresponsetochangingseasonaltemperatureandprecipitationdynamics.
Unknown.
D1)Responsetorecentclimatechange.Unknown.
D2)Modeledfuturechangeinpopulationorrangesize.Unknown.
D3)Overlapofmodeledfuturerangewithcurrentrange.Unknown.
D4)Protectedareas.Unknown.
Literature Cited
ColoradoBirdAtlasPartnership,RadeauxandColoradoDivisionofWildlife.1998.ColoradoBreedingBirdAtlas.Denver,
Colorado:ColoradoBirdAtlasPartnership.636pg.
ColoradoPartnersInFlight[CoPIF].2000.ColoradoLandbirdConservationPlan.Available:www.rmbo.org/pif/bcp/
Dark‐Smiley,D.N.andD.A.Keinath.2004.SpeciesAssessmentforLong‐BilledCurlew(Numeniusamericanus)inWyoming.
PreparedfortheBureauofLandManagement,Cheyenne,Wyoming.WyomingNaturalDiversityDatabaseReport,60
pages.
Davis,W.B.1949.Long‐billedCurlewbreedinginColorado.Auk66:202.
Dechant,J.A.,M.L.Sondreal,D.H.Johnson,L.D.Igl,C.M.Goldade,P.A.Rabie,andB.R.Euliss.1999(revised2003).Effectsof
managementpracticesongrasslandbirds:Long‐billedCurlew.NorthernPrairieWildlifeResearchCenter,Jamestown,ND.
19pages.
DepartmentofEnergy(DOE).2004.WINDExchange.ColoradoWindResourceMap.Availableonlineat
http://apps2.eere.energy.gov/wind/windexchange/wind_resource_maps.asp?stateab=co.AccessedFeb2,2015.
Drewitt,A.L.andR.H.W.Langston.2006.AssessingtheImpactsofWindFarmsonBirds.Ibis148:29‐42.
ClimateChangeVulnerabilityAssessmentforColoradoBLM229
Dugger.B.D.,andK.M.Dugger.2002.Long‐billedCurlew(Numeniusamericanus).InTheBirdsofNorthAmerica,No.628
(A.PooleandF.Gill,eds.).TheBirdsofNorthAmerica,Inc.,Philadelphia,PA.
Johnsgard,P.A.1979.BirdsoftheGreatPlains.UniversityofNebraskaPress,Lincoln,Nebraska.539pages.
Johnsgard,P.A.1980.ApreliminarylistofthebirdsofNebraskaandadjacentPlainsstates.UniversityofNebraska,
Lincoln,Nebraska.156pages.
Kiesecker,J.M.,J.S.Evans,J.Fargione,K.Doherty,K.R.Foresman,T.H.Kunz,D.Naugle,N..Nibbelink,andN.D.Nieumuth.
2011.Win‐winforwindandwildlife:avisiontofacilitatesustainabledevelopment.PlosONE6:e17566.
Kunz,T.H.,E.B.Arnett,B.M.Cooper,W.P.Erickson,R..Larkin,T.Mabee,M.L.Morrison,M.D.Strickland,andJ.M.Szewczak.
2007a.Assessingimpactsofwind‐energydevelopmentonnocturnallyactivebirdsandbats:aguidancedocument.
JournalofWildlifeManagement71:2449–4486.Available:http://www.wind‐watch.org/documents/wp‐
content/uploads/wild‐71‐08‐45.pdf.
Kuvlesky,W.P.Jr.,L.A.Brennan,M.L.Morrison,K.K.Boydston,B.M.BallardandF.C.Bryant.2007.WindEnergy
DevelopmentandWildlifeConservation:ChallengesandOpportunities.JournalofWildlifeManagement71(8):2487‐
2498.
Page,G.W.,N.Warnock,T.L.Tibbitts,D.Jorgensen,C.A.Hartman,andL.E.Stenzel.2014.Annualmigratorypatternsof
Long‐BilledCurlewsintheAmericanWest.TheCondor116(1):50‐61.
Pruett,C.L.,M.A.Patten,andD.H.Wolfe.2009.AvoidanceBehaviorbyPrairieGrouse:ImplicationsforDevelopmentof
WindEnergy.ConservationBiology23(5)1253‐1259.
Redmond,R.L.,andD.A.Jenni.1986.PopulationecologyoftheLong‐billedCurlew(Numeniusamericanus)inwestern
Idaho.Auk103:755‐767.
230ColoradoNaturalHeritageProgram©2015
Mountain Plover
Charadriusmontanus
G3/S2B
Family:Charadriidae
Climate Vulnerability Rank: Not Vulnerable/Presumed Stable
ThisColoradostatewiderankisbasedon:thelackofnaturaloranthropogenicbarriersforthis
highlyvagilebird,theircapabilitytoengageinlongdistancedispersalandmovementsallowingthe
plovertotrackshiftingclimateenvelopes,theirpreferenceforburnedsites(AugustineandDerner
2012)coupledwithincreasedfirefrequencyprojectedduetoclimatechange,highratesofadult
survivalandnestsuccessratesduringperiodsofdroughtthatisprojectedtoincreasedueto
climatechange,andthehighgeneticvariabilityexhibitedwithinMountainploverpopulationsthat
shouldincreasetheirabilitytoadapttoclimatechange.Climatemodelsprojectincreasedwarming
anddroughtacrosstheassessedareawithannualaveragetemperaturesrisingby2.5°Fto5.5°Fby
2041‐2070andby5.5°Fto9.5°Fby2070‐2099withcontinuedgrowthinglobalemissions(A2
emissionsscenario),withthegreatestincreasesinthesummerbreedingseasonandduringfall
(Melilloetal.2014).
Distribution:InColorado,thegreatestnumbersofbreedingMountainPloversoccurinWeld
County(GraulandWebster1976).Thebreedingrangeofthisspecieshasundergoneadramatic
long‐termcontraction,bothinColorado(AndrewsandRighter1992)andthroughoutthewestern
GreatPlains(GraulandWebster1976).Habitat:BreedingMountainPloversoccupyopenhabitats
withlow‐growingvegetation,especiallyshortgrassprairiecharacterizedbythepresenceofblue
gramagrassandbuffalograss(Graul1975,GraulandWebster1976,KnopfandMiller1994).In
grasslandswherevegetationgrowstallerthanapproximatelythreeinchesinheight,Mountain
Ploversuseintensivelygrazedareas(GraulandWebster1976,Knopf1996),prairiedogtowns
(Knowlesetal.1982;KnowlesandKnowles1984,OlsonandEdge1985,Shackford1991),and
falloworrecentlyplowedagriculturalfields(Shackford1991,Shackfordetal.1999).
ClimateChangeVulnerabilityAssessmentforColoradoBLM231
CCVI Scoring
B1)Exposuretosealevelrise.Neutral.
B2a)Distributionrelativetonaturalbarriers..Neutral.Significantnaturalbarriersdonotexist
forthisspecies.TheMountainPloverisaGreatPlainsinhabitantandishighlyvolant,capableof
traversingmountainrangesandlargebodiesofwater.Itisaseasonalmigrant,whosehomeranges
averageover50hectaresinsize(KnopfandRupert1996).
B2b)Distributionrelativetoanthropogenicbarriers.Increase.Neutral.Significant
anthropogenicbarriersdonotexistforthisspecies.Thisbirdisavolantspeciesthatcanflyoveror
aroundpotentialanthropogenicbarriers.
B3)Impactoflandusechangesresultingfromhumanresponsestoclimatechange.Increase.
ThehabitatofthisGreatPlainsspeciesishighlysusceptibletopotentialdevelopmentofwind
farms/solarfarmsandbiofuelsproduction(AndresandStone2010).Inthefaceofrisingclimate
changeandcoststoextractfossilfuels,windenergydevelopmentisexpectedtoincreasewithinthe
rangeoftheMountainPloverinColorado(NRDC2014).
C1)Dispersalandmovements.Decrease.MountainPloverareknowntodisperseupto50
kilometersfromtheirnatalregions(KnopfandWunder2006).
C2ai)Predictedsensitivitytotemperature:historicalthermalniche.Neutral.Therange
occupiedbytheMountainploverintheassessedareahasexperiencedanaverage(51.7‐77°
F/31.8‐43.0°C)zonalmeanseasonaltemperatureoverthelast50years.
C2aii)Predictedsensitivitytotemperature:physiologicalthermalniche.Somewhatincrease.
Adultsactivelyshadechicksonhotdays,andadultsandchicksoftenseekshade(Knopfand
Wunder2006).Increasedtemperaturesassociatedwithclimatechangeintheassessedarea
(Melilloetal.2014)couldleadtoincreasedbroodrearingstressforMountainPlover.
C2bi)Predictedsensitivitytochangesinprecipitation,hydrology,ormoistureregime:
historicalhydrologicalniche.Somewhatdecrease.WithintheassessedareatheMountainPlover
hasexperiencedgreaterthanaverage(>40inches/1,016mm)precipitationvariationinthepast50
years.
C2bii)Predictedsensitivitytochangesinprecipitation,hydrology,ormoistureregime:
physiologicalhydrologicalniche.Somewhatdecrease.Adultsurvivalandnestsuccessishighest
duringdroughtperiods,butnestsuccessisalsoenhancedbycoolertemperatures(Dinsmore2008,
Dreitzetal.2012).Inthefuture,climatechangeisprojectedtoincreasetemperatures,butitwill
alsoincreasedroughtfrequency(Melilloetal.2014),whichmayincreaseadultsurvivaland
recruitmentofyoungMountainPlover.However,theinterplayofclimatechangeinduceddrought
andwarmingwithinprairieecosystemswillbedynamic,makingitdifficulttoassesshowthiswill
impactMountainploverpopulationtrendsovertime.
232ColoradoNaturalHeritageProgram©2015
C2c)Dependenceonaspecificdisturbanceregimelikelytobeimpactedbyclimatechange.
Somewhatdecrease.MountainPloverreactfavorablytofire,andwiththepredictedincreasein
wildfireintheassessedareaduetoclimatechange(Melilloetal.2014),thisshouldleadto
somewhatofadecreaseintheirvulnerabilitytohowclimatechangewillimpactthisindexfactor.In
somepartsoftheirrange,MountainPloversareattractedtoburnedgrasslandsinbreedingareas
fornestingandinnonbreedingareasforforagingandnightroosting(WunderandKnopf2003,
Knopf2008).MountainPloverresponsetoburnsisoftenquick,withbirdsappearingonfields
wherefiresarestillsmoldering(KnopfandWunder2006).Increaseddroughtassociatedwith
climatechangeintheaccessedareaisexpectedtoincreasewildfirefrequency(Melilloetal.2014),
potentiallybenefittingMountainPlover.
C2d)Dependenceonsnow‐coveredhabitats.Neutral.TheMountainPloverisnotdependenton
habitatswithice,snow,oronsnowpack.
C3)Restrictiontouncommongeologicalfeaturesorderivatives.Neutral.TheMountainPlover
isnotdependentuponanyuncommongeologicalelements.
C4a)Dependenceonotherspeciestogeneratehabitat.SomewhatIncrease.TheMountain
Ploverusesareasofshortgrassesthathavebeengrazedbyprairiedogs,cattleandother
herbivores(Dinsmore2003).
C4b)Dietaryversatility.Neutral.MountainPloverareopportunisticforagersthatfeedonabroad
rangeofinsects(KnopfandWunder2006).
C4d)Dependenceonotherspeciesforpropaguledispersal.Neutral.TheMountainPloverisa
self‐disperser.
C4e)Formspartofaninterspecificinteractionnotcoveredby4a‐d.Neutral.Noother
interspecificinteractionsareimportanttothepersistenceoftheMountainPlover.
C5a)Measuredgeneticvariation.SomewhatDecrease.MountainPloverpopulationsexhibit
considerablegeneticmixing,whichresultsinhighgeneticvariabilitywithinpopulations(Oyler‐
McCanceetal.2005).
C5b)Occurrenceofbottlenecksinrecentevolutionaryhistory.Unknown.
C6)Phenologicalresponsetochangingseasonaltemperatureandprecipitationdynamics.
Unknown.
D1)Responsetorecentclimatechange.Unknown.
D2)Modeledfuturechangeinpopulationorrangesize.Unknown.
D3)Overlapofmodeledfuturerangewithcurrentrange.Unknown.
D4)Protectedareas.Unknown.
ClimateChangeVulnerabilityAssessmentforColoradoBLM233
Literature Cited
Andres,B.A.,andK.L.Stone.2010.ConservationPlanfortheMountainPlover(Charadriusmontanus),Version1.1.
ManometCenterforConservationSciences,Manomet,Massachusetts.
Andrews,R.,andR.Righter.1992.Coloradobirds:areferencetotheirdistributionandhabitat.DenverMus.Nat.Hist.,
Denver.442pp.
Augustine,D.J.,andJ.D.Derner.2012.DisturbanceRegimesandMountainPloverHabitatinShortgrassSteppe:Large
HerbivoreGrazingDoesNotSubstituteforPrairieDogGrazingorFire.ManagementandConservation76:721‐728.
Dinsmore,S.J.2003.MountainPlover(Charadriusmontanus):atechnicalconservationassessment.[Online].USDAForest
Service,RockyMountainRegion.Available:http://www.fs.fed.us/r2/projects/scp/assessments/mountainplover.pdf
[1/23/2015].
Dinsmore,S.T.2008.InfluenceofdroughtonannualsurvivaloftheMountainPlover.TheCondor,110:45–54.
Dreitz,V.J.,R.Y.Conrey,andS.K.Skagen.2012.Droughtandcoolertemperaturesareassociatedwithhighernestsurvival
inMountainPlovers.AvianConservationandEcology:[online]URL:http://www.ace‐eco.org/vol7/iss1/art6/.
Graul,W.D.1975.BreedingbiologyoftheMountainPlover.WilsonBull.87:6‐31
Graul,W.D.,andL.E.Webster.1976.BreedingstatusoftheMountainPlover.Condor78:265‐267.
Knopf,F.L.1996.MountainPlover(Charadriusmontanus).inTheBirdsofNorthAmerica,No.211(A.PooleandF.Gill,
eds.).TheAcademyofNaturalSciences,Philadelphia,PA,andTheAmericanOrnithologists’Union,Washington,D.C.
Knopf,F.L.2008.MountainPloverstudies,PawneeNationalGrassland,1985–2007.Unpublishedreport,Colorado
DivisionofWildlife,Denver,CO.
Knopf,F.L.,andB.J.Miller.1994.Charadriusmontanus‐montane,grassland,orbare‐groundplover?Auk111:504‐506.
Knopf,F.L.andJ.R.Rupert.1996.ReproductionandmovementsofMountainPloversbreedinginColorado.Wilson
Bulletin108:28‐35.
Knopf,F.L.andM.B.Wunder.2006.MountainPlover(Charadriusmontanus),TheBirdsofNorthAmericaOnline(A.Poole,
Ed.).Ithaca:CornellLabofOrnithology;RetrievedfromtheBirdsofNorthAmericaOnline:
http://bna.birds.cornell.edu/bna/species/211doi:10.2173/bna.211.
Knowles,C.J.,andP.R.Knowles.1984.AdditionalrecordsofMountainPloversusingprairiedogtownsinMontana.Prairie
Naturalist16:183‐186.
Knowles,C.J.,C.J.Stoner,andS.P.Gieb.1982.Selectiveuseofblack‐tailedprairiedogtownsbyMountainPlovers.Condor
84:71‐74.
Melillo,J.M.,T.C.Richmond,andG.W.Yohe,Eds.,2014:ClimateChangeImpactsintheUnitedStates:TheThirdNational
ClimateAssessment.U.S.GlobalChangeResearchProgram,841pp.doi:10.7930/J0Z31WJ2.
NaturalResourcesDefenseCouncil(NRDC).2014.RenewableenergyforAmerica.
http://www.nrdc.org/energy/renewables/energymap.asp
Olson,S.L.,andD.Edge.1985.NestsiteselectionbyMountainPloversinnorthcentralMontana.J.RangeManage.38:280‐
282.
Oyler‐McCance,S.J.,J.St.John,F.L.Knopf,andT.W.Quinn.2005.PopulationgeneticanalysisofMountainPloverusing
mitochondrialDNAsequencedata.Condor107:354–362.
234ColoradoNaturalHeritageProgram©2015
Shackford,J.S.1991.BreedingecologyoftheMountainPloverinOklahoma.Bull.OklahomaOrnithol.Soc.24:9‐13.
Shackford,J.S.,D.M.Leslie,Jr.,andW.D.Harden.1999.Range‐wideuseofcultivatedfieldsbyMountainPloversduring
thebreedingseason.J.FieldOrnithol.70:114‐120.
Wunder,M.B.,andF.L.Knopf.2003.TheImperialValleyofCaliforniaiscriticaltowinteringMountainPlovers.Journalof
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
ClimateChangeVulnerabilityAssessmentforColoradoBLM235
Northern Goshawk
Accipitergentilis
G5/S3B
Family:Accipitridae
Climate Vulnerability Rank: Moderately Vulnerable
ThisColoradostatewiderankisbasedon:theprojectedincreaseintemperatureanddroughtfor
theassessedarea,selectionofcoolmicroclimatesfornestplacement,dependenceonold‐forest
structurethatmaybethreatenedbyincreasedfrequencyofwildfirecausedbydroughtand
warming,andlowlevelsofgeneticvariabilityquestioningthegoshawksadaptabilitytoachanging
environment.Regionalannualaveragetemperaturesareprojectedtoriseby2.5°Fto5.5°Fby
2041‐2070andby5.5°Fto9.5°Fby2070‐2099withcontinuedgrowthinglobalemissions(A2
emissionsscenario),withthegreatestincreasesinthesummerandfall(Melilloetal.2014).Under
acontinuationofcurrentrisingemissionstrends(A2),reducedwinterandspringprecipitationis
consistentlyprojectedforthesouthernpartoftheSouthwestby2100elevatingthepotentialfor
wildfire(Melilloetal.2014).
Distribution:TheNortherngoshawkisfoundthroughoutthestateofColoradoabove7500feetin
elevation(AndrewsandRighter1992).TheColoradoBreedingBirdAtlas(Kingery1998)shows
goshawkstobewelldistributedintheSanJuanMountainsandacrossthenorthernmountain
ranges.Habitat:InnorthwesternColorado,northerngoshawkstypicallynestinaspen,sometimes
inconiferstandslessthan100yearsold,andupto10,000feetinelevation(Kingery1998).
Goshawkstendtochoosenesttreesonshallowslopes,flatbenchesinsteepcountry,andfluvial
pansonsmallstreamjunctions(Kingery1998).
CCVI Scoring
B1)Exposuretosealevelrise.Neutral.
236ColoradoNaturalHeritageProgram©2015
B2a)Distributionrelativetonaturalbarriers..Neutral.Significantnaturalbarriersdonotexist
forthisspecies.Thisraptorisavolantspeciesthatcantraversemountainrangesandlargebodies
ofwater(NatureServe2014).
B2b)Distributionrelativetoanthropogenicbarriers..Neutral.Significantanthropogenic
barriersdonotexistforthisspecies.Thisraptorisavolantspeciesthatcanflyoveroraround
potentialanthropogenicbarriers(NatureServe2014).
B3)Impactoflandusechangesresultingfromhumanresponsestoclimatechange.Neutral.
AlthoughNorthernGoshawkhavebeenreportedtobeatriskofcollisionwithwindturbinesduring
migration(Brandes2005)onlyasmallportionoftheirrangeintheassessedareaissuitablefor
windenergydevelopmentandtherearenotimportantflywaysforthisraptorwithinthepotential
areasofwinddevelopment(NRDC2014).Thisisalowconcernfortheraptorwithintheassessed
area.
C1)Dispersalandmovements.Decrease.NorthernGoshawksreadilydispersemorethan10
kilometersfromhatchingsitetobreedingareasandhavehomerangesthatarefromthe100sto
1000sofhectaresinsize(SquiresandReynolds1997).
C2ai)Predictedsensitivitytotemperature:historicalthermalniche.Neutral.Therange
occupiedbytheNortherngoshawkintheassessedareahasexperiencedanaverage(51.7‐77°
F/31.8‐43.0°C)zonalmeanseasonaltemperatureoverthelast50years.
C2aii)Predictedsensitivitytotemperature:physiologicalthermalniche.Somewhatincrease.
InsouthernportionsoftheGoshawkrangeincludingtheassessedareagoshawknestareas
typicallyhavenortherlyaspectsindicatingaselectionforcoolermicroclimates(USFWS1998).
Climateprojectionssuggestthatsummertemperaturesintheassessedareawillincreasefrom6°F
morethan10°Fbytheendofthecenturyunderahigheremissionsscenario(Karletal.2009),
whichcouldmakethegoshawkmorevulnerabletoclimatechangeintheassessedarea.
C2bi)Predictedsensitivitytochangesinprecipitation,hydrology,ormoistureregime:
historicalhydrologicalniche.Somewhatincrease.WithintheassessedareatheNorthern
Goshawkhasexperiencedslightlylowerthanaverage(20‐30inches/255‐508mm)precipitation
variationinthepast50years.
C2bii)Predictedsensitivitytochangesinprecipitation,hydrology,ormoistureregime:
physiologicalhydrologicalniche.Somewhatdecrease.Reproductivesuccessseemstobe
negativelyimpactedbyincreasedspringprecipitationandpositivelyinfluencedbywarmer
temperatures(Kennedy2003,Patla2997)andwithincreasingtemperaturesanddroughtprojected
fortheassessedarea(Karletal.2009)thiscouldpositivelyimpactrecruitment.However,
populationgrowthratesaremostsensitivetochangesinadultsurvivalratesandchangesthat
influenceadultsurvivalwouldprobablyhaveagreaterinfluenceonpopulationpersistence
(Kennedy2003).
ClimateChangeVulnerabilityAssessmentforColoradoBLM237
C3)Restrictiontouncommongeologicalfeaturesorderivatives.Neutral.Thegoshawkisnot
dependentuponanyuncommongeologicalelements.
C2c)Dependenceonaspecificdisturbanceregimelikelytobeimpactedbyclimatechange.
Increase.Goshawksaredependentonold‐foreststructureanddecliningprecipitationcoupledwith
increasingtemperaturesanddroughtintheassessedareaisprojectedtoincreasetheareaburned
bywildfire(Karletal.2009).Thispotentialthreattooldgrowthforestisaconcernforgoshawks
(Boyceetal.2006).
C2d)Dependenceonsnow‐coveredhabitats.Neutral.Thegoshawkisnotdependentonhabitats
withice,snow,oronsnowpack.
C3)Restrictiontouncommongeologicalfeaturesorderivatives.Neutral.Thegoshawkisnot
dependentuponanyuncommongeologicalelements.
C4a)Dependenceonotherspeciestogeneratehabitat.Neutral.Thegoshawkisnotdependent
onanyotherspeciestocreatesuitablehabitatforitsexistence.
C4b)Dietaryversatility.Neutral.Thegoshawkcapturesawidevarietyofpreyandisclassifiedas
apreygeneralist(SquiresandReynolds1997),typicallypreyingonasuiteof8to15species
(Reynoldsetal.1992).
C4d)Dependenceonotherspeciesforpropaguledispersal.Neutral.Thegoshawkisaself‐
disperser.
C4e)Formspartofaninterspecificinteractionnotcoveredby4a‐d.Neutral.Noother
interspecificinteractionsareimportanttothepersistenceofthegoshawk.
C5a)Measuredgeneticvariation.SomewhatIncrease.Thegoshawkexhibitshighhaplotype
diversityacrosspopulationsinNorthAmerica,butlownucleotidediversitywithinpopulations
includingtheRockyMountainpopulation,whichisgeneticallydifferentiatedfromeasternand
otherwesternpopulationsoftheraptor(BayarddeVoloetal.2013).
C5b)Occurrenceofbottlenecksinrecentevolutionaryhistory.Unknown.
C6)Phenologicalresponsetochangingseasonaltemperatureandprecipitationdynamics.
Unknown.
D1)Responsetorecentclimatechange.Unknown.
D2)Modeledfuturechangeinpopulationorrangesize.Unknown.
D3)Overlapofmodeledfuturerangewithcurrentrange.Unknown.
D4)Protectedareas.Unknown.
238ColoradoNaturalHeritageProgram©2015
Literature Cited
Andrews,R.,andR.Righter.1992.Coloradobirds:areferencetotheirdistributionandhabitat.DenverMus.Nat.Hist.,
Denver.442pp.
BayarddeVolo,S.,R.T.Reynolds,S.A.Sonsthagen,S.L.TalbotandM.F.Antolin.2013.Phylogeny,postglacialgeneflow,and
populationhistoryofNorthAmericanNorthernGoshawk(Accipitergentilis).TheAuk130:342−354.
Boyce,D.A.,Jr.,R.T.ReynoldsandR.T.Graham.2006.Goshawkstatusandmanagement:Whatdoweknow,whathavewe
done,wherearewegoing?In:Morrison,Michael,ed.Thenortherngoshawk:atechnicalassessmentofitsstatusecology,
andmanagement.StudiesinAvianBiology.31:312‐325.
Brandes,D.2005.WindpowerdevelopmentandraptormigrationintheCentralAppalachians.HawkMigrationStudies
Spring2005:20‐25.
Karl,T.R.,J.M.Melillo,andT.C.Peterson,(eds.).2009.GlobalClimateChangeImpactsintheUnitedStates.Cambridge
UniversityPress.
Kennedy,P.L.2003.NorthernGoshawk(Accipitergentilesatricapillus):atechnicalconservationassessment.[Online].
USDAForestService,RockyMountainRegion.Available:
http://www.fs.fed.us/r2/projects/scp/assessments/northerngoshawk.pdf[1/22/2015].
Kingery,H.E.(editor)1998.Coloradobreedingbirdatlas.ColoradoBreedingBirdAtlasPartnership,Denver.Colorado.
Melillo,J.M.,T.C.Richmond,andG.W.Yohe,Eds.,2014:ClimateChangeImpactsintheUnitedStates:TheThirdNational
ClimateAssessment.U.S.GlobalChangeResearchProgram,841pp.doi:10.7930/J0Z31WJ2.
NatureServe.2014.NatureServeExplorer:Anonlineencyclopediaoflife[webapplication].Version7.1.NatureServe,
Arlington,Virginia.Availablehttp://explorer.natureserve.org.(Accessed:January21,2015).
NRDC(NaturalResourcesDefenseCouncil).2014.RenewableenergyforAmerica.
http://www.nrdc.org/energy/renewables/energymap.asp
Patla,S.M.1997.Nestingecologyandhabitatofthenortherngoshawkinundisturbedandtimberharvestareasonthe
TargheeNationalForest,GreaterYellowstoneecosystem.M.S.Thesis,IdahoStateUniversity,Pocatello,ID.
Reynolds,R.T.,R.T.Graham,M.H.Reiser,RL.Bassett,P.L.Kennedy,D.A.Boyce,G.Goodwin,R.Smith,andE.L.Fisher.1992.
ManagementrecommendationsforthenortherngoshawkinthesouthwesternUnitedStates.U.S.D.A.For.Serv.Gen.Tech.
Rep.RM‐217.RockyMt.For.andRangeExp.Stn.FortCollins,CO
Squires,J.R.andR.T.Reynolds.1997.NorthernGoshawk(Accipitergentilis),TheBirdsofNorthAmericaOnline(A.Poole,
Ed.).Ithaca:CornellLabofOrnithology;RetrievedfromtheBirdsofNorthAmericaOnline:
http://bna.birds.cornell.edu/bna/species/298doi:10.2173/bna.298
U.S.FishandWildlifeService(USFWS).1998.Statusreviewofthenortherngoshawkintheforestedwest.Unpublished
Report.OfficeofTechnicalSupport,ForestResources,PortlandOregon.Alsoavailableonlineat
http://pacific.fws.gov/news/pdf/gh_sr.pdf.

ClimateChangeVulnerabilityAssessmentforColoradoBLM239
Western Snowy Plover
Charadriusalexandrinusnivosus
G3T3/S1B
Family:Charadriidae
Climate Vulnerability Rank: Highly Vulnerable
ThisColoradostate‐widerankisbasedonthefollowingfactors:1)naturalbarrierstomovement;
2)potentialincreaseinwindenergydevelopmentinbreedinghabitat;3)relianceonalkali‐covered
playasandsandymarginsofreservoirsthatmaybevulnerabletodryingduetoprojectedwarmer
temperatures;4)potentialrelianceonseasonalwetlandscreatedbyspringrunoffthatmaybe
alteredduetoclimatechange;5)lowamountsofgeneticdifferentiation.
Distribution:TheWesternSnowyPlover(SnowyPloverhereafter)isasmallshorebirdthatbreeds
onthePacificcoastfromsouthernWashingtontosouthernBajaCalifornia,Mexico,andininterior
westernstatesincludingUtah,Idaho,NevadaandColorado(USFWS2012).InColorado,Snowy
Ploversnestonalkali‐coveredplayasintheSanLuisValley,aswellasalongsandyshoresof
constructedreservoirsinthesoutheasterncornerofthestateintheLowerArkansasRiverBasin
(AndrewsandRighter1992;ColoradoBirdAtlasPartnership1998).Theytypicallyarrivein
Coloradoinmid‐Aprilanddepartstartingfrommid‐JulyintoOctober(AndrewsandRighter1992).
Habitat:InColorado,SnowyPloversnestonalkali‐coveredplayasintheSanLuisValley,aswellas
alongsandyshoresofreservoirsintheLowerArkansasRiverBasin.Elevation:Noinformationis
availableontheelevationrangeofSnowyPloverinColorado,butbasedondistribution,thespecies
likelybreedsatelevationsrangingfrom4,000ftto8,000ft.
EcologicalSystem:ShortgrassPrairie,GreasewoodShrublands
240ColoradoNaturalHeritageProgram©2015
CCVI Scoring
B1)Exposuretosealevelrise.Neutral.Sandyoceanbeachesofferhabitatforsnowyplover,and
thesemaybelosttosealevelrise.However,theassessmentareaforthisCCVIislimitedto
Colorado,sosealevelriseisnotconsideredhere.
B2a)Distributionrelativetonaturalbarriers.Neutral.Thisspeciesishighlymobile.
B2b)Distributionrelativetoanthropogenicbarriers.Neutral.Thisspeciesishighlymobile.
B3)Impactoflandusechangesresultingfromhumanresponsestoclimatechange.
SomewhatIncrease.SnowyPloverareknowntonestintheSanLuisValleyandineasternColorado
alongtheArkansasRiver(ColoradoBirdAtlasPartnership1998).AccordingtoDepartmentof
Energywindresourcemaps,theeasternquarterofColoradoneartheNewMexicoandNebraska
bordershaveexcellentwindresources(DOE2004).Windturbinescancausedirectimpactstobirds
viacollisionsthatresultininjuryormortality(Kunzetal.2007;Kuvleskyetal.2007),aswellas
indirectimpactsviahabitatlossandbarrierstomovement(DrewittandLangston2006;Kuvlesky
etal.2007;Pruettetal.2009;Kieseckeretal.2011).
C1)Dispersalandmovements.Decrease.Thisspeciesishighlymobile.SnowyPloversthatbreed
intheGreatPlainswinterontheGulfofMexicocoast(Pageetal.2009).
C2ai)Predictedsensitivitytotemperature:historicalthermalniche.Neutral.Consideringthe
meanseasonaltemperaturevariationforoccupiedcells,thespecieshasexperiencedaverage(57.1‐
77°F/31.8‐43.0°C)temperaturevariationinthepast50years.
C2aii)Predictedsensitivitytotemperature:physiologicalthermalniche.Neutral.Thisspecies
isnotlimitedtocoolorcoldhabitats.
C2bi)Predictedsensitivitytochangesinprecipitation,hydrology,ormoistureregime:
historicalhydrologicalniche.SomewhatDecrease.Consideringtherangeofmeanannual
precipitationacrossoccupiedcells,thespecieshasexperiencedgreaterthanaverage(>40
inches/1,016mm)precipitationvariationinthepast50years.
C2bii)Predictedsensitivitytochangesinprecipitation,hydrology,ormoistureregime:
physiologicalhydrologicalniche.GreatlyIncrease.SnowyPloversnestonalkali‐coveredplayas
intheSanLuisValley,aswellasalongsandyshoresofreservoirsintheLowerArkansasRiver
Basin.TheSanLuisValleyislocatedintheRioGrandeRiverBasin.Manywetlandsinthisbasinare
dependentonsnow‐meltfromthesurroundingmountains,andthesewetlandsareexpectedtobe
moreacutelyaffectedthanotherecosystemsinthearea(USFWS2012).Climatemodelsprojecta
rangeof‐28%to+11%inannualrunofffortheRioGrandeBasin,andarangeof‐10%to+19%for
theArkansasRiverBasinformid‐century(Lukasetal.2014).Furthermore,changingdemandsfor
waterintheseriverbasinsmayresultingreaterfluctuationsinreservoirlevelsintheseareas,
whichinturncouldleadtothefloodingofreservoirshorelinesandresultinglossofSnowyPlover
nestinghabitat.Lastly,increasedgroundwaterpumpingforagriculturecouldleadtoareductionin
availablesurfacewaterandalossofSnowyPlovernestinghabitat(Busby2002).
ClimateChangeVulnerabilityAssessmentforColoradoBLM241
C2c)Dependenceonaspecificdisturbanceregimelikelytobeimpactedbyclimatechange.
SomewhatIncrease.SnowyPloversintheArkansasBasinhavebeendocumentednestingonthe
shorelinesofconstructedreservoirs,butintheSanLuisValley,thealkaliflatsthatprovidenesting
habitatarelikelytiedtomoreseasonalhydroperiodsassociatedwithspringrunoff.
C2d)Dependenceonsnow‐coveredhabitats.SomewhatIncrease.IntheSanLuisValley,runoff
fromsnowmeltprovidesflowstowetlandsthatprovidehabitatforSnowyPlover(Laubhanand
Gammonley2000).
C3)Restrictiontouncommongeologicalfeaturesorderivatives.SomewhatIncrease.The
SnowyPloveroccursonalkaliflatsaroundreservoirsduringthebreedingseason,whilemigrants
occuronmudflatsandsandyshorelines(AndrewsandRighter1992).Furthermore,SnowyPlovers
intheGreatPlainsfrequentlynestnearwaterbodiesthatcontainhighsalinitylevels,whichthey
mayuseforevaporativecoolingduringperiodsofhightemperatures(Purdue1976).
C4a)Dependenceonotherspeciestogeneratehabitat.Neutral.
C4b)Dietaryversatility.Neutral.IntheGreatPlains,SnowyPloverfeedonavarietyof
invertebratesincludingflies(Ephydrasp.),beetles(Blediussp.,Cicindelasp.),andmanyterrestrial
insectsblownfromsurroundingareasincludinggrasshoppers,lepidopterans,andbeetles(Busby
2002;Purdue1976,GroverandKnopf1982).
C4c)Pollinatorversatility(Plantsonly,notapplicable).
C4d)Dependenceonotherspeciesforpropaguledispersal.Neutral.
C4e)Formspartofaninterspecificinteractionnotcoveredby4a‐d.Unknown.
C5a)Measuredgeneticvariation.SomewhatIncrease.Geneticstudieshaverevealedlowamounts
ofgeneticdifferentiationamongpopulationsofSnowyPlovers,withalmostallvariabilityfound
withinpopulations(Funketal.2007).
C5b)Occurrenceofbottlenecksinrecentevolutionaryhistory.Neutral.Noevidencefora
populationbottleneckwasfoundinageneticstudyofGreatBasin,Midwest,GulfCoast,andPacific
CoastSnowyPloverpopulations(Funketal.2007).
C6)Phenologicalresponsetochangingseasonaltemperatureandprecipitationdynamics.
Unknown.
D1)Responsetorecentclimatechange.Unknown.
D2)Modeledfuturechangeinpopulationorrangesize.Unknown.
D3)Overlapofmodeledfuturerangewithcurrentrange.Unknown.
D4)Protectedareas.Unknown.
242ColoradoNaturalHeritageProgram©2015
Literature Cited
Andrews,R.A.,andR.Righter.1992.Coloradobirds.DenverMuseumofNaturalHistory.Denver,Co.Pp27.
Busby,W.H.2002.KansasRecoveryPlanfortheSnowyPlover(Charadriusalexandrinus).KansasBiologicalSurveyReport
toKansasDepartmentofWildlifeandParks.44pg.
ColoradoBirdAtlasPartnership,RadeauxandColoradoDivisionofWildlife.1998.ColoradoBreedingBirdAtlas.Denver,
Colorado:ColoradoBirdAtlasPartnership.636pg.
DepartmentofEnergy(DOE).2004.WINDExchange.ColoradoWindResourceMap.Availableonlineat
http://apps2.eere.energy.gov/wind/windexchange/wind_resource_maps.asp?stateab=co.AccessedFeb2,2015.
Drewitt,A.L.andR.H.W.Langston.2006.AssessingtheImpactsofWindFarmsonBirds.Ibis148:29‐42.
Funk,W.C.,T.D.Mullins,andS.M.Haig.2007.Conservationgeneticsofsnowyplovers(Charadriusalexandrinus)inthe
WesternHemisphere:populationgeneticstructureanddelineationofsubspecies.ConservationGenetics8:1287–1309.
Grover,P.B.,andF.L.Knopf.1982.HabitatrequirementsandbreedingsuccessofCharadriaformbirdsnestingatSalt
PlainsNationalWildlifeRefuge,Oklahoma.JournalofFieldOrnithology53:139‐148.
Kiesecker,J.M.,J.S.Evans,J.Fargione,K.Doherty,K.R.Foresman,T.H.Kunz,D.Naugle,N.P.Nibbelink,andN.D.Nieumuth.
2011.Win‐winforwindandwildlife:avisiontofacilitatesustainabledevelopment.PlosONE6:e17566.
Kunz,T.H.,E.B.Arnett,B.M.Cooper,W.P.Erickson,R.P.Larkin,T.Mabee,M.L.Morrison,M.D.Strickland,andJ.M.
Szewczak.2007.Assessingimpactsofwind‐energydevelopmentonnocturnallyactivebirdsandbats:aguidance
document.JournalofWildlifeManagement71:2449–4486.http://www.wind‐watch.org/documents/wp‐
content/uploads/wild‐71‐08‐45.pdf.
Kuvlesky,W.P.Jr.,L.A.Brennan,M.L.Morrison,K.K.Boydston,B.M.BallardandF.C.Bryant.2007.WindEnergy
DevelopmentandWildlifeConservation:ChallengesandOpportunities.JournalofWildlifeManagement71(8):2487‐
2498.
Laubhan,M.K.,andJ.H.Gammonley.2000.DensityandforaginghabitatselectionofwaterbirdsbreedingintheSanLuis
ValleyofColorado.JournalofWildlifeManagement64:808‐819.
Lukas,J.,J.Barsugli,N.Doesken,I.Rangwala,andK.Wolter.2014.ClimateChangeinColorado:ASynthesistoSupport
WaterResourcesManagementandAdaptation.AReportfortheColoradoWaterConservationBoard.WesternWater
Assessment.
Page,G.W.,L.E.Stenzel,G.W.Page,J.S.Warriner,J.C.WarrinerandP.W.Paton.2009.SnowyPlover(Charadrius
alexandrinus),TheBirdsofNorthAmericaOnline(A.Poole,Ed.).Ithaca:CornellLabofOrnithology;Retrievedfromthe
BirdsofNorthAmericaOnline:http://bna.birds.cornell.edu/bna/species/154.
Pruett,C.L.,M.A.Patten,andD.H.Wolfe.2009.AvoidanceBehaviorbyPrairieGrouse:ImplicationsforDevelopmentof
WindEnergy.ConservationBiology23(5)1253‐1259.
Purdue,J.R.1976.AdaptationsoftheSnowyPloverontheGreatSaltPlains,Oklahoma.SouthwesternNaturalist.21:347‐
357.
U.S.FishandWildlifeService.SanLuisValleyConservationArea,ColoradoandNewMexico.2012.DraftEnvironmental
AssessmentandLandProtectionPlan.MountainPrairieRegion.Availableonlineathttps://www.fws.gov/mountain‐
prairie/refuges/lpp_PDFs/slv_lppdraft_all.pdf 
ClimateChangeVulnerabilityAssessmentforColoradoBLM243
Western Yellow‐billed Cuckoo
Coccyzusamericanusoccidentalis
G5T2T3/S1B
Family:Cuculidae
Climate Vulnerability Rank: Moderately Vulnerable
ThisColoradostatewiderankisbasedon:narrowhabitatrequirementsanddifficultiesindispersal
byjuvenilesandadultsbetweenpatchesofsuitableriparianhabitat,increaseddryinganddrought
projectedduetoclimatechangefortheassessedarea,dryingassociatedwithglobalclimatechange
causingincreasedwaterwithdrawalforhumanconsumptionresultinginadditionallossand
fragmentationofriparianbreedinghabitat,increasedwildfireduetoincreasedfrequencyof
droughtinhistoricallywildfirefreeriparianhabitat,andprojectedincreasesintamariskinvasion
intosuitableriparianhabitatduetoclimatechange.Climatemodelsprojectincreasedwarmingand
droughtacrosstheassessedareawithannualaveragetemperaturesrisingby2.5°Fto5.5°Fby
2041‐2070andby5.5°Fto9.5°Fby2070‐2099withcontinuedgrowthinglobalemissions(A2
emissionsscenario),withthegreatestincreasesinthesummerandfall(Melilloetal.2014).
Projectionsofprecipitationchangesarelesscertain,butunderacontinuationofcurrentrising
emissionstrends(A2),reducedwinterandspringprecipitationisconsistentlyprojectedforthe
southernpartoftheSouthwestby2100(Melilloetal.2014).Theseprojectedchangesinclimateare
predictedtohavedramaticeffectsonthedistribution,quantity,andqualityofsuitableriparian
habitatavailableforbreeding,negativelyimpactingpopulationsofthecuckoowithintheassessed
area.
Distribution:TheRockyMountainBirdObservatoryconductedsurveysforcuckoosinwestern
Coloradoduringthesummersof2008through2011andfoundthemalongtheNorthForkofthe
GunnisonRiver(DeltaCounty),theColoradoRiver(MesaCounty),nearNucla(MontroseCounty),
andtheYampaRiver(MoffatCounty)(Beason2012).Ahandfulofincidentaldetectionswerealso
recordedduringthistime,butitwasconcludedthatthespeciesisaveryrarebreederinwestern
Coloradoaftersurveyswerecompleted.Habitat:Ariparianspecies,thewesternyellow‐billed
244ColoradoNaturalHeritageProgram©2015
cuckoobreedsinlow‐tomoderate‐elevationnativeforestsliningtheriversandstreamsofthe
westernUnitedStates.Cottonwoodwillowforests(Populusspp.‐Salixspp.)aremostoftenused,
althoughotherripariantreespeciescanbeimportantcomponentsofbreedinghabitataswell,such
asalder(Alnusspp.),boxelder(Acernegundo),mesquite(Prosopisspp.),Arizonawalnut(Juglans
major),Arizonasycamore(Platanuswrightii),oak(Quercusspp.),netleafhackberry(Celtis
reticulata),velvetash(Fraxinusvelutina),Mexicanelderberry(Sambucusmexicanus),seepwillow
(Baccharisglutinosa),andoccasionally,tamarisk(Tamarixspp.).
CCVI Scoring
B1)Exposuretosealevelrise.Neutral.
B2a)Distributionrelativetonaturalbarriers..Neutral.Significantnaturalbarriersdonotexist
forthisspecies.Thecuckooisavolantlongdistantmigratorthatcantraversemountainrangesand
largebodiesofwater.
B2b)Distributionrelativetoanthropogenicbarriers.Increase.Somewhatincreasetoincrease.
Habitatdestruction,modification,anddegradationfromdamconstructionandoperations;water
diversions;riverflowmanagement;streamchannelizationandstabilization;conversionto
agriculturaluses,suchascropsandlivestockgrazingintheassessmentareaareconsidered
barrierstodispersalbyjuvenileandadultyellow‐billedcuckoos(USFWS2014).
B3)Impactoflandusechangesresultingfromhumanresponsestoclimatechange.Increase.
Modificationstohydrology(impoundments,channelization,andalterationofriverflows,and
surfaceandgroundwaterwithdrawal)resultincuckoohabitatlossandfragmentation(USFWS
2014).Thedryingtrendassociatedwithglobalclimatechangemayresultinmoredams,levees,
waterwithdrawalsorotheractivitiestoensurefreshwaterforhumanconsumption,whichmay
resultinadditionalhabitatlossandfragmentation(USFWS2014).
C1)Dispersalandmovements.Somewhatdecreasetodecrease.Limiteddataondispersal
suggestshighsitefidelitywithmatingbirdsreturningtotheirpastnestingsiteswhilenatalbirdsdo
disperseupto205metersformalesand33,315metersforfemales(McNeiletal.2013).
Additionallycuckoosarelong‐distancemigrants,althoughdetailsoftheirmigrationpatternsare
notwellknown(Hughes1999).Matedpairsalsohavelargehomerangesthatvaryinsizefrom6‐
55hectares(Halterman2009).
C2ai)Predictedsensitivitytotemperature:historicalthermalniche.Neutral.Therange
occupiedbytheWestern‐yellowbilledcuckoointheassessedareahasexperiencedanaverage
(51.7‐77°F/31.8‐43.0°C)zonalmeanseasonaltemperatureoverthelast50years.
C2aii)Predictedsensitivitytotemperature:physiologicalthermalniche.Somewhatincrease
toincrease.Thereisnodirectevidencethatcuckoosrequirecoolmicroclimatesfornesting,butin
thewesternU.S.theyarerestrictedtoriparianhabitatswiththickshadedoverstorythatareof
higherhumiditythanthesurroundingaridlandscape(Hughs1999,Wiggins2005).
ClimateChangeVulnerabilityAssessmentforColoradoBLM245
C2bi)Predictedsensitivitytochangesinprecipitation,hydrology,ormoistureregime:
historicalhydrologicalniche.Somewhatdecrease.Therangeoccupiedbythecuckoointhe
assessedareahasexperiencedgreaterthanaverage(>40inches/1,016mm)precipitation
variationinthepast50years.
C2bii)Predictedsensitivitytochangesinprecipitation,hydrology,ormoistureregime:
physiologicalhydrologicalniche.Greatlyincrease.inthewesternU.S.thecuckooisrestrictedto
riparianhabitatswiththickshadedoverstorythatareofhigherhumiditythanthesurroundingarid
landscape(Hughs1999,Wiggins2005).Thehighersummertemperatures,earlierspringsnowmelt,
andlowersummerflowscausedbyclimatechange(Melilloetal.2014),willresultinbothshort‐
termandlong‐termlossofrequiredriparianhabitatfromexcessivewinterscouring,summer
drying,andwildfire(USFWS2014).
C2c)Dependenceonaspecificdisturbanceregimelikelytobeimpactedbyclimatechange.
Somewhatincrease.Thedryingprojectedfortheassessmentareaduetoclimatechangeisexpected
toincreasethefrequencyofwildfire(Melilloetal.2014).Historically,wildfirewasuncommonin
nativeriparianwoodlands(BuschandSmith1993)andtheexpectedincreasedincidenceof
wildfireintocuckoohabitatwillfurtherdegrade,isolate,orfragmentcuckoohabitat(USFWS2014).
C2d)Dependenceonsnow‐coveredhabitats.Neutral.Thecuckooisnotdependentonhabitats
withice,snow,oronsnowpack.
C3)Restrictiontouncommongeologicalfeaturesorderivatives.Neutral.Thecuckooisnot
dependentuponanyuncommongeologicalelements.
C4a)Dependenceonotherspeciestogeneratehabitat.Neutral.Thecuckooisnotdependenton
anyotherspeciestocreatesuitablehabitatforitsexistence.
C4b)Dietaryversatility.Neutraltosomewhatincrease.Cuckoosfeedonabroadrangeofitems,
butprimarilyonslowmovinginsectsincludinggrasshoppers,butterfliesandmoths,hemipteraand
beetles.However,larvaeofthefamilySphingidae(sphinxmoths)havebeennotedasanimportant
foodsourceforyellow‐billedcuckoos,andthelackofsuchpreyhasbeenimplicatedinthedecline
ofthewesternsubspecies.(Wiggins2005).
C4d)Dependenceonotherspeciesforpropaguledispersal.Neutral.Thecuckooisaself‐
disperser.
C4e)Formspartofaninterspecificinteractionnotcoveredby4a‐d.Somewhatincrease.
Throughoutmostofitsrange,habitatfortheWesternyellow‐billedcuckooisthreatenedbythe
conversionofnativeriparianwoodlandstoriparianvegetationdominatedbytamariskandother
nonnativevegetation(USFWS2014).Modelsbasedonprojectedclimatechangepredictthatthis
invasivetamariskwillbecomemoredominantinthisregionoverthenext100years(Kernsetal.
2009).
C5a)Measuredgeneticvariation.Unknown.
246ColoradoNaturalHeritageProgram©2015
C5b)Occurrenceofbottlenecksinrecentevolutionaryhistory.Unknown.
C6)Phenologicalresponsetochangingseasonaltemperatureandprecipitationdynamics.
Unknown.
D1)Responsetorecentclimatechange.Unknown.
D2)Modeledfuturechangeinpopulationorrangesize.Decrease.Winterrangeispredictedto
increaseby69%by2080(NAS2014).
D3)Overlapofmodeledfuturerangewithcurrentrange.Unknown.
D4)Protectedareas.Unknown.
Literature Cited
Beason,J.P.2012.2011SurveysforYellow‐billedCuckoosinWesternColorado.TechRep.R‐YBCUUSFWS‐09‐3.Rocky
MountainBirdObservatory,Brighton,Colorado.30pp.
Busch,D.E.andS.D.Smith.1993.Effectsoffireonwatersalinityrelationsofriparianwoodytaxa.Oecologia94a:186‐194
Halterman,M.M.2009.SexualDimorphism,DetectionProbability,HomeRange,andParentalCareintheYellow‐billed
Cuckoo.UniversityofNevadaPhD.Dissertation.Accessedonline[2/4/2015]at
http://search.proquest.com/docview/304943422.
Hughes,J.M.1999.Yellow‐billedCuckoo(Coccyzusamericanus),TheBirdsofNorthAmericaOnline(A.Poole,Ed.).Ithaca:
CornellLabofOrnithology;RetrievedfromtheBirdsofNorthAmericaOnline:
http://bna.birds.cornell.edu/bna/species/418
Kerns,B.K.,B.J.Naylor,M.Buonopane,C.G.ParksandB.Rogers.2009.Modelingtamarisk(Tamarixspp.)habitatand
climatechangeeffectsintheNorthwesternUnitedStates.InvasivePlantScienceandManagement,2:200‐215.
McNeil,S.E.,D.Tracy,J.R.StanekandJ.E.Stanek.2013.Yellow‐billedcuckoodistribution,abundanceandhabitatuseon
theLowerColoradoRivertributaries:2008‐2012summaryreport.LowerColoradoRiverMulti‐SpeciesConservation
Program.BureauofReclamation,
Melillo,J.M.,T.C.Richmond,andG.W.Yohe,Eds.,2014:ClimateChangeImpactsintheUnitedStates:TheThirdNational
ClimateAssessment.U.S.GlobalChangeResearchProgram,841pp.doi:10.7930/J0Z31WJ2.
NationalAudubonSociety(NAS).2014.Audubon’sBirdsandClimateChangeReport:APrimerforPractitioners.National
AudubonSociety,NewYork.Contributors:GaryLangham,JustinSchuetz,CandanSoykan,ChadWilsey,TomAuer,Geoff
LeBaron,ConnieSanchez,TrishDistler.Version1.2.Available:http://climate.audubon.org/birds/goleag/golden‐eagle
[1/29/2015].
Wiggins,D.2005.Yellow‐billedCuckoo(Coccyzusamericanus):atechnicalconservationassessment.[Online].USDA
ForestService,RockyMountainRegion.Available:
http://www.fs.fed.us/r2/projects/scp/assessments/yellowbilledcuckoo.pdf[2/4/2015].
U.S.FishandWildlifeService(USFWS).2014.EndangeredandThreatenedWildlifeandPlants;ProposedThreatened
StatusfortheWesternDistinctPopulationSegmentoftheYellow‐billedCuckoo(Coccyzusamericanus);FinalRule.
FederalRegister79(192:59992‐60038). 
ClimateChangeVulnerabilityAssessmentforColoradoBLM247
White‐faced Ibis
Plegadischihi
G5/S2B
Family:Threskiornithidae
Climate Vulnerability Rank: Moderately Vulnerable
ThisColoradostate‐widerankisbasedonthefollowingfactors:1)potentialwindfarm
developmentonColorado’seasternplainsand2)potentialdecreaseinrunoffandprecipitationthat
servesasawatersourceforwetlandsintheSanLuisValley.
Distribution:InColorado,individualsprimarilynestintheSanLuisValleyandonportionsofthe
easternplains,andaretypicallymigrantsintheeasternplainsandmountainparks(Andrewsand
Righter1992).Habitat:TheWhite‐FacedIbisisalarge,long‐leggedbirdthatinhabitsfreshwater
wetlandsandmarshes(FieldGuidetotheBirdsofNorthAmerica1999,Dark‐SmileyKeinath2003).
EcologicalSystem:ShortgrassPrairie;Wetlands
CCVI Scoring
B1)Exposuretosealevelrise.Neutral.
B2a)Distributionrelativetonaturalbarriers.Neutral.White‐facedIbisareahighlymobile
species,andindividualsthatsummerinColoradoundertakelongmigrationstowinterinsouthern
California,Louisiana,andMexico(Rosenbergetal.1991).
B2b)Distributionrelativetoanthropogenicbarriers.Neutral.SeeB2aabove.Thisspeciesis
highlymobile.
B3)Impactoflandusechangesresultingfromhumanresponsestoclimatechange.
SomewhatIncrease.White‐facedIbisareknowntonestintheSanLuisValleyandontheeastern
plainsofColorado(AndrewsandRighter1992).AccordingtoDepartmentofEnergywindresource
maps,theeasternquarterofColoradoneartheNewMexicoandNebraskabordershaveexcellent
©JohnBreltsch
248ColoradoNaturalHeritageProgram©2015
windresources(DOE2004).Windturbinescancausedirectimpactstobirdsviacollisionsthat
resultininjuryormortality(Kunzetal.2007;Kuvleskyetal.2007),aswellasindirectimpactsvia
habitatlossandbarrierstomovement(DrewittandLangston2006;Kuvleskyetal.2007;Pruettet
al.2009;Kieseckeretal.2011).
C1)Dispersalandmovements.Decrease.SeeB2a.Thisspeciesishighlymobile,andindividuals
thatsummerinColoradotravellongdistancestospendthewinterinthesouthernU.S.andMexico
(Rosenbergetal.1991).
C2ai)Predictedsensitivitytotemperature:historicalthermalniche.Neutral.Consideringthe
meanseasonaltemperaturevariationforoccupiedcells,White‐FacedIbisinColoradohas
experiencedaverage(57.1‐77°F/31.8‐43.0°C)temperaturevariationinthepast50years.
C2aii)Predictedsensitivitytotemperature:physiologicalthermalniche.Neutral.Thisspecies
isnotlimitedtocoolorcoldenvironments.Droughtcouldaffecttheavailabilityofwetlandhabitats,
butthisisvulnerabilityisscoredunderC2bii.
C2bi)Predictedsensitivitytochangesinprecipitation,hydrology,ormoistureregime:
historicalhydrologicalniche.Increase.Consideringtherangeofmeanannualprecipitationacross
occupiedcells,White‐FacedIbishasexperiencedsmall(4‐10inches/100‐254mm)precipitation
variationinthepast50years.
C2bii)Predictedsensitivitytochangesinprecipitation,hydrology,ormoistureregime:
physiologicalhydrologicalniche.Increase.Thisspeciesisawetlandobligatethatprefers(almost
exclusively)wetlandswithemergentvegetation(Dark‐SmileyandKeinath2003).Drought
conditionscancausedryingofemergentvegetationandsuitablenestinghabitats,causingbreeding
adultstorelocate.Furthermore,droughtcanmakeibiseggsandyoungmoresusceptibleto
predation(Dark‐SmileyandKeinath2003).InRioGrandeBasin,wetlandsdependentonsnow‐melt
fromthesurroundingmountains,areexpectedtobemoreacutelyaffectedthanotherecosystemsin
thearea(USFWS2012).Climatemodelsprojectarangeof‐28%to+11%inannualrunoffforthe
RioGrandeBasinformid‐century(Lukasetal.2014).
C2c)Dependenceonaspecificdisturbanceregimelikelytobeimpactedbyclimatechange.
SomewhatIncrease.Shallow,seasonallyfloodedwetlandscanprovideforaginghabitatforWhite‐
FaceIbis(LaubhanandGammonley2000).
C2d)Dependenceonsnow‐coveredhabitats.SomewhatIncrease.IntheSanLuisValley,runoff
fromsnowmeltprovidesflowstowetlandsthatprovidehabitatforWhite‐FacedIbis(Laubhanand
Gammonley2000).
C3)Restrictiontouncommongeologicalfeaturesorderivatives.Neutral.
C4a)Dependenceonotherspeciestogeneratehabitat.Neutral.
C4b)Dietaryversatility.Neutral.TheWhite‐FacedIbisfeedsprimarilyoncrustaceans,
earthworms,andaquaticinsects(SmileyandKeinath2003).
ClimateChangeVulnerabilityAssessmentforColoradoBLM249
C4c)Pollinatorversatility(Plantsonly,notapplicable).
C4d)Dependenceonotherspeciesforpropaguledispersal.Neutral.
C4e)Formspartofaninterspecificinteractionnotcoveredby4a‐d.Unknown.
C5a)Measuredgeneticvariation.Unknown.
C5b)Occurrenceofbottlenecksinrecentevolutionaryhistory.Unknown.
C6)Phenologicalresponsetochangingseasonaltemperatureandprecipitationdynamics.
Unknown.
D1)Responsetorecentclimatechange.Unknown.
D2)Modeledfuturechangeinpopulationorrangesize.Unknown.
D3)Overlapofmodeledfuturerangewithcurrentrange.Unknown.
D4)Protectedareas.Unknown.
Literature Cited
Andrews,R.A.,andR.Righter.1992.Coloradobirds.DenverMuseumofNaturalHistory.Denver,Co.Pp27.
Dark‐Smiley,D.D.andD.A.Keinath.2003.SpeciesAssessmentforWhite‐FacedIbis(PlegadisChihi)inWyoming.Prepared
forU.S.DepartmentoftheInterior.Cheyenne,Wyoming.59pp.
DepartmentofEnergy(DOE).2004.WINDExchange.ColoradoWindResourceMap.Availableonlineat
http://apps2.eere.energy.gov/wind/windexchange/wind_resource_maps.asp?stateab=co.AccessedFeb2,2015.
Drewitt,A.L.andR.H.W.Langston.2006.AssessingtheImpactsofWindFarmsonBirds.Ibis148:29‐42.
FieldGuidetotheBirdsofNorthAmerica,ThirdEdition.1999.NationalGeographicSociety,Washington,D.C.
Kiesecker,J.M.,J.S.Evans,J.Fargione,K.Doherty,K.R.Foresman,T.H.Kunz,D.Naugle,N.P.Nibbelink,andN.D.Nieumuth.
2011.Win‐winforwindandwildlife:avisiontofacilitatesustainabledevelopment.PlosONE6:e17566.
Kunz,T.H.,E.B.Arnett,B.M.Cooper,W.P.Erickson,R.P.Larkin,T.Mabee,M.L.Morrison,M.D.Strickland,andJ.M.
Szewczak.2007.Assessingimpactsofwind‐energydevelopmentonnocturnallyactivebirdsandbats:aguidance
document.JournalofWildlifeManagement71:2449–4486.http://www.wind‐watch.org/documents/wp‐
content/uploads/wild‐71‐08‐45.pdf.
Kuvlesky,W.P.Jr.,L.A.Brennan,M.L.Morrison,K.K.Boydston,B.M.BallardandF.C.Bryant.2007.WindEnergy
DevelopmentandWildlifeConservation:ChallengesandOpportunities.JournalofWildlifeManagement71(8):2487‐
2498.
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WaterResourcesManagementandAdaptation.AReportfortheColoradoWaterConservationBoard.WesternWater
Assessment.
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WindEnergy.ConservationBiology23(5)1253‐1259.
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
ClimateChangeVulnerabilityAssessmentforColoradoBLM251
Bluehead Sucker
Catostomusdiscobolus
G4/S4
Family:Catostomidae
Climate Vulnerability Rank: Highly Vulnerable
ThisColoradostate‐widerankisbasedonthefollowingfactors:1)barrierstomovement;2)
warmingstreamtemperaturesmayaffectblueheadsuckerthatgenerallyinhabitcoolstreams3)
potentialdeclineinrunoffandsubsequentdecreaseinflowsintheUpperColoradoRiverBasin;4)
relianceongravelbarsforspawning;5)lackofvariabilityinannualprecipitationinlast50years;
6)hybridizationwiththenonnativewhitesuckercouldaffectthegeneticintegrityofthespecies.
Distribution:InColorado,theblueheadsuckerisfoundthroughouttheUpperColoradoRiver
drainage.Habitat:InColorado,adultblueheadsuckermostoftenarefoundinswifter,higher
gradientstreams;larvalfishinhabitnear‐shore,lowvelocityhabitats(Childsetal.1998).Riffles
andpoolssupportalgaeandmacroinvertebratesthatareconsumedbyblueheadsuckers(Sigler
andSigler1996).Blueheadsuckeroccupywarmtocoolstreams(20˚C)withrockysubstrates
(SiglerandSigler1996;Bestgen2000).
EcologicalSystem:Streams
CCVI Scoring
B1)Exposuretosealevelrise.Neutral.
B2a)Distributionrelativetonaturalbarriers.Increase.Blueheadsuckerarefoundinthe
mainstemandtributariesoftheColoradoRiverwithinthestateofColorado(MillerandRees2000).
Thespeciescanoccurinhighgradientstreams.Waterfallscouldcreateupstreammovements
withinthesestreams.Althoughtheexactleapingabilitiesofblueheadsuckerarenotknown,many
252ColoradoNaturalHeritageProgram©2015
streamfishesarenotabletojumpaboveheightsof1.0‐1.5m(BjornnandReiser1991;Holtheetal.
2005).
B2b)Distributionrelativetoanthropogenicbarriers.Increase.Damsandimpoundmentsalong
theColoradoRiveranditstributariescreatebarriersforblueheadsuckermovement.Thisspecies
prefersswiftervelocity,highergradientstreamsanddoesnotdowellinimpoundments
(BezzeridesandBestgen2002).
B3)Impactoflandusechangesresultingfromhumanresponsestoclimatechange.Neutral.
C1)Dispersalandmovements.SomewhatDecrease.Morestudiesareneededtoinvestigate
movementpatternsofblueheadsucker.Someinvestigatorshavereportedthatthespecies
relativelysedentary,movingonlyafewkilometers(Vanicek1967,ReesandMiller2001),while
othersreportrecapturingindividuals19kmfromoriginalcapturelocations(HoldenandCrist
1981).
C2ai)Predictedsensitivitytotemperature:historicalthermalniche.Neutral.Consideringthe
meanseasonaltemperaturevariationforoccupiedcells,thespecieshasexperiencedaverage(57.1‐
77°F/31.8‐43.0°C)temperaturevariationinthepast50years.
C2aii)Predictedsensitivitytotemperature:physiologicalthermalniche.SomewhatIncrease.
Blueheadsuckerinhabitawidevarietyofriversystemsfromsmallcreekstolargerivers.Although
generallyinhabitingstreamswithcooltemperatures,theyhavebeenfoundinsmallcreekswith
highwatertemperatures(28degreesC)(Ptaceketal.2005,Smith1966).
C2bi)Predictedsensitivitytochangesinprecipitation,hydrology,ormoistureregime:
historicalhydrologicalniche.SomewhatDecrease.Speciesshowsapreferenceforenvironments
towardthewarmerendofthespectrum
C2bii)Predictedsensitivitytochangesinprecipitation,hydrology,ormoistureregime:
physiologicalhydrologicalniche.SomewhatIncrease.Highbaseflowsareimportantforthe
reproductionsuccessofblueheadsucker(AndersonandStewart2007).Mostpublishedresearch
indicatesadeclineinrunoffintheUpperColoradoRiverBasinbythemid‐to‐late21stcentury(Ray
etal.2008,Lukasetal.2014).
C2c)Dependenceonaspecificdisturbanceregimelikelytobeimpactedbyclimatechange.
SomewhatIncrease.Highbaseflowsareimportantforthereproductionsuccessofblueheadsucker
(AndersonandStewart2007).MostpublishedresearchindicatesadeclineinrunoffintheUpper
ColoradoRiverBasinbythemid‐to‐late21stcentury(Rayetal.2008,Lukasetal.2014).
C2d)Dependenceonsnow‐coveredhabitats.Neutral
C3)Restrictiontouncommongeologicalfeaturesorderivatives.Neutral.
C4a)Dependenceonotherspeciestogeneratehabitat.Neutral
ClimateChangeVulnerabilityAssessmentforColoradoBLM253
C4b)Dietaryversatility.Neutral.Blueheadsuckerlarvaefeedondiatoms,zooplankton,and
dipteranlarvae(Carteretal.1986;MuthandSnyder1995;Ptaceketal.2005).Adultsandjuveniles
feedonmacroinvertebrates,algae,andinsectlarvae(Vanicek1967,Childsetal.1998,Osmundson
1999).
C4c)Pollinatorversatility(Plantsonly,notapplicable).
C4d)Dependenceonotherspeciesforpropaguledispersal.Neutral
C4e)Formspartofaninterspecificinteractionnotcoveredby4a‐d.Unknown
C5a)Measuredgeneticvariation.Increase.Althoughstudieshaveshownhighgeneticdiversityin
blueheadsuckeracrossthespeciesrange(Douglasetal.2009),hybridizationwiththenonnative
whitesuckercouldaffectthegeneticintegrityofthespecies.Hybridizationbetweenthenon‐native
whitesucker(Catostomuscommersoni)andblueheadsuckerhasbeendocumented,aswellas
individualswithgeneticcontributionsfromthewhitesucker,blueheadsucker,andnative
flannelmouthsucker(Catostomuslatipinnus)(McDonaldetal.2008).Thenon‐nativewhitesucker
hasfacilitatedintrogressionbetweentwonativespecies,andthereforethreatensthegenetic
integrityoftheblueheadandflannelmouthsuckers.Ageneticstudyofthespeciesrevealedthree
distinctgeographicareasthatareevolutionarilysignificantformaintainingthegeneticintegrityof
theblueheadsucker(referredtoasevolutionarilysignificantunits):theBonnevilleBasin,the
UpperLittleColoradoRiver,andtheColoradoRiver(Hopkenetal.2013).Allblueheadsucker
populationsinthestateofColoradobelongtotheColoradoRiverunit(Hopkenetal.2013).
C5b)Occurrenceofbottlenecksinrecentevolutionaryhistory.Unknown
C6)Phenologicalresponsetochangingseasonaltemperatureandprecipitationdynamics.
Unknown.
D1)Responsetorecentclimatechange.Unknown.
D2)Modeledfuturechangeinpopulationorrangesize.Unknown.
D3)Overlapofmodeledfuturerangewithcurrentrange.Unknown.
D4)Protectedareas.Unknown.
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Muth,R.T.andD.E.Snyder.1995.DietsofyoungColoradosquawfishandothersmallfishinbackwatersoftheGreen
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Osmundson,D.B.1999.LongitudinalvariationinfishcommunitystructureandwatertemperatureintheupperColorado
River:implicationsforColoradopikeminnowhabitatsuitability.FinalReportforRecoveryImplementationProgram,
ProjectNo.48.U.S.FishandWildlifeService,GrandJunction,CO.
Ptacek,J.A.,D.E.Rees,andW.J.Miller.2005.Blueheadsucker(Catostomusdiscobolus):atechnicalconservation
assessment.USDAForestService,RockyMountainRegion,FortCollins,Colorado.
Ray,A.J.,J.Barsugli,andK.Avery.2008.ClimateChangeinColorado:ASynthesistoSupportWaterResources
ManagementandAdaptation.ReporttotheColoradoWaterConservationBoard.
Rees,D.E.andW.J.Miller.2001.HabitatselectionandmovementofnativefishintheColoradoRiver,Colorado.Miller
EcologicalConsultants,Inc.,FortCollins,CO.
ClimateChangeVulnerabilityAssessmentforColoradoBLM255
Sigler,W.F.andJ.W.Sigler.1996.FishesofUtah;anaturalhistory.UniversityofUtahPress,SaltLakeCity,UT.
Smith,G.R.1966.DistributionandevolutionoftheNorthAmericanCatostomidfishesofSubgenusPantosteus,Genus
Catostomus.MiscellaneousPublicationsoftheMuseumofZoology,UniversityofMichigan,No.129.Universityof
Michigan,AnnArbor,MI.
Vanicek,C.D.1967.EcologicalstudiesofnativeGreenRiverfishesbelowFlamingGorgeDam,1964‐1966.Ph.D.Thesis,
UtahStateUniversity,Logan,UT.

256ColoradoNaturalHeritageProgram©2015
Bonytail Chub
Gilaelegans
G1/SX
ListedEndangered
Family:Cyprinidae
Nophotoavailable
Climate Vulnerability Rank: Extremely Vulnerable
ThisColoradostate‐widerankisbasedonthefollowingfactors:1)barrierstomovement;2)
potentialdeclineinrunoffandsubsequentdecreaseinflowsintheUpperColoradoRiverBasin;3)
relianceonrockysubstratesandgravelbarsforspawning;4)lackofvariabilityinannual
precipitationinlast50years;5)lackofgeneticvariation.
Distribution:ThebonytailchubisconsideredfunctionallyextinctinColorado(CarlsonandMuth
1989).NoverifiableoccurrencesofwildbonytailchubhavebeendocumentedinColoradosince
1984whenoneindividualwascaughtintheBlackRocksareanearGrandJunction,Colorado
(Kaedingetal.1986).Acaptivebroodstockwasestablishedfromsomeofthelastwildbonytail
collected,andstockingofcaptive‐rearedindividualsisaprimaryrecoverystrategy(Nesleretal.
2003).ThedistributionmapaboverepresentscriticalhabitatasdesignatedbyUSFWS(2003).
Habitat:Bonytailchubpreferbackwaterswithrockyormuddybottomsandflowingpools,but
reportssuggesttheycanalsooccurinstreamreacheswithswiftcurrents(USFWS2012).
EcologicalSystem:Streams
CCVI Scoring
B1)Exposuretosealevelrise.Neutral.
B2a)Distributionrelativetonaturalbarriers.Neutral/SomewhatIncrease.Naturalphysical
barrierstomovementintheColoradoRiveranditstributariesarenaturalrapidsandswift
ClimateChangeVulnerabilityAssessmentforColoradoBLM257
turbulentflows,andthesearelikelytofluctuatedependingonflows(U.S.FishandWildlifeService
2002).
B2b)Distributionrelativetoanthropogenicbarriers.Increase.Damsandimpoundmentsalong
theColoradoRiveranditstributariescreatebarriersforbonytailchubmovement,andaffect
seasonalavailabilityofhabitat(U.S.FishandWildlifeService2002).
B3)Impactoflandusechangesresultingfromhumanresponsestoclimatechange.Neutral.
C1)Dispersalandmovements.Decrease.Littleinformationisknownregardingthelifehistory
andmovementsofbonytailchub,butfishreleasedinNevadatraveledasmuchas56km(Marsh
andMueller1999).
C2ai)Predictedsensitivitytotemperature:historicalthermalniche.Neutral.Consideringthe
meanseasonaltemperaturevariationforoccupiedcells,thespecieshasexperiencedaverage(57.1‐
77°F/31.8‐43.0°C)temperaturevariationinthepast50years.
C2aii)Predictedsensitivitytotemperature:physiologicalthermalniche.Neutral.Thebonytail
chubisadaptedtothelarge,warm‐waterriversandstreamsoftheColoradoRiverBasin.Changes
tothermalhabitatshaveoccurredduetothein‐riverhypolimneticdamreleasesandthelossof
warm,floodplainwetlands(Kappenmanetal.2012).
C2bi)Predictedsensitivitytochangesinprecipitation,hydrology,ormoistureregime:
historicalhydrologicalniche.Increase.Consideringtherangeofmeanannualprecipitationacross
occupiedcells,thespecieshasexperiencedsmall(4‐10inches/100‐254mm)precipitation
variationinthepast50years.
C2bii)Predictedsensitivitytochangesinprecipitation,hydrology,ormoistureregime:
physiologicalhydrologicalniche.SomewhatIncrease.Maintenanceofstreamflowisimportant
fortherecoveryandconservationofbonytailchub,aspeciesnowconsideredfunctionallyextinctin
theUpperColoradoRiverSub‐basin(USFWS2012).Mostpublishedresearchindicatesadeclinein
runoffintheUpperColoradoRiverBasinbythemid‐to‐late21stcentury(Rayetal.2008,Lukaset
al.2014).
C2c)Dependenceonaspecificdisturbanceregimelikelytobeimpactedbyclimatechange.
Increase.Littleisknownaboutspawningrequirementsforbonytailchub,butitislikelythatlike
othermembersofthegenusGila,theyspawninrockysubstrates(USFWS2002).Pulsesinspring
flowsareimportantforcreatingcobblebarsaswellasforfloodingbottomlandthatserveas
nurseryhabitatforyoung(USFWS2002).Adequatebaseflowsarenecessaryforthecreationand
maintenanceofbonytailchubhabitat.Mostpublishedresearchindicatesadeclineinrunoffinthe
UpperColoradoRiverBasinbythemid‐to‐late21stcentury(Rayetal.2008,Lukasetal.2014),
whichcouldleadtofurtherlossanddegradationofhabitatforrazorbacksuckers.Increase.(USFWS
2002).
C2d)Dependenceonsnow‐coveredhabitats.Neutral.
258ColoradoNaturalHeritageProgram©2015
C3)Restrictiontouncommongeologicalfeaturesorderivatives.Increase.Rockysubstrates
andgravelbarsmaybeimportantspawninghabitatforbonytailchub(USFWS2002).Thecreation
andmaintenanceofthesehabitatsarejeopardizedbydamsandimpoundmentsthatalternatural
hydrologicregimes.
C4a)Dependenceonotherspeciestogeneratehabitat.Unknown.
C4b)Dietaryversatility.Neutral.Bonytailchubareomnivorous,andconsumeorganicmaterial,
aquaticmacrophytes,invertebrates,bullfrogs,andfish(Marshetal.2013).
C4c)Pollinatorversatility(Plantsonly,notapplicable).
C4d)Dependenceonotherspeciesforpropaguledispersal.Neutral.
C4e)Formspartofaninterspecificinteractionnotcoveredby4a‐d.Unknown.
C5a)Measuredgeneticvariation.Increase.Historicgeneticdiversityofthebonytailchubis
unknown,andsofewwildindividualsareleftthattheerosionofgeneticvariabilitymayhave
alreadyoccurred(USFWS2002).
C5b)Occurrenceofbottlenecksinrecentevolutionaryhistory.Unknown.
C6)Phenologicalresponsetochangingseasonaltemperatureandprecipitationdynamics.
Unknown.
D1)Responsetorecentclimatechange.Unknown.
D2)Modeledfuturechangeinpopulationorrangesize.Unknown.
D3)Overlapofmodeledfuturerangewithcurrentrange.Unknown.
D4)Protectedareas.Unknown.
Literature Cited
Carlson,C.A.,andR.T.Muth.1989.TheColoradoRiver:lifelineoftheAmericanSouthwest.CanadianSpecialPublication,
FisheriesandAquaticSciences106:220–239.Keppenman,K.M.,E.S.Cureton,J.Ilgen,M.Toner,W.C.Fraser,andG.A.
Kaeding,L.R.,B.D.Burdick,P.A.Schrader,andW.R.Noonan.1986.Recentcaptureofabonytail(Gilaelegans)and
observationsonthisnearlyextinctcyprinidfromtheColoradoRiver.Copeia4:1021‐1023.
Kappenman,K.M.,E.S.Cureton,J.Ilgen,M.Toner,W.C.Fraser,andG.A.Kindschi.2012.ThermalRequirementsofthe
Bonytail(Gilaelegans):ApplicationtoPropagationandThermal‐RegimeManagementofRiversoftheColoradoRiver
Basin.TheSouthwesternNaturalist57(4):421‐429.
Lukas,J.,J.Barsugli,N.Doesken,I.Rangwala,andK.Wolter.2014.ClimateChangeinColorado:ASynthesistoSupport
WaterResourcesManagementandAdaptation.AReportfortheColoradoWaterConservationBoard.WesternWater
Assessment.
ClimateChangeVulnerabilityAssessmentforColoradoBLM259
Marsh,P.C.,G.A.Mueller,andJ.D.Schooley.2013.SpringtimeFoodsofBonytail(Cyprinidae:Gilaelegans)InALower
ColoradoRiverBackwater.TheSouthwesternNaturalist,58(4):512‐516.
Marsh,P.C.andG.Mueller.1999.Spring‐summermovementsofBonytailinaColoradoRiverreservoir,LakeMohave,
ArizonaandNevada.U.S.GeologicalSurvey.Open‐FileReport99‐103.FortCollins,CO:U.S.GeologicalSurvey.42p.
Nesler,T.P.,K.Christopherson,J.M.Hudson,C.W.McAda,F.Pfeifer,andT.E.Czapla.2003.Anintegratedstockingplanfor
RazorbackSucker,Bonytail,andColoradoPikeminnowfortheUpperColoradoRiverendangeredfishrecoveryprogram.
Ray,A.J.,J.Barsugli,andK.Avery.2008.ClimateChangeinColorado:ASynthesistoSupportWaterResources
ManagementandAdaptation.ReporttotheColoradoWaterConservationBoard.
U.S.FishandWildlifeService.2002.Bonytail(Gilaelegans)RecoveryGoals:amendmentandsupplementtotheBonytail
ChubRecoveryPlan.U.S.FishandWildlifeService,Mountain‐PrairieRegion(6),Denver,Colorado.
U.S.FishandWildlifeService.2003.Bonytail(Gilaelegans)CriticalHabitatshapefile.U.S.FishandWildlifeService,
Mountain‐PrairieRegion(6),Denver,Colorado.Availableonlineathttps://catalog.data.gov/dataset/final‐critical‐habitat‐
for‐the‐bonytail‐chub‐gila‐elegans.
U.S.FishandWildlifeService.2012.Bonytail(Gilaelegans)5‐YearReview:SummaryandEvaluation.U.S.Fishand
WildlifeService,UpperColoradoRiverEndangeredFishRecoveryProgram.Denver,Colorado.July2012,29pp.

260ColoradoNaturalHeritageProgram©2015
Colorado Pikeminnow
Ptychocheiluslucius
G1/S1
ListedEndangered
Family:Cyprinidae
Climate Vulnerability Rank: Extremely Vulnerable
ThisColoradostate‐widerankisbasedonthefollowingfactors:1)barrierstomovement;2)
potentialdeclineinrunoffandsubsequentdecreaseinflowsintheUpperColoradoRiverBasin;3)
relianceongravel‐cobblesubstratesinhighgradientstreamsforspawning;4)lackofvariabilityin
annualprecipitationinlast50years;5)lackofgeneticvariation.
Distribution:TheColoradopikeminnownowoccursinapproximately1,090milesofriverhabitat
intheupperColoradoRiverBasinaboveLakePowellintheGreenRiver,upperColoradoRiver,and
SanJuanRiversub‐basins(USFWS2011).Thedistributionmapprovidedaboveisbasedoncritical
habitatdesignatedbyUSFWS(2013).Habitat:Coloradopikeminnowadultsarelong‐distance
migratorsthatrequireuninterruptedreachesofmediumtolargeriverswithpools,deeprunsand
eddyhabitatsmaintainedbyhighspringflows(USFWS2011).Gravelandcobbledepositsareused
forspawninghabitat;watertemperaturesduringspawningaretypically18to23˚C(USFWS2011).
EcologicalSystem:Streams
CCVI Scoring
B1)Exposuretosealevelrise.Neutral.
B2a)Distributionrelativetonaturalbarriers.Neutral/SomewhatIncrease.Historically,
Coloradopikeminnowmigratedlongdistancestoandfromspawningsites(Tyus1991).Rapidsand
ClimateChangeVulnerabilityAssessmentforColoradoBLM261
swiftturbulentflowscancreatenaturalbarrierstomovementofColoradopikeminnowduringhigh
flows,butthesebarriersarelikelyseasonal(USFWS2002).
B2b)Distributionrelativetoanthropogenicbarriers.Increase.Extensivedambuildinginthe
1930sthroughthe1960shasbeencitedastheprimarycausefortheextirpationofColorado
pikeminnowinthelowerColoradoRiverbasin(MuellerandMarsh2002,Osmundson2011).
AlthoughthespeciesstillpersistsintheupperColoradoRiverbasin,damshaveblockedupstream
passage,convertedfree‐flowingriverinesegmentsintolenticreservoirhabitat,andcooled
downstreamreacheswithhypolimneticreleases(Osmundson2011).
B3)Impactoflandusechangesresultingfromhumanresponsestoclimatechange.Neutral.
C1)Dispersalandmovements.Decrease.ColoradopikeminnowintheSanJuanRiverregularly
travelanaverageof4to62km(DurstandFranssen2014).
C2ai)Predictedsensitivitytotemperature:historicalthermalniche.Neutral.Consideringthe
meanseasonaltemperaturevariationforoccupiedcells,thespecieshasexperiencedaverage(57.1‐
77°F/31.8‐43.0°C)temperaturevariationinthepast50years.
C2aii)Predictedsensitivitytotemperature:physiologicalthermalniche.Somewhat
Increase/Neutral.Coloradopikeminnowevolvedinwarm‐waterriversandtributariesinthe
ColoradoRiverBasin.Evidencefromrecentstudiessuggestthatwarmerstreamtemperaturesin
theSanJuanRiverSub‐basincontributetofastergrowthandmaturityinColoradopikeminnowas
comparedtocolderstreamtemperaturesintheUpperColoradoRiverSub‐basin(Durstand
Franssen2014).Warmerstreamtemperaturesasaresultofclimatechangecouldresultinhigher
ratesofrecruitmentforColoradopikeminnow.
C2bi)Predictedsensitivitytochangesinprecipitation,hydrology,ormoistureregime:
historicalhydrologicalniche.SomewhatIncrease.Consideringtherangeofmeanannual
precipitationacrossoccupiedcells,thespecieshasexperiencedslightlylowerthanaverage(11‐20
inches/255‐508mm)precipitationvariationinthepast50years.
C2bii)Predictedsensitivitytochangesinprecipitation,hydrology,ormoistureregime:
physiologicalhydrologicalniche.SomewhatIncrease/Neutral.Coloradopikeminnowadults
requirepools,deepruns,andeddyhabitatsthatarecreatedandmaintainedbyhighspringflows.
Theseasonalhighflowscreatedbyspringrunoff“maintainchannelandhabitatdiversity,flush
sedimentsfromspawningareas,rejuvenatefoodproduction,formgravelandcobbledepositsused
forspawning,andrejuvenatebackwaternurseryhabitats”(USFWS2002).Mostpublishedresearch
indicatesadeclineinrunoffintheUpperColoradoRiverBasinbythemid‐to‐late21stcentury(Ray
etal.2008,Lukasetal.2014).Lowerflowscouldresultinafurtherdeclineinthecreationand
maintenanceofColoradopikeminnowhabitat.
C2c)Dependenceonaspecificdisturbanceregimelikelytobeimpactedbyclimatechange.
Increase.AdultColoradopikeminnowarepiscivorous.Historically,thespeciesreliedonnativeprey
fishesasamajorfoodsource.ThesenativefishesspawninMayandJuneduringhighspringflows.
Coloradopikeminnowpreyonthesmallyoungoftheyeargeneratedfromthesespawningevents,
262ColoradoNaturalHeritageProgram©2015
andspawnoncetheyarelargeenough(approx.50mmtotallength)intheearlytomid‐summer
(Nesleretal.1988,TyusandHaines1991,Franssenetal.2007).Climatemodelsprojectearlier
peaksinstreamflow,andthismayaltertheavailabilityofpreyfishforColoradopikeminnow.
Dependenceonsnow‐coveredhabitats.Neutral.
C3)Restrictiontouncommongeologicalfeaturesorderivatives.Increase.Colorado
pikeminnowspawningravel‐cobblesubstratesinhigh‐gradientstreams(Haynesetal.1984;Tyus
andHaines1991);backwatersformedinsilt‐sandbarsareconsideredidealnurseryhabitat
(Osmundsonetal.2002).DamsanddiversionsintheColoradoRiveranditstributarieshavealtered
naturalflowregimes,andlesshigh‐qualityhabitatisavailablefortheColoradopikeminnow.
C4a)Dependenceonotherspeciestogeneratehabitat.Neutral.
C4b)Dietaryversatility.Neutral.Coloradopikeminnowadultsarepiscivorousandarethemain
nativepredatoroftheColoradoRiverBasinbecauseoftheirlargesizeandlargemouth(Vanicek
andKramer1969,Minckley1973,HoldenandWick1982,USFWS2002).YoungColorado
pikeminnowconsumeinsects,copepods,cladocerans,andmidgelarvae(Vanicek1967,Jacobiand
Jacobi1982,MuthandSnyder1995,USFWS2002).
C4c)Pollinatorversatility(Plantsonly,notapplicable).
C4d)Dependenceonotherspeciesforpropaguledispersal.Neutral.
C4e)Formspartofaninterspecificinteractionnotcoveredby4a‐d.Unknown.
C5a)Measuredgeneticvariation.Increase.GeneticdiversitystudiesofmitochondrialDNAin
hatcherystockandmuseumspecimenshasrevealedlowgeneticdiversityinColoradopikeminnow
(BorleyandWhite2006).
C5b)Occurrenceofbottlenecksinrecentevolutionaryhistory.SomewhatIncrease.Apost‐
Pleistocenegeneticbottleneckhasbeenproposedasthecauseoflowlevelsofgeneticvariationin
Coloradopikeminnow(BorleyandWhite2006).
C6)Phenologicalresponsetochangingseasonaltemperatureandprecipitationdynamics.
Unknown.
D1)Responsetorecentclimatechange.Unknown.
D2)Modeledfuturechangeinpopulationorrangesize.Unknown.
D3)Overlapofmodeledfuturerangewithcurrentrange.Unknown.
D4)Protectedareas.Unknown.
ClimateChangeVulnerabilityAssessmentforColoradoBLM263
Literature Cited
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amonghatcherystocksandhistoricspecimens.NorthAmericanJournalofFisheriesManagement26(4):916‐920.
Durst,S.L.andN.R.Franssen.2014.MovementandgrowthofjuvenileColoradoPikeminnows(Ptychocheiluslucius)inthe
SanJuanRiver,NMandUT.TransactionsoftheAmericanFisheriesSociety143:519–527.
Franssen,N.R.,K.B.Gido,andD.L.Propst.2007.Flowregimeaffectsavailabilityofnativeandnonnativepreyofan
endangeredpredator.BiologicalConservation138:330–340.
Haynes,C.M.,T.A.Lytle,E.J.Wick,andR.T.Muth.1984.LarvalColoradosquawfish(Ptychocheiluslucius)intheUpper
ColoradoRiverbasin,Colorado,1979‐1981.TheSouthwesternNaturalist29:21‐33.
Holden,P.B.andE.J.Wick.1982.LifehistoryandprospectsforrecoveryofColoradosquawfish.In:W.H.Miller(ed.),
FishesoftheUpperColoradoRiverSystem:presentandfuture,pp.98‐108.AmericanFisheriesSociety.
Jacobi,G.Z.,andM.D.Jacobi.1982.Fishstomachcontentanalysis.Pages285‐324inColoradoRiverfisheryprojectfinal
report.Part3,Contractedstudies.U.S.FishandWildlifeServiceandBureauofReclamation,SaltLakeCity,UT.
Minckley,W.L1973.FishesofArizona.ArizonaGameandFishDepartment,Phoenix.pp.158‐159.
Mueller,G.A.andP.C.Marsh.2002.Lost,adesertriveranditsnativefishes:ahistoricalperspectiveoftheLowerColorado
River.InformationandTechnologyReportUSBS/BRD/ITR‐2002‐0010,U.S.GovernmentPrintingOffice,Denver,CO.69
pp.
Muth,R.T.andD.E.Snyder.1995.DietsofyoungColoradosquawfishandothersmallfishinbackwatersoftheGreen
River,ColoradoandUtah.TheGreatBasinNaturalist55:95–104.
NeslerT.P.,R.T.Muth,andA.F.Wasowicz1988.EvidenceforbaselineflowspikesasspawningcuesforColorado
SquawfishintheYampaRiver,Colorado.AmericanFisheriesSocietySymposium5:68‐79.
Osmundson,D.B.,R..Ryel,V.L.LamarraandJ.Pitlick.2002.Flowsediment‐biotarelations:implicationsforriver
regulationeffectsonnativefishabundance.EcologicalApplications12:1719‐1739.
Osmundson,D.B.2011.ThermalRegimeSuitability:AssessmentofUpstreamRangeRestorationPotentialforColorado
Pikeminnow,AWarmwaterEndangeredFish.RiverRestorationApplications27:706‐722.
Tyus,H.M.1991.EcologyandmanagementofColoradosquawfish.Pages379–402inW.L.MinckleyandJ.E.Deacon(eds.).
Battleagainstextinction:nativefishmanagementintheAmericanwest.TheUniversityofArizonaPress,Tucson.
Tyus,H.M.,andGB.Haines.1991.Distribution,habitatuse,andgrowthofage‐OColoradosquawfishintheGreenRiver
basin,ColoradoandUtah.TransactionsoftheAmericanFisheriesSociety120:79‐89.
U.S.FishandWildlifeService[USFWS].2002.Coloradopikeminnow(Ptychocheiluslucius)RecoveryGoals:amendment
andsupplementtotheColoradoSquawfishRecoveryPlan.U.S.FishandWildlifeService,Mountain‐PrairieRegion(6),
Denver,Colorado.
U.S.FishandWildlifeService[USFWS].2011.Coloradopikeminnow(Ptychocheiluslucius)5‐yearreview:summaryand
evaluation.USFWS,UpperColoradoRiverEndangeredFishRecoveryProgram,Denver,Colorado.
U.S.FishandWildlifeService[USFWS].2013.Coloradopikeminnow(Ptychocheiluslucius)CriticalHabitatshapefile.U.S.
FishandWildlifeService,Mountain‐PrairieRegion(6),Denver,Colorado.Availableonlineat
https://catalog.data.gov/dataset/final‐critical‐habitat‐for‐the‐colorado‐pikeminnow‐ptychocheilus‐lucius
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Vanicek,C.D.1967.EcologicalstudiesofnativeGreenRiverfishesbelowFlamingGorgeDam,1964–1966.Unpublished
Ph.D.dissertation,UtahStateUniversity,Logan.i0038‐4909‐49‐2‐203‐Vanicek1
Vanicek,C.D.,andR.Kramer.1969.LifehistoryoftheColoradosquawfish,Ptychocheiluslucius,andtheColoradochub,
Gilarobusta,intheGreenRiverinDinosaurNationalMonument1964–1966.TransactionsoftheAmericanFisheries
Society98:193–208.

ClimateChangeVulnerabilityAssessmentforColoradoBLM265
Colorado River Cutthroat Trout
Oncorhynchusclarkiipleuriticus
G4T3/S3
Family:Salmonidae
Climate Vulnerability Rank: Extremely Vulnerable
ThisColoradostate‐widerankisbasedonthefollowingfactors:1)barrierstomovement;2)
potentialcomplexeffectsofwarmingstreamtemperaturesthatmayincreaseColoradoRiver
cutthroattrout(CRCThereafter)recruitment,aswellasprovidemoresuitablehabitatfor
nonnativesalmonidsthathybridizeandcompetewithCRCT;3)relianceongravelbarsfor
spawning;4)lackofvariabilityinannualprecipitationinlast50years;5)rainbowtroutandother
subspeciesofcutthroattrouthybridizewithCRCTandcouldthreatenthegeneticintegrityofCRCT.
Distribution:ColoradoRivercutthroattroutarefoundinthefollowingriverbasinsofColorado:
Dolores,Gunnison,UpperGreen,UpperColorado,Yampa,White,andSanJuan(Hirschetal.2013).
Recentgeneticandmeristicstudieshaveidentifiedtwoextantcutthroatlineageswithinthisrange,
provisionallydesignatedtheBlueLineage,nativetotheYampa,GreenandWhiteRiverBasins,and
theGreenLineage,nativetotheUpperColorado,GunnisonandDoloresbasins(Metcalfetal.2012,
Bestgenetal.2013,USFWS2014).AthirdlineagenativetotheSanJuanbasinisevidentlyextinct,
thoughblueandgreenlineagepopulationshavebeenestablishedinthisbasinbystocking.In
keepingwithcurrently‐recognizedinlandcutthroattaxonomy,thisassessmentconsidersall
cutthroatsindigenoustotheWestSlopeasCRCT.Habitat:InColorado,CRCTrequirecool,clear
waterinstreamswithwell‐vegetated,stablebanks;deeppools,boulders,andlogsareimportant
forprovidingcoverforCRCT(Young1995,Youngetal.1998).CRCTalsooccurinlakes,butthese
arerelativelyrare(Hirshetal.2013).Elevation:CRCToccursfrom4,600fttonearly12,500ft
acrossitsrange(Hirshetal.2013).SpecificelevationrangesforColoradoarenotavailable.
EcologicalSystem:MontaneStreams
266ColoradoNaturalHeritageProgram©2015
CCVI Scoring
B1)Exposuretosealevelrise.Neutral.
B2a)Distributionrelativetonaturalbarriers.Neutral/SomewhatIncrease.Waterfalls,beaver
dams,bedrock,debrisandrapidsarenaturalfeaturesintheriverbasinsthatprovidehabitatfor
CRCT(Hirshetal.2013).Manyofthesefeaturesmayonlyappearduringhighflows.Nonetheless,
theymaycreateseasonalbarrierstomovementforCRCT.
B2b)Distributionrelativetoanthropogenicbarriers.Neutral/SomewhatIncrease.Theeffectof
barrierscanbecomplexforCRCT.Thepresenceofabarriercanblocktheupstreammovementof
nonnativesalmonidsthatnegativelyaffectpopulationsofCRCTthroughhybridization,foodand
spacecompetition,andpredation(AllendorfandLeary1988,ForbesandAllendorf1991,Hirshet
al.2013).DamsandimpoundmentsintheColoradoRiverBasinanditstributariescreatebarriers
toCRCTmovement(Young2008).
B3)Impactoflandusechangesresultingfromhumanresponsestoclimatechange.Neutral.
C1)Dispersalandmovements.SomewhatDecrease.EvidencefromYoung(1995)suggeststhat
summerhomerangesforCRCTrangefrom11to652meters.
C2ai)Predictedsensitivitytotemperature:historicalthermalniche.Neutral.Consideringthe
meanseasonaltemperaturevariationforoccupiedcells,thespecieshasexperiencedaverage(57.1‐
77°F/31.8‐43.0°C)temperaturevariationinthepast50years.
C2aii)Predictedsensitivitytotemperature:physiologicalthermalniche.Somewhat
Increase/Neutral.ClimatewarmingmayhavecomplexeffectsonCRCTpopulations.ManyCRCT
populationspersistinhigherelevationstreamsbecauseunlikenonnativesalmonids,theycan
toleratecolderwatertemperatures.However,thesecoldtemperaturesmaynotprovideconditions
thatCRCTcanthrivein,andgrowthandrecruitmentmaybehinderedbytheselowtemperatures.
HigherelevationstreamsthatarecurrentlytoocoldtosustainCRCTpopulationsmaywarmenough
inthefuturetoprovidesuitablehabitatforCRCT.Warmerstreamtempscouldresultinearly
spawningandhigheroverwintersurvivalforCRCT.Itisalsopossiblethatthesewarmerstream
temperatureswillprovidesuitablehabitatfornonnativefishaswell.
C2bi)Predictedsensitivitytochangesinprecipitation,hydrology,ormoistureregime:
historicalhydrologicalniche.SomewhatIncrease.Consideringtherangeofmeanannual
precipitationacrossoccupiedcells,thespecieshasexperiencedslightlylowerthanaverage(11‐20
inches/255‐508mm)precipitationvariationinthepast50years.
C2bii)Predictedsensitivitytochangesinprecipitation,hydrology,ormoistureregime:
physiologicalhydrologicalniche.Increase.Lackofinstreamflowsduetodroughtconditionsis
consideredthehighestclimatechangeriskfactorforCRCT(Haaketal.2010).
C2c)Dependenceonaspecificdisturbanceregimelikelytobeimpactedbyclimatechange.
Neutral/SomewhatIncrease.SpawningofCRCTbeginsafterrunoffhaspeakedinspringorearly
ClimateChangeVulnerabilityAssessmentforColoradoBLM267
summer(Young1995).Watertemperaturesmayalsoprovidespawningcues(Young1995).
Temperatureincreasesduetoclimatechangemayleadtoearlierpeakrunoffandwarmerwater
temperatures.ThesemayresultinearlierspawningandhigheroverwintersurvivalforCRCT.
FemaleCRCTdepositeggs10‐25cmdeepinspawninggravel.Naturalhydrologicregimesthathelp
creategravelbarshavebeenalteredbydam‐relatedchangesintimingandflowlevels.Most
publishedresearchindicatesadeclineinrunoffintheUpperColoradoRiverBasinbythemid‐to‐
late21stcentury(Rayetal.2008,Lukasetal.2014),whichcouldleadtofurtherlackofhydrologic
processesrequiredtocreateandmaintainhabitatforCRCT.
C2d)Dependenceonsnow‐coveredhabitats.Neutral.
C3)Restrictiontouncommongeologicalfeaturesorderivatives.Neutral/SomewhatIncrease.
Requiresgravelsforspawning,seeaboveexplanationinC2C.
C4)Relianceoninterspecificinteractions.Neutral.
C4a)Dependenceonotherspeciestogeneratehabitat.Neutral.
C4b)Dietaryversatility.Neutral.Amphipods,plankton,dipterans,andhymenopteransareall
importantcomponentsofCRCTdiet(Colburn1966,Bozeketal.1994).
C4c)Pollinatorversatility(Plantsonly,notapplicable).
C4d)Dependenceonotherspeciesforpropaguledispersal.Neutral.
C4e)Formspartofaninterspecificinteractionnotcoveredby4a‐d.Unknown.
C5a)Measuredgeneticvariation.Increase.Nonnativerainbowtrout(Oncorhynchusmykiss)and
othersubspeciesofcutthroattrout(Oncorhynchusclarkiispp.)havehybridizedwithCRCT,thus
reducingthegeneticintegrityofthesubspecies(AllendorfandLeary1988,ForbesandAllendorf
1991,CRCTConservationTeam2006;Hirschetal.2013).Naturalorconstructedbarriersexistto
limitgeneticmixingofrainbowandothersubspeciesofcutthroattroutandCRCT.However,these
barriersalsoposeathreattoCRCTasitrestrictsindividualstoshort,headwaterstreamsegments
(Young2008).Thisrestrictionrenderspopulationsmorevulnerabletoextirpationfromstochastic
events,andcouldresultinthelongtermlossofgeneticvariability(Young2008,Robertsetal.
2013).
C5b)Occurrenceofbottlenecksinrecentevolutionaryhistory.Unknown.
C6)Phenologicalresponsetochangingseasonaltemperatureandprecipitationdynamics.
Unknown.
D1)Responsetorecentclimatechange.Unknown.
D2)Modeledfuturechangeinpopulationorrangesize.Unknown.
D3)Overlapofmodeledfuturerangewithcurrentrange.Unknown.
268ColoradoNaturalHeritageProgram©2015
D4)Protectedareas.Unknown.
Literature Cited
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Parks,Denver,Colorado.FisheriesResearchDivisionSpecialReport9
Coleman,M.A.andK.D.Fausch.2007.Coldsummertemperaturelimitsrecruitmentofage‐0cutthroattroutinhigh‐
elevationColoradostreams.TransactionsoftheAmericanFisheriesSociety136:1231‐1244.
CRCTConservationTeam.2006.ConservationagreementforColoradoRivercutthroattrout(Oncorhynchusclarkii
pleuriticus)intheStatesofColorado,Utah,andWyoming.ColoradoDivisionofWildlife,FortCollins.10p.
Forbes,S.H.andF.W.Allendorf.1991.Mitochondrialgenotypeshavenodetectableeffectsonmeristictraitsincutthroat
trouthybridswarms.Evolution45:1350‐1359.
Haak,A.L.,J.E.Williams,D.Isaak,A.Todd,C.Muhlfeld,J.L.Kershner,R.Gresswell,S.Hostetler,andH.M.Neville.2010.The
potentialinfluenceofchangingclimateonthepersistenceofsalmonidsoftheinlandwest.U.S.GeologicalSurvey,Open‐
FileReport2010‐1236,Reston,Virginia.AccessedNov13,2014.Onlineat:pubs.usgs.gov/of/2010/1236/.
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pleuriticus):2010.ColoradoRiverCutthroatTroutConservationTeamReport.ColoradoParksandWildlife,FortCollins.
Lukas,J.,J.Barsugli,N.Doesken,I.Rangwala,andK.Wolter.2014.ClimateChangeinColorado:ASynthesistoSupport
WaterResourcesManagementandAdaptation.AReportfortheColoradoWaterConservationBoard.WesternWater
Assessment.
Metcalf,J.L.,S.S.Stowell,C.M.Kennedy,K.B.Rogers,D.McDonald,J.Epp,K.Keepers,A.Cooper,J.J.Austin,andA.P.Martin.
2012.Historicalstockingdataand19thcenturyDNArevealhuman‐inducedchangestonativediversityanddistribution
ofcutthroattrout.MolecularEcology21:5194‐5207.
Ray,A.J.,J.Barsugli,andK.Avery.2008.ClimateChangeinColorado:ASynthesistoSupportWaterResources
ManagementandAdaptation.ReporttotheColoradoWaterConservationBoard.
Roberts,J.J.,K.D.Fausch,D.P.Peterson,andM.B.Hooten.2013.Fragmentationandthermalrisksfromclimatechange
interacttoaffectpersistenceofnativetroutintheColoradoRiverbasin.GlobalChangeBiology19:1383‐1398.
U.S.FishandWildlifeService[USFWS].2014.FinalSummaryReport:GreenbackCutthroatTroutGeneticsandMeristics
StudiesFacilitatedExpertPanelWorkshop.USFWSRegion6,Lakewood,CO,OrderNo.F13PB00113.AccessedNov6,
2014.Available:
http://cpw.state.co.us/Documents/Research/Aquatic/CutthroatTrout/2014GreenbackCutthroatTroutWorkshopSummar
y.pdf.
ClimateChangeVulnerabilityAssessmentforColoradoBLM269
Young,M.K.1995.ColoradoRivercutthroattrout.M.K.Youngtechnicaleditor.Pages16‐23.In:AConservation
AssessmentforInlandCutthroatTrout.USDAForestService,RockyMountainForestandRangeExperimentStation,Fort
Collins,Colorado.GeneralTechnicalReport.RM‐GTR‐256.
Young,M.K.,K.A.Meyer,D.J.Isaak,andR.A.Wilkison.1998.Habitatselectionandmovementbyindividualcutthroattrout
intheabsenceofcompetitors.JournalofFreshwaterEcology13:371‐381.
Young,M.K.2008.ColoradoRiverCutthroatTrout:ATechnicalConservationAssessment.USDAForestService,Rocky
MountainStation,FortCollins,CO.

270ColoradoNaturalHeritageProgram©2015
Flannelmouth Sucker
Catostomuslatipinnis
G3G4/S3
Family:Catostomidae
Climate Vulnerability Rank: Highly Vulnerable
ThisColoradostate‐widerankisbasedonthefollowingfactors:1)barrierstomovement;2)
potentialdeclineinrunoffandsubsequentdecreaseinflowsintheUpperColoradoRiverBasin;3)
relianceongravelbarsforspawning;4)lackofgeneticvariation.
Distribution:InColorado,theflannelmouthsuckerisfoundthroughouttheUpperColoradoRiver
drainage.Habitat:InColorado,flannelmouthsuckerresideinmainstemandtributarystreamsin
theUpperColoradoRiverBasin.Theyareopportunisticbenthicfeeders.Adultsoccupydeepriffles
andrunsaswellasdeep,murkypoolswithsparsevegetation(McAda1977;SiglerandSigler1996;
BezzeridesandBestgen2002),whileyoungfisharetypicallyfoundinquiet,shallowrifflesand
near‐shoreeddies(Childsetal.1998).
EcologicalSystem:Streams
CCVI Scoring
B1)Exposuretosealevelrise.Neutral.
B2a)Distributionrelativetonaturalbarriers.Increase.Flannelmouthsuckeraremost
commonlyfoundinpoolsanddeeperrunsofthemainstemandtributariesoftheColoradoRiver
withinthestateofColorado(BezzeridesandBestgen2002;SiglerandMiller1963;Minckleyand
Holden1980).
ClimateChangeVulnerabilityAssessmentforColoradoBLM271
B2b)Distributionrelativetoanthropogenicbarriers.Increase.Damsandimpoundmentsalong
theColoradoRiveranditstributariescreatebarriersforflannelmouthsuckermovement.This
speciesdoesnotdowellinimpoundments(McAda1977,SiglerandSigler1996,Bezzeridesand
Bestgen2002).
B3)Impactoflandusechangesresultingfromhumanresponsestoclimatechange.Neutral.
C1)Dispersalandmovements.Decrease.Flannelmouthsuckerarecapableoflongdistance
movementsasfaras229kilometers(Weiss1993).
C2ai)Predictedsensitivitytotemperature:historicalthermalniche.Neutral.Consideringthe
meanseasonaltemperaturevariationforoccupiedcells,thespecieshasexperiencedaverage(57.1‐
77°F/31.8‐43.0°C)temperaturevariationinthepast50years.
C2aii)Predictedsensitivitytotemperature:physiologicalthermalniche.Neutral/Somewhat
Increase.Flannelmouthsuckeroccupywarmandcoolwaterreachesofmostmainstemriversand
largetributariesinalltheColoradoRiverBasinsystemsinColoradoincludingthoseintheSanJuan,
Dolores,Gunnison,Colorado,White,Yampa(includingtheLittleSnakeRiver),andGreenRiver
basins(BestgenandZelasko2004;ColoradoParksandWildlife2015).
C2bi)Predictedsensitivitytochangesinprecipitation,hydrology,ormoistureregime:
historicalhydrologicalniche.SomewhatDecrease.Consideringtherangeofmeanannual
precipitationacrossoccupiedcells,thespecieshasexperiencedgreaterthanaverage(>40
inches/1,016mm)precipitationvariationinthepast50years.
C2bii)Predictedsensitivitytochangesinprecipitation,hydrology,ormoistureregime:
physiologicalhydrologicalniche.SomewhatIncrease.Highbaseflowsareimportantforthe
reproductionsuccessofflannelmouthsucker,aswellasblueheadandrazorbacksuckers(Anderson
andStewart2007).MostpublishedresearchindicatesadeclineinrunoffintheUpperColorado
RiverBasinbythemid‐to‐late21stcentury(Lukasetal.2014;Rayetal.2008).Reducedbaseflows
maybeassociatedwithincreasesinthenon‐nativewhitesucker(C.commersonii)populations.
Hybridizationofflannelmouthsuckerandwhitesuckerisaveryseriousthreattoflannelmouth
suckerintheColoradoRiverBasin(AndersonandStewart2007).
C2c)Dependenceonaspecificdisturbanceregimelikelytobeimpactedbyclimatechange.
Neutral.ThisspeciesevolvedintheColoradoRiverBasinandisadaptedtohighspringrunoff(Rees
etal.2005).SpringflowsfortheColoradoRiverareprojectedtopeakearlierandbehigherin2035‐
2064(Lukasetal.2014).
C2d)Dependenceonsnow‐coveredhabitats.Neutral.
C3)Restrictiontouncommongeologicalfeaturesorderivatives.Neutral/SomewhatIncrease.
Femalesspawnovergravel(CPW2014).Hydrologicprocessesthathelpcreateandmaintaingravel
barsmaybealteredduettoprojecteddecreasesinflowsintheColoradoRiverBasin(Lukasetal.
2014;Rayetal.2008).
272ColoradoNaturalHeritageProgram©2015
C4a)Dependenceonotherspeciestogeneratehabitat.Unknown.
C4b)Dietaryversatility.Neutral.
C4c)Pollinatorversatility(Plantsonly,notapplicable).
C4d)Dependenceonotherspeciesforpropaguledispersal.Neutral.
C4e)Formspartofaninterspecificinteractionnotcoveredby4a‐d.Unknown.
C5a)Measuredgeneticvariation.Increase.Althoughthespeciesiswidespreadthroughoutthe
ColoradoRiverBasin,arecentstudyfoundverylowlevelsofgeneticdiversitybasin‐wide(Douglas
andDouglas2003).Furthermore,hybridsbetweennonnativewhitesucker(Catostomus
commersoni)andflannelmouthsuckerhavebeendocumentedintheColorado,Gunnison,and
Yamparivers(AndersonandStewart2007;DouglasandDouglas2003;Shiozawaetal.2003).
Hybridizationbetweenthenon‐nativewhitesuckerandthenativeblueheadsuckerhasalsobeen
documented,aswellasindividualswithgeneticcontributionsfromthewhitesucker,bluehead
sucker,andnativeflannelmouthsucker(Catostomuslatipinnus)(McDonaldetal.2008).Thenon‐
nativewhitesuckerhasfacilitatedintrogressionbetweentwonativespecies,andtherefore
threatensthegeneticintegrityoftheblueheadandflannelmouthsuckers.Whitesuckershave
becomepervasivethroughouttheColoradoRiverBasin,hybridizingreadilywithflannelmouth
suckers,thuscreatingaseriousextinctionrisktoflannelmouthsuckers(McDonaldetal.2008).
C5b)Occurrenceofbottlenecksinrecentevolutionaryhistory.Unknown.
C6)Phenologicalresponsetochangingseasonaltemperatureandprecipitationdynamics.
Unknown.
D1)Responsetorecentclimatechange.Unknown.
D2)Modeledfuturechangeinpopulationorrangesize.Unknown.
D3)Overlapofmodeledfuturerangewithcurrentrange.Unknown.
D4)Protectedareas.Unknown.
Literature Cited
Anderson,R.M.andG.Stewart.2007.Fish‐FlowInvestigation:II.Impactsofstreamflowalterationsonthenativefish
assemblageandtheirhabitatavailabilityasdeterminedby2Dmodelingandtheuseoffishpopulationdatatosupport
instreamflowrecommendationsforthesectionsoftheYampa,Colorado,GunnisonandDoloresRiversinColorado.
ColoradoDivisionofWildlifeSpecialReportNo.80,DOW‐R‐S‐80‐07.FortCollins.
Bestgen,K.R.,andK.A.Zelasko.2004.DistributionandstatusofnativefishesintheColoradoRiverBasin,Colorado.Final
ReporttoColoradoDivisionofWildlife.FortCollins,CO
Bezzerides,N.,andK.R.Bestgen.2002.StatusReviewofRoundtailChubGilarobusta,FlannelmouthSuckerCatostomus
latipinnis,andBlueheadSuckerCatostomusdiscobolusintheColoradoRiverBasin.Finalreport.SubmittedtoU.S.
ClimateChangeVulnerabilityAssessmentforColoradoBLM273
DepartmentoftheInterior,BureauofReclamation,SaltLakeCity,Utah.LarvalFishLaboratoryContribution118,
ColoradoStateUniversity,Ft.Collins.
Childs,M.R.,R.W.Clarkson,andA.T.Robinson.1998.ResourceusebylarvalandearlyjuvenilenativefishesintheLittle
ColoradoRiver,GrandCanyon,Arizona.TransactionsoftheAmericanFisheriesSociety127:620‐629.
ColoradoParksandWildlife.2015.StateofColoradoConservationandManagementPlanfortheRoundtailChub(Gilia
robusta),BlueheadSucker(Catostomusdiscobolus)andFlannelmouthSucker(Catostomuslatipinnis).UnpublishedDraft.
Douglas,M.R.andM.E.Douglas.2003.YampaRiverhybridsuckergeneticassessment.DepartmentofFisheryandWildlife
Biology,ColoradoStateUniversity,FortCollins,CO.
Lukas,J.,J.Barsugli,N.Doesken,I.Rangwala,andK.Wolter.2014.ClimateChangeinColorado:ASynthesistoSupport
WaterResourcesManagementandAdaptation.AReportfortheColoradoWaterConservationBoard.WesternWater
Assessment.
McAda,C.W.1977.AspectsofthelifehistoryofthreeCatostomidsnativetotheUpperColoradoRiverBasin.Master’s
thesis,UtahStateUniversity,Logan,Utah.
Minckley,W.L.andP.B.Holden.1980.BlueheadsuckerinD.S.Lee,C.R.Gilbert,C.H.Hocutt,R.E.Jenkins,D.E.MacAllister
andJ.R.Stauffer,Jr.,editors.AtlasofNorthAmericanfreshwaterfishes.NorthCarolinaStateMuseumofNaturalHistory,
Columbia.p.377.
Ray,A.J.,J.Barsugli,andK.Avery.2008.ClimateChangeinColorado:ASynthesistoSupportWaterResources
ManagementandAdaptation.ReporttotheColoradoWaterConservationBoard.
Rees,D.E.,J.A.Ptacek,R.J.Carr,andW.J.Miller.2005.FlannelmouthSucker(Catostomuslatipinnis):atechnical
conservationassessment.[Online].USDAForestService,RockyMountainRegion.Available:
http://www.fs.fed.us/r2/projects/scp/assessments/flannelmouthsucker.pdf[Jan8,2015].
Sigler,W.F.andR.R.Miller.1963.FishesofUtah.UtahDepartmentofGameandFish,SaltLakeCity,UT.
Sigler,W.F.andJ.W.Sigler.1996.FishesofUtah;anaturalhistory.UniversityofUtahPress,SaltLakeCity,UT.
Weiss,S.J.1993.Spawning,movementandpopulationstructureofflannelmouthsuckerinthePariaRiver.M.S.Thesis.
UniversityofArizona,Tucson,AZ.

274ColoradoNaturalHeritageProgram©2015
Humpback Chub
Gilacypha
G1/S1
ListedEndangered
Family:Cyprinidae
Nophotoavailable
Climate Vulnerability Rank: Extremely Vulnerable
ThisColoradostate‐widerankisbasedonthefollowingfactors:1)barrierstomovement;2)
potentialdeclineinrunoffandsubsequentdecreaseinflowsintheUpperColoradoRiverBasin;3)
relianceongravelbarsforspawning;4)lackofgeneticvariation.
Distribution:OnlytwohumpbackchubpopulationsstillexistinColorado:theYampaCanyon
populationontheYampaRiverandtheBlackRockspopulationontheColoradoRiver(U.S.Fishand
WildlifeService2002).Thedistributionmapaboveshowscriticalhabitatasdesignatedbythe
USFWS(2003).Habitat:InColorado,adulthumpbackchubresideinswift,turbulenthabitatsand
indeeppoolsincanyons(Kaedingetal.1990;Leeetal.1981).Theyarealsofoundinwhitewaterin
deepeddies(Minckley1991).Juvenilesaregenerallyfoundinmoreshallowareas;youngofthe
yearhavebeendocumentedinshallowareasnearshorewithslowcurrentsandfinecobblesand
boulders(GormanandSeales1995).
EcologicalSystem:Streams
CCVI Scoring
B1)Exposuretosealevelrise.Neutral.
B2a)Distributionrelativetonaturalbarriers.Neutral/SomewhatIncrease.Rapidsand
waterfallsmaycreatenaturalbarriersintheColorado,Yampa,andGreenrivers.
ClimateChangeVulnerabilityAssessmentforColoradoBLM275
B2b)Distributionrelativetoanthropogenicbarriers.Increase.Damsanddiversionsinthe
ColoradoRiveranditstributariescreatebarrierstohumpbackchubmovement,andcausechanges
inchannelgeomorphology,sedimentregimes,andstreamflows(U.S.FishandWildlifeService
2011).
B3)Impactoflandusechangesresultingfromhumanresponsestoclimatechange.Neutral.
C1)Dispersalandmovements.Neutral/SomewhatDecrease.Althoughmanybigriverfishfrom
theColoradoRiverBasintravellongdistances,thehumpbackchubhasbeenreportedtohave
relativelylimitedmovement(Paukertetal.2006).Theaveragespawningdistancesforhumpback
chubintheBlackRocksareaoftheColoradoRiverhasbeenreportedas6.4km(ValdezandRyel
1995).
C2ai)Predictedsensitivitytotemperature:historicalthermalniche.Neutral.Consideringthe
meanseasonaltemperaturevariationforoccupiedcells,thespecieshasexperiencedaverage(57.1‐
77°F/31.8‐43.0°C)temperaturevariationinthepast50years.
C2aii)Predictedsensitivitytotemperature:physiologicalthermalniche.Neutral/Somewhat
Increase.Thehumpbackchubisadaptedtothelarge,warm‐waterriversandstreamsofthe
ColoradoRiverBasin.Humpbackchubgrowrelativelyquicklyinwarmwatertemperatures,and
coldertemperaturessuchasthosecausedbyhypolimneticdamreleaseshavebeenshownto
significantlylowergrowthrates(ClarksonandChilds2000).Warmerwatertemperaturescaused
byprojectedincreasesintemperaturemayhelpincreaserecruitmentratesinhumpbackchub
populations.
C2bi)Predictedsensitivitytochangesinprecipitation,hydrology,ormoistureregime:
historicalhydrologicalniche.Increase.Consideringtherangeofmeanannualprecipitationacross
occupiedcells,thespecieshasexperiencedsmall(4‐10inches/100‐254mm)precipitation
variationinthepast50years.
C2bii)Predictedsensitivitytochangesinprecipitation,hydrology,ormoistureregime:
physiologicalhydrologicalniche.SomewhatIncrease.Maintenanceofstreamflowisimportant
fortherecoveryandconservationofbonytailchub(U.S.FishandWildlifeService2011).Flow
recommendationshavebeendevelopedforhumpbackchubintheGreenRiver(Muthetal.2000),
YampaRiver(Moddeetal.1999),andupperColoradoRiver(McAda2003).However,theremaybe
lesswateravailableinfuturetoprovidetheseflows.Mostpublishedresearchindicatesadeclinein
runoffintheUpperColoradoRiverBasinbythemid‐to‐late21stcentury(Lukasetal.2014;Jayet
al.2008).
C2c)Dependenceonaspecificdisturbanceregimelikelytobeimpactedbyclimatechange.
Increase.Highspringflowsthatcreateandcleangravelbars,aswellastemporarilyreducenon‐
nativefishpopulations,arepositivelyassociatedwithreproductionofhumpbackchubintheLower
ColoradoRiver(Gorman1994).
C2d)Dependenceonsnow‐coveredhabitats.Neutral.
276ColoradoNaturalHeritageProgram©2015
C3)Restrictiontouncommongeologicalfeaturesorderivatives.Increase.Humpbackchubare
associatedwithcleangravelbarsforspawning(Gorman1994;U.S.FishandWildlifeService2002).
C4a)Dependenceonotherspeciestogeneratehabitat.Neutral.
C4b)Dietaryversatility.Neutral.Humpbackchubfeedonsmallfishes,diatoms,planktonic
crustaceans,algae,andaquaticandterrestrialarthropods(U.S.FishandWildlifeService2002;
ValdezandRyel1995).
C4c)Pollinatorversatility(Plantsonly,notapplicable).
C4d)Dependenceonotherspeciesforpropaguledispersal.Neutral.
C4e)Formspartofaninterspecificinteractionnotcoveredby4a‐d.Unknown.
C5a)Measuredgeneticvariation.SomewhatIncrease.Geneticdiversityhasbeenidentifiedasan
issueforthehumpbackchub.Recentgeneticstudieshaveattemptedtounravelgeneticdifferences
betweenroundtailchubandhumpbackchub.Resultsindicatethatacrossitsrange,humpbackchub
androundtailchuboccupysixdistinctmanagementunits(DouglasandDouglas2007).
C5b)Occurrenceofbottlenecksinrecentevolutionaryhistory.Unknown.
C6)Phenologicalresponsetochangingseasonaltemperatureandprecipitationdynamics.
Unknown.
D1)Responsetorecentclimatechange.Unknown.
D2)Modeledfuturechangeinpopulationorrangesize.Unknown.
D3)Overlapofmodeledfuturerangewithcurrentrange.Unknown.
D4)Protectedareas.Unknown.
Literature Cited
Clarkson,R.W.,andM.R.Childs.2000.Temperatureeffectsofhypolimnial‐releasedamsonearlylifestagesofColorado
RiverBasinbig‐riverfishes.Copeia2000:402–412.
Douglas,M.R.andM.E.Douglas.2007.GeneticStructureofHumpbackChubGilacyphaandRoundtailChubG.robustain
theColoradoRiverEcosystem.Report.DepartmentofFish,WildlifeandConservationBiology,ColoradoStateUniversity.
99pp.
Gorman,O.T.andSeales,J.M.1995.Habitatusebytheendangeredhumpbackchub(Gilacypha)intheLittleColorado
River,ArizonanearGrandCanyon.ProceedingofDesertFishesCouncil1994annualsymposium.17‐20NovemberDeath
ValleyNationalPark,FurnaceCreek,CA.
Kaeding,L.R.,Burdick,B.D.,andSchraderP.A.1990.Temporalandspatialrelationsbetweenthespawningofhumpback
chubandroundtailchubintheupperColoradoRiver.TransactionsoftheAmericanFisheriesSociety119:135‐144.
ClimateChangeVulnerabilityAssessmentforColoradoBLM277
Lee,D.S.,GilbertC.R.,HocuttC.H.,JenkinsR.E.,CallisterD.E.,andStaufferJ.R.1981.AtlasofNorthAmericanFreshwater
Fishes:NorthCarolina,NorthCarolinaStateMuseumofNaturalHistory,1981,c1980.
Lukas,J.,J.Barsugli,N.Doesken,I.Rangwala,andK.Wolter.2014.ClimateChangeinColorado:ASynthesistoSupport
WaterResourcesManagementandAdaptation.AReportfortheColoradoWaterConservationBoard.WesternWater
Assessment.
McAda,C.W.2003b.FlowrecommendationstobenefitendangeredfishesintheColoradoandGunnisonRivers.U.S.Fish
andWildlifeService,GrandJunction,CO.
Minckley,W.L.1991.Nativefishesofaridlands:Adwindlingresourceofthedesertsouthwest.USDAForestService.
GeneralTechnicalReportRM‐GTR‐206.pp18.
Modde,T.,W.J.Miller,andR.Anderson.1999.Determinationofhabitatavailability,habitatuse,andflowneedsof
endangeredfishesintheYampaRiverbetweenAugustandOctober.FinalReportofU.S.FishandWildlifeService,Vernal,
UtahtoUpperColoradoRiverEndangeredFishRecoveryProgram,Denver,CO.Onlineathttp://www.fws.gov/mountain‐
prairie/crrip/habitat.htm.
Muth,R.T.,L.W.Crist,K.E.LaGory,J.W.Hayse,K.R.Bestgen,T.P.Ryan,J.K.Lyons,andR.A.Valdez.2000.Flowand
temperaturerecommendationsforendangeredfishesintheGreenRiverdownstreamofFlamingGorgeDam.FinalReport
totheUpperColoradoRiverEndangeredFishRecoveryProgram,Denver,CO.
Paukert,C.P.,L.G.JrCoggins,andC.E.Flaccus.2006.DistributionandmovementofhumpbackchubintheColorado
River,GrandCanyon,basedonrecaptures.Trans.Am.Fish.Soc.135:539–544.
Ray,A.J.,J.Barsugli,andK.Avery.2008.ClimateChangeinColorado:ASynthesistoSupportWaterResources
ManagementandAdaptation.ReporttotheColoradoWaterConservationBoard.
U.S.FishandWildlifeService.2002.Humpbackchub(Gilacypha)RecoveryGoals:amendmentandsupplementtothe
HumpbackChubRecoveryPlan.U.S.FishandWildlifeService,Mountain‐PrairieRegion(6),Denver,Colorado.Valdezand
Ryel.1995.
U.S.FishandWildlifeService.2003.Humpbackchub(Gilacypha)CriticalHabitatshapefile.U.S.FishandWildlifeService,
Mountain‐PrairieRegion(6),Denver,Colorado.Availableonlineathttps://data.doi.gov/dataset/final‐critical‐habitat‐for‐
the‐humpback‐chub‐gila‐cypha.
U.S.FishandWildlifeService.2011.Humpbackchub(Gilacypha)5‐YearReview:SummaryandEvaluation.U.S.Fishand
WildlifeService,UpperColoradoRiverEndangeredFishRecoveryProgram.Denver,CO.29pp.
Valdez,R.A.andR.J.Ryel.1995.LifeHistoryandEcologyoftheHumpbackChubintheColoradoRiverinGrandCanyon,
Arizona.InThecontrolledfloodofGrandCanyon,Editedby:Webb,R.H.,Schmidt,J.C.,Marzolf,G.R.andValdez,R.A.
297–307.Washington,D.C.:AmericanGeophysicalUnion.Monograph110.

278ColoradoNaturalHeritageProgram©2015
Razorback Sucker
Xyrauchentexanus
G1/S1
ListedEndangered
Family:Catostomidae
Photo: James E. Johnson, U.S. Fish & Wildlife Service
Climate Vulnerability Rank: Highly Vulnerable
ThisColoradostate‐widerankisbasedonthefollowingfactors:1)barrierstomovement;2)
potentialdeclineinrunoffandsubsequentdecreaseinflowsintheUpperColoradoRiverBasin;3)
lackofvariationinprecipitationacrossoccupiedhabitatinlast50years;4)requirescleancobble
barsforspawning.
Distribution:RazorbacksuckerarefoundonlyintheupperGreenRiverinUtah,andthelower
YampaRiverinColorado,andoccasionallyintheColoradoRivernearGrandJunction(U.S.Fishand
WildlifeService2002).Habitat:Adultrazorbacksuckeroccupydeepruns,eddies,andflooded
backwaterhabitatsinthesprings;summerhabitatistypicallylow‐velocityruns,pools,andeddies
(USFWS2002).Spawningoccursincobble,gravels,andsand(USFWS2002).Youngrazorback
suckersaretypicallyfoundinquiet,warm,shallowbackwaters(USFWS2002).
EcologicalSystem:Streams
CCVI Scoring
B1)Exposuretosealevelrise.Neutral.
B2)Distributionrelativetobarriers.RazorbacksuckeroccurinthemainstemoftheColorado
Riveraswellasitsmajortributaries(U.S.FishandWildlifeService1998).
B2a)Distributionrelativetonaturalbarriers.Neutral/SomewhatIncrease.Naturalphysical
barrierstomovementintheColoradoRiveranditstributariesarenaturalrapidsandswift
ClimateChangeVulnerabilityAssessmentforColoradoBLM279
turbulentflows,andthesearelikelytofluctuatedependingonflows(U.S.FishandWildlifeService
2002).
B2b)Distributionrelativetoanthropogenicbarriers.Increase.Thedeclineofthespecies
throughouttheColoradoRiverBasinisattributedlargelytoextensivehabitatloss,modification,
andfragmentation,andblockedfishpassagefromdamconstructionandoperations(U.S.Fishand
Wildlife2012).
B3)Impactoflandusechangesresultingfromhumanresponsestoclimatechange.Neutral.
C1)Dispersalandmovements.Decrease.Razorbacksuckerarecapableoftravelinglong
distances.Spawningmigrationsof30to106km(oneway)havebeenreportedintheYampaRiver
inDinosaurNationalMonument(Tyus1987;TyusandKarp1990).
C2ai)Predictedsensitivitytotemperature:historicalthermalniche.Neutral.Consideringthe
meanseasonaltemperaturevariationforoccupiedcells,thespecieshasexperiencedaverage(57.1‐
77°F/31.8‐43.0°C)temperaturevariationinthepast50years.
C2aii)Predictedsensitivitytotemperature:physiologicalthermalniche.Neutral.Razorback
suckerisawarm‐waterfish,andtheavailabilityofwarm,productivewetlandsmaypromotefaster
growthandhighersurvivaloflarvae(Bestgen2008).
C2bi)Predictedsensitivitytochangesinprecipitation,hydrology,ormoistureregime:
historicalhydrologicalniche.SomewhatIncrease.Consideringtherangeofmeanannual
precipitationacrossoccupiedcells,thespecieshasexperiencedslightlylowerthanaverage(11‐20
inches/255‐508mm)precipitationvariationinthepast50years.
C2bii)Predictedsensitivitytochangesinprecipitation,hydrology,ormoistureregime:
physiologicalhydrologicalniche.SomewhatIncrease.Highspringflowshavebeenreportedtobe
importanttoadultsforfeeding,temperatureregulation,andspawning(TyusandKarp1990).
Spawningmovementsandtheappearanceofripefishwereassociatedwithincreasingspringflows
andaveragewatertemperaturesof14°C(range9‐17°Cor48‐63°F)(TyusandKarp1990).There
maybelesswateravailableinfuturetoprovidetheseflows.Mostpublishedresearchindicatesa
declineinrunoffintheUpperColoradoRiverBasinbythemid‐to‐late21stcentury(Lukasetal.
2014;Rayetal.2008).
C2c)Dependenceonaspecificdisturbanceregimelikelytobeimpactedbyclimatechange.
Increase/SomewhatIncrease.Adultrazorbacksuckersspawnovercleancobblebarsduringspring
runoff,andtheirlarvaeflowintofloodplainhabitatsinundatedduringthespringfloods(McAdaand
Wydoski1980;U.S.FishandWildlifeService2002;Wicketal.1982).Thedam‐relatedchangesin
timingandflowlevelsontheColoradoRiveranditstributaries,alongwithchannelization,haveled
toalossoffloodplainnurseriesthatarenecessaryforthesurvivalandreproductionofthe
razorbacksucker(McAdaandWydoski1980).Mostpublishedresearchindicatesadeclineinrunoff
intheUpperColoradoRiverBasinbythemid‐to‐late21stcentury(Lukasetal.2014;Rayetal.
2008),whichcouldleadtofurtherlossanddegradationofhabitatforrazorbacksuckers.
280ColoradoNaturalHeritageProgram©2015
C2d)Dependenceonsnow‐coveredhabitats.Neutral.
C3)Restrictiontouncommongeologicalfeaturesorderivatives.SomewhatIncrease.SeeC2c.
Adultrazorbacksuckersspawnovercleancobblebarsduringspringrunoff,andtheirlarvaeflow
intofloodplainhabitatsinundatedduringthespringfloods(McAdaandWydoski1980;U.S.Fish
andWildlifeService2002;Wicketal.1982).
C4a)Dependenceonotherspeciestogeneratehabitat.Neutral.
C4b)Dietaryversatility.Neutral.Thedietoftherazorbacksuckervariesbylifestage,and
includesinsects,zooplankton,phytoplankton,algae,anddetritus(Bestgen1990;Muthetal.2000).
C4c)Pollinatorversatility(Plantsonly,notapplicable).
C4d)Dependenceonotherspeciesforpropaguledispersal.Neutral.
C4e)Formspartofaninterspecificinteractionnotcoveredby4a‐d.Unknown.
C5a)Measuredgeneticvariation.Neutral.Geneticdiversityhasbeenreportedashighforthe
razorbacksucker(Dowlingetal.1996;Dowlingetal.2005).
C5b)Occurrenceofbottlenecksinrecentevolutionaryhistory.Unknown.
C6)Phenologicalresponsetochangingseasonaltemperatureandprecipitationdynamics.
Unknown.
D1)Responsetorecentclimatechange.Unknown.
D2)Modeledfuturechangeinpopulationorrangesize.Unknown.
D3)Overlapofmodeledfuturerangewithcurrentrange.Unknown.
D4)Protectedareas.Unknown.
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SaltLakeCity,Utah.Contribution44,LarvalFishLaboratory,ColoradoStateUniversity,FortCollins.92pp.
Bestgen,K.2008.EffectsofWaterTemperatureonGrowthofRazorbackSuckerLarvae.WesternNorthAmericanNaturalist68
(1):15‐20.
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Lukas,J.,J.Barsugli,N.Doesken,I.Rangwala,andK.Wolter.2014.ClimateChangeinColorado:ASynthesistoSupport
WaterResourcesManagementandAdaptation.AReportfortheColoradoWaterConservationBoard.WesternWater
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McAda,C.W.andR.W.Wydoski.1980.Therazorbacksucker(Xyrauchentexanus)intheUpperColoradoRiverBasin.974‐
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Ray,A.J.,J.Barsugli,andK.Avery.2008.ClimateChangeinColorado:ASynthesistoSupportWaterResources
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BasinofColoradoandUtah.SouthwesternNaturalist35:427–433.
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Colorado.
U.S.FishandWildlifeService.2002.RazorbacksuckerRecoveryGoals:AmendmentandsupplementtotheRazorback
SuckerRecoveryPlan.U.S.FishandWildlifeService,Region6,Denver,Colorado.
U.S.FishandWildlifeService.2012.FiveYearReview:SummaryandEvaluation.UpperColoradoRiverEndangeredFish
RecoveryProgram.Denver,Colorado,July2012.
Wick,E.J.,C.W.McAda,andR.V.Bulkley.1982.Lifehistoryandprospectsforrecoveryoftherazorbacksucker.Pages120‐
126in:W.H.Miller,H.M.Tyus,andC.A.Carlson(editors).FishesoftheupperColoradoRiversystem:presentandfuture.
AmericanFisheriesSociety,Bethesda,Maryland.

282ColoradoNaturalHeritageProgram©2015
Rio Grande Cutthroat Trout
Oncorhynchusclarkiivirginalis
G4T3/S3
Family:Salmonidae
Nophotoavailable
Climate Vulnerability Rank: Extremely Vulnerable
ThisColoradostate‐widerankisbasedonthefollowingfactors:1)barrierstomovement;2)
potentialdewateringofstreamsintheRioGrandeRiverBasin;3)lackofgeneticdiversity.
Distribution:InColorado,theRioGrandecutthroattroutoccursintheRioGrandeRiverBasin.
Habitat:RioGrandecutthroattroutoccurinclear,cold,highelevationstreams.Adultsusedeep
pools,whilefryusebackwatersandsidechannels(USFWS2014).
EcologicalSystem:Streams
CCVI Scoring
B1)Exposuretosealevelrise.Neutral.
B2a)Distributionrelativetonaturalbarriers.Increase.Insomeheadwaterstreams,waterfalls,
cascades,bedrockchutes,orsubterraneanreachesmaypresentnaturalbarriersthatblock
movementofRioGrandecutthroattrout(Pritchardetal.2008).
B2b)Distributionrelativetoanthropogenicbarriers.SomewhatIncrease.Damsanddiversions
inoccupiedRioGrandecutthroattrouthabitatcanblockdispersalofpopulations,increasingthe
riskofextinction(Zeigleretal.2012).However,theeffectsofconstructedbarriersarecomplex.
Theyalsoprovideabarriertothemovementofnon‐nativefishspeciesthatcompetewithandprey
onRioGrandecutthroattrout(PritchardandCowley2006).
B3)Impactoflandusechangesresultingfromhumanresponsestoclimatechange.Neutral.
ClimateChangeVulnerabilityAssessmentforColoradoBLM283
C1)Dispersalandmovements.SomewhatDecrease.Nodataexistsonaveragemovement
capabilitiesforRioGrandecutthroattrout(PritchardandCowley2006).Cutthroattrouton
Colorado’swestslopewerefoundtomoveamediandistanceof91m‐1.2kmduringthesummer
(SchmetterlingandAdams2004).
C2ai)Predictedsensitivitytotemperature:historicalthermalniche.Neutral.Consideringthe
meanseasonaltemperaturevariationforoccupiedcells,thespecieshasexperiencedaverage(57.1‐
77°F/31.8‐43.0°C)temperaturevariationinthepast50years.
C2aii)Predictedsensitivitytotemperature:physiologicalthermalniche.GreatlyIncrease.
DroughtandincreasedstreamtemperatureshavebeenidentifiedasamajorthreattoRioGrande
cutthroattrout(Haaketal.2010).DroughtsinthesouthwesternUnitedStatesareexpectedto
increaseinfrequencyandseverity(HoerlingandEischeid2007).Thiscouldresultinstream
dewateringandadecreaseinavailablehabitat(U.S.FishandWildlifeService2014;Zeigleretal.
2012).AverageannualairtemperaturehasincreasedacrosstherangeofRioGrandecutthroat
troutsincethemid‐20thcentury,andthistrendcouldresultinelevatedstreamtemperaturesthat
areunsuitableforRioGrandecutthroattroutthatrelyoncoldwaterhabitattocompletetheirlife
cycle(U.S.FishandWildlifeService2014;Williamsetal.2009;Ziegleretal.2012).
C2bi)Predictedsensitivitytochangesinprecipitation,hydrology,ormoistureregime:
historicalhydrologicalniche.SomewhatDecrease.Consideringtherangeofmeanannual
precipitationacrossoccupiedcells,thespecieshasexperiencedgreaterthanaverage(>40
inches/1,016mm)precipitationvariationinthepast50years.
C2bii)Predictedsensitivitytochangesinprecipitation,hydrology,ormoistureregime:
physiologicalhydrologicalniche.GreatlyIncrease.Reducedstreamflowhasalreadybeen
observedthroughouttherangeofRioGrandecutthroattrout(Zeigleretal.2012).Recentclimate
modelspredictdecreasesinannualstreamflowintheRioGrandeBasin(Lukasetal.2014).Stream
dryingreducesavailablehabitatforalllifestagesofRioGrandecutthroattrout(seematrixin
USFWS2014).
C2c)Dependenceonaspecificdisturbanceregimelikelytobeimpactedbyclimatechange.
Neutral.RioGrandecutthroattroutarelocatedinheadwaterstreams.Theyspawnfollowingpeak
runofflevelsfromsnowmelt(Behnke2002;PritchardandCowley2006).Climatechangehas
shiftedpeakrunofffromsnowmeltapproximately10daysearlierthan45yearsago(Zeigleretal.
2012).EarlierrunoffcouldposebenefitsandthreatstoRioGrandecutthroattrout.Young‐of‐year
wouldbenefitfromalongergrowingseason,butalongseasonoflowflowscouldleadtoincreased
streamtemperaturesandstreamintermittencyoutsideofthetolerancerangeforthespecies
(USFWS2014).
C2d)Dependenceonsnow‐coveredhabitats.Neutral.AsnotedaboveinC2c,RioGrande
cutthroattroutarelocatedinheadwaterstreams.Theyspawnfollowingpeakrunofflevelsfrom
snowmelt(Behnke2002;PritchardandCowley2006).
284ColoradoNaturalHeritageProgram©2015
C3)Restrictiontouncommongeologicalfeaturesorderivatives.Neutral/SomewhatIncrease.
Sediment‐freegravelsandcobblesarenecessaryforproducingaquaticinsectsforfoodandcreate
spawninghabitats(USFWS2014).
C4a)Dependenceonotherspeciestogeneratehabitat.Unknown.
C4b)Dietaryversatility.Neutral.StudiesofColoradoRiverandRioGrandecutthroattrout
indicatethatmidgelarvae,caddisflies,andmayflies,aswellasarangeofotherbenthicpreyitems
comprisethemaindietofthesenativetroutspecies(Bozeketal.1994;PritchardandCowley2006;
MooreandGregory1988;Youngetal.1997).
C4c)Pollinatorversatility(Plantsonly,notapplicable).
C4d)Dependenceonotherspeciesforpropaguledispersal.Neutral.
C4e)Formspartofaninterspecificinteractionnotcoveredby4a‐d.Neutral.
C5a)Measuredgeneticvariation.Increase.Geneticdiversityisaconservationconcernforthis
speciesthathasexperiencedprecipitousdeclinesinthelastcentury.Recentstudieshaveshown
thattherearetwo“evolutionarysignificantunits”ofRioGrandecutthroattrout:oneintheRio
GrandeBasin,andoneinthePecosandCanadianbasins(Pritchardetal.2009).
C5b)Occurrenceofbottlenecksinrecentevolutionaryhistory.Unknown.
C6)Phenologicalresponsetochangingseasonaltemperatureandprecipitationdynamics.
Unknown.
D1)Responsetorecentclimatechange.Unknown.
D2)Modeledfuturechangeinpopulationorrangesize.Unknown.
D3)Overlapofmodeledfuturerangewithcurrentrange.Unknown.
D4)Protectedareas.Unknown.
Literature Cited
Behnke,R.J.2002.TroutandsalmonofNorthAmerica.FreePress,NewYork.
Bozek,M.A.,L.D.Debrey,andJ.A.Lockwood.1994.DietoverlapamongsizeclassesofColoradoRivercutthroattrout
(Oncorhynchusclarkipleuriticus)inahigh‐elevationmountainstream.Hydrobiologia273:9‐17.
Haak,A.L.,J.E.Williams,D.Isaak,A.Todd,C.Muhlfeld,J.L.Kershner,R.Gresswell,S.Hostetler,andH.M.Neville.2010.
Thepotentialinfluenceofchangingclimateonthepersistenceofsalmonidsoftheinlandwest.U.S.GeologicalSurvey,
Open‐FileReport2010‐1236,Reston,Virginia.AccessedNov13,2014.Onlineat:pubs.usgs.gov/of/2010/1236/.
Hoerling,M.,andJ.Eischeid.2007.PastpeakwaterintheSouthwest.SouthwestHydrology6:18–19,35.
ClimateChangeVulnerabilityAssessmentforColoradoBLM285
Lukas,J.,J.Barsugli,N.Doesken,I.Rangwala,andK.Wolter.2014.ClimateChangeinColorado:ASynthesistoSupport
WaterResourcesManagementandAdaptation.AReportfortheColoradoWaterConservationBoard.WesternWater
Assessment.
Moore,K.M.S.andS.V.Gregory.1988.SummerhabitatutilizationandecologyofcutthroattroutfrySalmoclarkii.in
CascadeMountainUSAstreams.CanadianJournalofFisheriesandAquaticSciences45:921‐1930.
PritchardV.L.,J.L.Metcalf,K.Jones,A.P.Martin,D.E.Cowley.2008.PopulationstructureandgeneticmanagementofRio
Grandecutthroattrout(Oncorhynchusclarkiivirginalis).ConservationGenetics,10,1209–1221.
Pritchard,V.L.,andD.E.Cowley.2006.RioGrandecutthroattrout(Oncorhynchusclarkiivirginalis):atechnical
conservationassessment.U.S.DepartmentofAgricultureForestService,RockyMountainRegion,SpeciesConservation
Project,FortCollins,Colorado.Available:www.fs.fed.us/r2/projects/scp/assessments.(September2008).
Schmetterling,D.A.andS.B.Adams.2004.Summermovementswithinthefishcommunityofasmallmontanestream.
NorthAmericanJournalofFisheriesManagement24:1163–1172
U.S.FishandWildlifeService.2014.EndangeredandThreatenedWildlifeandPlants;12‐MonthFindingonaPetitionTo
ListRioGrandeCutthroatTroutasanEndangeredorThreatenedSpecies.DocketNo.FWS–R2–ES–2014–0042;
4500030113.
Young,M.K.,Rader,R.B.,andBelish,T.A.1997.“InfluenceofMacroinvertebrateDriftandLightontheActivityand
MovementofColoradoRiverCutthroatTrout.”TransactionsoftheAmericanFisheriesSociety,126,428‐437.
Williams,J.E.,A.L.Haak,H.M.Neville,andW.T.Colyer.2009.Potentialconsequencesofclimatechangetopersistenceof
cutthroattroutpopulations.NorthAmericanJournalofFisheriesManagement29:533–548.
Ziegler,M.P,A.S.Todd,C.A.Caldwell.2012.EvidenceofRecentClimateChangewithintheHistoricRangeofRioGrande
CutthroatTrout:ImplicationsforManagementandFuturePersistence,TransactionsoftheAmericanFisheriesSociety
141(4):1045‐1059.

286ColoradoNaturalHeritageProgram©2015
Roundtail Chub
Gilarobusta
G3/S2
Family:Cyprinidae
Climate Vulnerability Rank: Highly Vulnerable
ThisColoradostate‐widerankisbasedonthefollowingfactors:1)barrierstomovement;2)
potentialdeclineinrunoffandsubsequentdecreaseinflowsintheUpperColoradoRiverBasin;3)
potentialshiftintimingofspawningthatcouldleadtolowerrecruitment;4)lackofgenetic
diversity.
Distribution:InColorado,theroundtailchubisfoundontheWesternSlopeintheUpperColorado
RiverBasin.ThemapaboveisbasedoninformationprovidedintheColoradoParksandWildlife
(2015)conservationassessmentplandraft.Habitat:Roundtailchuboccupymainstemand
tributariesstreamsintheUpperColoradoRiverBasin.Adultsuseeddiesandpoolsnearareaswith
strongcurrentsandboulders(CPW2015);whilesjuvenilesaremostfrequentlyfoundinquiet,
shallowbackwaters(Brouderetal.2000).
EcologicalSystem:Streams
CCVI Scoring
B1)Exposuretosealevelrise.Neutral.
B2a)Distributionrelativetonaturalbarriers.SomewhatIncrease/Neutral.Adultroundtailchub
occupydeeppoolsandrunsinmainstemandsmallertributarysystemoftheColoradoRiverBasin
(Bestgenetal.2011).Larvaepreferlowvelocitybackwaters,young‐of‐the‐yearoccupyshallow,low
velocityhabitats,andjuvenilesoccupypools(Bestgenetal.2011).Rapids,swiftturbulentflows,
andwaterfallscouldcreatenaturalbarrierstomovementofroundtailchubduringhighflows,but
thesebarriersarelikelyseasonal.HighsalinitylevelsintheDoloresRiverfromParadoxValley
ClimateChangeVulnerabilityAssessmentforColoradoBLM287
downstreamtoSanMiguelcouldalsoposeasanaturalbarrierwhenconcentrationsarehighduring
lowflows(Bestgenetal.2011).
B2b)Distributionrelativetoanthropogenicbarriers.Increase.Theconstructionofdamsalong
themainstemoftheColoradoRiveranditstributarieshasfragmentedandinundatedriverine
habitat;releasedcold,clearwaters;alteredecologicalprocessesandsedimentregimes;affected
seasonalavailabilityofhabitat;andblockedfishpassage(MarshandDouglas1997;Minckleyand
Deacon1968;U.S.FishandWildlifeService2002;ValdezandRyel1995).Roundtailchubdeclines
arecommoninimpoundmentsafterreservoirconstruction(BezzeridesandBestgen2002).
WolfordMountainReservoirhoststheonlyreservoir‐dwellingpopulationofroundtailchubin
Colorado(Ewert2010).Fishpassagewayshavebeencreatedfortheroundtailchubandother
nativefishatdamsitesintheColoradoRivernearPalisadeandontheGunnisonRiver(Landers
2012).TheGreenRiverDaminUtahisslatedforrehabilitation,andthefinalplansforrenovation
includeafishpassagewaytoallowfortheupstreamanddownstreammovementofnativefishes,
includingroundtailchub(U.S.DepartmentofAgriculture2014).
B3)Impactoflandusechangesresultingfromhumanresponsestoclimatechange.Neutral.
C1)Dispersalandmovements.Neutral.Roundtailchubtravel5‐80kmduringspawning(Bestgen
etal.2011).
C2ai)Predictedsensitivitytotemperature:historicalthermalniche.Neutral.Consideringthe
meanseasonaltemperaturevariationforoccupiedcells,thespecieshasexperiencedaverage(57.1‐
77°F/31.8‐43.0°C)temperaturevariationinthepast50years.
C2aii)Predictedsensitivitytotemperature:physiologicalthermalniche.Neutral.The
roundtailchubisadaptedtothelarge,warm‐waterriversandstreamsoftheColoradoRiverBasin.
Roundtailchubpreferstreamtemperaturesthatrangefrom18‐20˚C(BezzeridesandBestgen
2002).DamreleaseshaveledtocolderwatertemperaturesintheBasin,andthesearesuggestedas
areasonfortheoveralldeclineinroundtailchubpopulations(Bestgenetal.2011).
C2bi)Predictedsensitivitytochangesinprecipitation,hydrology,ormoistureregime:
historicalhydrologicalniche.SomewhatDecrease.Consideringtherangeofmeanannual
precipitationacrossoccupiedcells,thespecieshasexperiencedgreaterthanaverage(>40
inches/1,016mm)precipitationvariationinthepast50years.
C2bii)Predictedsensitivitytochangesinprecipitation,hydrology,ormoistureregime:
physiologicalhydrologicalniche.SomewhatIncrease.Abundanceofroundtailchubwas
positivelycorrelatedwithmoderatetohighbaseflowsintheColoradoRiverBasin(Andersonand
Stewart2007).However,theremaybelesswateravailableinfuturetoprovidetheseflows.Most
publishedresearchindicatesadeclineinrunoffintheUpperColoradoRiverBasinbythemid‐to‐
late21stcentury(Lukasetal.2014;Jayetal.2008).
C2c)Dependenceonaspecificdisturbanceregimelikelytobeimpactedbyclimatechange.
Increase.RoundtailchubtypicallyspawninJunetoearlyJulywhenwatertemperaturesrangefrom
16‐22˚C(ColoradoParksandWildlife2015).Mostpublishedresearchindicatesadeclineinrunoff
288ColoradoNaturalHeritageProgram©2015
intheUpperColoradoRiverBasinbythemid‐to‐late21stcentury(Lukasetal.2014;Jayetal.
2008).ThiscouldcauselowflowsinAprilandMay,creatingwarmerwatertemperaturesthatcould
prematurelyinitiatespawningofroundtailchub,andsubsequentcoldhighflowscouldkilleggsand
larvae(Bestgenetal.2011).
C2d)Dependenceonsnow‐coveredhabitats.Neutral.
C3)Restrictiontouncommongeologicalfeaturesorderivatives.Neutral.Roundtailchub
spawnovergravelindeeppoolsandruns(BezzeridesandBestgen2002;Brouderetal.2000).
C4a)Dependenceonotherspeciestogeneratehabitat.Neutral.
C4b)Dietaryversatility.Neutral.Roundtailchubfeedonaquaticandterrestrialinsects,fish,
snails,algae,andoccasionallylizards(Bestgen2000;Brouder2001;ColoradoParksandWildlife
2015;Osmundson1999;SiglerandSigler1996).
C4c)Pollinatorversatility(Plantsonly,notapplicable).
C4d)Dependenceonotherspeciesforpropaguledispersal.Neutral.
C4e)Formspartofaninterspecificinteractionnotcoveredby4a‐d.Unknown.
C5a)Measuredgeneticvariation.SomewhatIncrease.Theroundtailchubisverycloselyrelated
tothehumpbackchub,andgeneticdiversityhasbeenidentifiedasaconservationissueforthese
twospecies(Clarksonetal.2012;DouglasandDouglas2007).
C5b)Occurrenceofbottlenecksinrecentevolutionaryhistory.Unknown.
C6)Phenologicalresponsetochangingseasonaltemperatureandprecipitationdynamics.
Unknown.
D1)Responsetorecentclimatechange.Unknown.
D2)Modeledfuturechangeinpopulationorrangesize.Unknown.
D3)Overlapofmodeledfuturerangewithcurrentrange.Unknown.
D4)Protectedareas.Unknown.
Literature Cited
Bestgen,K.R.2000.PersonalcommunicationwithDirectorofColoradoStateUniversity’sLarvalFishLabtoColorado
ParksandWildlife,FortCollins,Colorado.
Bestgen,K.R.,P.Budy,andW.J.Miller.2011.StatusandtrendsofflannelmouthsuckerCatostomuslapipinnis,bluehead
suckerCatostomusdiscobolus,androundtailchubGilarobusta,intheDoloresRiver,Colorado,andopportunitiesfor
populationimprovement:PhaseIIreport.PreparedforLowerDoloresPlanWorkingGroup.Onlineat
http://warnercnr.colostate.edu/docs/fwcb/lfl/PDF/LFL‐166‐Bestgen_et_al‐2011‐Rpt.pdf.
ClimateChangeVulnerabilityAssessmentforColoradoBLM289
Bezzerides,N.,andK.R.Bestgen.2002.StatusReviewofRoundtailChubGilarobusta,FlannelmouthSuckerCatostomus
latipinnis,andBlueheadSuckerCatostomusdiscobolusintheColoradoRiverBasin.Finalreport.SubmittedtoU.S.
DepartmentoftheInterior,BureauofReclamation,SaltLakeCity,Utah.LarvalFishLaboratoryContribution118,
ColoradoStateUniversity,Ft.Collins.
Brouder,M.J.,D.D.Rogers,andL.D.Avenetti.2000.Lifehistoryandecologyoftheroundtailchub(Gilarobusta)fromtwo
streamsintheVerdeRiverBasin.TechnicalGuidanceBulletinNo.3–July2000.ArizonaGameandFishDepartment
ResearchBranch,FederalAidinSportfishRestorationProjectF‐14‐R,Phoenix.
Brouder,M.J.2001.Effectsoffloodingonrecruitmentofroundtailchub,Gilarobusta,inasouthwesternriver.The
SouthwesternNaturalist46(3):302‐310.
Clarkson,R.W.,P.C.MarshandT.E.Dowling.2012.Populationprioritizationforconservationofimperiledwarmwater
fishesinanarid‐regiondrainage.AquaticConservation:MarineandFreshwaterEcosystems22(4):498‐510.
ColoradoParksandWildlife.2015.StateofColoradoConservationandManagementPlanfortheRoundtailChub(Gilia
robusta),BlueheadSucker(Catostomusdiscobolus)andFlannelmouthSucker(Catostomuslatipinnis).UnpublishedDraft.
Douglas,M.R.andM.E.Douglas.2007.GeneticStructureofHumpbackChubGilacyphaandRoundtailChubG.robustain
theColoradoRiverEcosystem.Report.DepartmentofFish,WildlifeandConservationBiology,ColoradoStateUniversity.
99pp.
Ewert,J.2010.WolfordMountainReservoir,fishsurveyandmanagementdata.ColoradoDivisionofWildlife.Available
from
http://cpw.state.co.us/documents/fishing/fisherywatersummaries/summaries/northwest/wolfordmountainreservoir.p
df
Landers,J.2012.ColoradoDamModifiedtoIncludeInnovativeFishwaysandBoatPassage.CivilEngineering82(11):24‐
28.
Lukas,J.,J.Barsugli,N.Doesken,I.Rangwala,andK.Wolter.2014.ClimateChangeinColorado:ASynthesistoSupport
WaterResourcesManagementandAdaptation.AReportfortheColoradoWaterConservationBoard.WesternWater
Assessment.
Marsh,P.C.,andM.E.Douglas.1997.Predationbyintroducedfishesonendangeredhumpbackchubandothernative
speciesintheLittleColoradoRiver,Arizona.TransactionsoftheAmericanFisheriesSociety126:343–346.
Minckley,W.L.,andJ.E.Deacon.1968.Southwesternfishesandtheenigmaof“EndangeredSpecies”:man’sinvasionof
desertscreatesproblemsfornativeanimals,especiallyforfreshwaterfishes.Science,159:1424‐1432.
Osmundson,D.B.1999.LongitudinalvariationinfishcommunitystructureandwatertemperatureintheUpperColorado
River:implicationsforColoradopikeminnowhabitatsuitability.FinalReportforRecoveryImplementationProgram,
ProjectNo.48.U.S.FishandWildlifeService,GrandJunction,Colorado.
Ray,A.J.,J.Barsugli,andK.Avery.2008.ClimateChangeinColorado:ASynthesistoSupportWaterResources
ManagementandAdaptation.ReporttotheColoradoWaterConservationBoard.
Sigler,W.F.andJ.W.Sigler.1996.FishesofUtah:ANaturalHistory.UniversityofUtahPress,SaltLakeCity.
U.S.DepartmentofAgriculture.2014.FinalEnvironmentalImpactStatement.GreenRiverDiversionRehabilitation
Project.AccessedOctober14,2014onlineat
http://www.nrcs.usda.gov/wps/portal/nrcs/detail/ut/programs/planning/ewpp/?cid=nrcs141p2_034037.

290ColoradoNaturalHeritageProgram©2015
Great Basin Silverspot
Speyerianokomisnokomis
G3T1/S1
Family:Nymphalidae
 
Climate Vulnerability Rank: Highly Vulnerable
ThisColoradostatewiderankisbasedon:theprojectedincreaseintemperatureanddroughtinthe
assessedarea,theinabilityofthesilverspottodisperseacrossdrylandscapes,itsdependenceon
wetlandhabitatwithinanaridlandscape,thedryingofitswetlandhabitatduetoprojected
frequenciesofdrought,modificationstohydrology(e.g.,waterdiversionprojects,cappingsprings,
anddrainingwetlands)tosupporttheagricultureandlivestockindustriesastheavailabilityof
waterresourcesdeclines,limitedprecipitationvariationthesilverspothashistoricallyexperienced,
theincreasedthreattosuitablehabitatfromwildfirecausedbydroughtandwarming,dependence
onalarvalhostplantthatisrestrictedtowetlands,andlowlevelsofgeneticvariabilityquestioning
thesilverspotsadaptabilitytoachangingenvironment.Regionalannualaveragetemperaturesare
projectedtoriseby2.5°Fto5.5°Fby2041‐2070andby5.5°Fto9.5°Fby2070‐2099with
continuedgrowthinglobalemissions(A2emissionsscenario),withthegreatestincreasesinthe
summerandfall(Melilloetal.2014).Underacontinuationofcurrentrisingemissionstrends(A2),
reducedwinterandspringprecipitationisconsistentlyprojectedforthesouthernpartofthe
Southwestby2100elevatingthepotentialforwildfire(Melilloetal.2014).
Distribution:InColorado,coloniesoccuratonlyfourpreviouslyknownlocationsinLaPlata,Mesa,
Montrose,andOuraycounties(CNHP2004).Habitat:TheNokomisfritillaryisassociatedwiththe
UpperSonoran(pinyon‐juniper,variousshrubs)andCanadian(fir‐spruce‐tamarack,somepine,
aspen‐maple‐birch‐alder‐hemlock)LifeZonesofthesouthwesternUnitedStatesandnorthern
Mexico(Hammond1974,Scott1986,Selby2007).Habitatsaregenerallydescribedaspermanent
spring‐fedmeadows,seeps,marshes,andboggystreamsidemeadowsassociatedwithflowing
waterinaridcountry(Hammond1974,Scott1986,TildenandSmith1986,OplerandWright1999,
BrockandKaufman2003,Selby2007).
ClimateChangeVulnerabilityAssessmentforColoradoBLM291
CCVI Scoring
B1)Exposuretosealevelrise.Neutral.
B2a)Distributionrelativetonaturalbarriers.Increase.Aridlandscapesseparatingdesert
streamsandwetlandsareaseverebarriertothisspecies.GreatBasinsilverspotbutterfliesdonot
migratewithdocumentedroutinedispersaldistancesofonlyupto4km(Fleischmanetal.2002).
Theyrequirestreamsidemeadowsandseepageareasduringtheiradultflightperiodandfortheir
larvalstage.InthearidSouthwest,wherethisbutterflylives,thesehabitatconditionsarewidely
separatedandisolated(Selby2007)andpopulationsatonelocalewillnotcrossaridlandscapesto
distantcoloniesexistingatotherdesertstreams/wetlands.
B2b)Distributionrelativetoanthropogenicbarriers.Neutral.Anthropogenicbarriersarenot
thoughttobeaconcernforthisspeciesbecauseoftheundevelopeddesertlandscapesthisspecies
inhabits.
B3)Impactoflandusechangesresultingfromhumanresponsestoclimatechange.Increase.
Modificationstohydrology(e.g.,waterdiversionprojects,cappingsprings,anddrainingwetlands)
tosupporttheagricultureandlivestockindustriesarethegreatesthistoric,current,andfuture
threattothelong‐termsurvivaloftheGreatBasinsilverspotbutterflyintheassessedarea.
Increasedwaterdemand,combinedwithreducedavailabilityduetoclimatechange(Karletal.
2009),willnegativelyimpactthisspecies.
C1)Dispersalandmovements.Neutral.TheGreatbasinsilverspothasbeendocumentedto
routinelydisperseupto4km(2.5miles),andinonestudy26percentoftherecapturedbutterflies
hademigratedfromtheirinitialcapturepatch(Fleischmanetal.2002).
C2ai)Predictedsensitivitytotemperature:historicalthermalniche.Neutral.Therange
occupiedbytheGreatBasinsilverspotintheassessedareahasexperiencedanaverage(51.7‐77°
F/31.8‐43.0°C)zonalmeanseasonaltemperatureoverthelast50years
C2aii)Predictedsensitivitytotemperature:physiologicalthermalniche.Somewhatdecrease.
TheGreatBasinSilverspothasapreferenceforwarmerenvironmentsandisassociatedwitharid
desertlandscapesoftheUpperSonoranLifeZone(Selby2007).
C2bi)Predictedsensitivitytochangesinprecipitation,hydrology,ormoistureregime:
historicalhydrologicalniche.Somewhatdecrease.WithintheassessedareatheGreatBasin
silverspothasexperiencedgreaterthanaverage(>40inches/1,016mm)precipitationvariationin
thepast50years.
C2bii)Predictedsensitivitytochangesinprecipitation,hydrology,ormoistureregime:
physiologicalhydrologicalniche.Greatlyincrease.TheGreatbasinsilverspotiscompletely
dependentuponwidelyseparatedisolatedspotswheretherearepermanentspring‐fedmeadows,
seeps,marshes,andboggystreamsidemeadowsassociatedwithflowingwaterinthemidstof
otherwisearidcountry(Hovanitz1970,BrockandKaufman2003).Inthefuture,climatechangeis
292ColoradoNaturalHeritageProgram©2015
projectedtoincreasedroughtfrequency(Melilloetal.2014,whichmayreducethesehabitats
withintheassessedarea.
C2c)Dependenceonaspecificdisturbanceregimelikelytobeimpactedbyclimatechange.
Increase.Climatechangeisprojectedtoincreasewildfirefrequencyintheassessedarea(Melillo
2014).Firecancausedirectmortalityoflarvaeandeliminaterequiredhostplants.Giventhese
factors,itshouldbeassumedthatextensive(e.g.,burningallormostofthehabitatinanareaatone
time)orfrequent(e.g.,everyonetotwoyears)firesarelikelytonegativelyaffectbutterfly
populations(Selby2007).Alternatively,lowseverityandinfrequent(every5years)firecan
maintainthecomplexofwetmeadows,willows,andotherwoodywetlandspeciesthatprovides
optimalmicroclimatesforthelarvalfoodplant(bogviolet)andadultnectarplantstheGreatBasin
silverspotbutterflyneeds.
C2d)Dependenceonsnow‐coveredhabitats.Neutral.TheGreatBasinsilverspotisnot
dependentonhabitatswithice,snow,oronsnowpack.
C3)Restrictiontouncommongeologicalfeaturesorderivatives.Neutral.TheGreatBasin
silverspotisnotdependentuponanyuncommongeologicalelements.
C4a)Dependenceonotherspeciestogeneratehabitat.Increase.TheGreatBasinsilverspotis
dependentonthepresenceofanadequatesupplyofthelarvalfoodplant(i.e.,bogviolet[Viola
nephrophylla])(NatureServe2014).Microhabitatconditionsforthebogvioletincludesoggysoil
andshade,oftenundershrubssuchaswillows(Baird1942).Willowsareusuallypresent
(Hammond1974)andprobablyhelptocreatethemicroclimatethatthevioletsneed.Climate
changeisprojectedtoincreasedroughtfrequencywithintheassessedarea(Melilloetal.2014),
reducingthewateravailableforsustainingtheplantcommunitiesthebogvioletdependsupon.
C4b)Dietaryversatility.Bogviolet(Violanephrophylla)istheexclusivelarvalfoodplant.Adults
feedonnectarfromawiderangeoffloweringalpineplants(OplerandWright1999).
C4d)Dependenceonotherspeciesforpropaguledispersal.Neutral.TheGreatBasinfritillaryis
aself‐disperser.
C4e)Formspartofaninterspecificinteractionnotcoveredby4a‐d.Neutral.Noother
interspecificinteractionsareimportanttothepersistenceoftheGreatBasinfritillary.
C5a)Measuredgeneticvariation.Increase.ColoniesofNokomisfritillarysubspeciestendtobe
small,local,restrictedtoarelativelynarrowelevationrange,andsusceptibletooccasionalsevere
populationdeclines;consequently,lowlevelsofheterozygosityarenotunexpected.Genetic
researchontheGreatBasinsilverspotindicatesthatthereisverylittlegeneticvariationinthese
populations(Selby2007).
C5b)Occurrenceofbottlenecksinrecentevolutionaryhistory.Unknown.
ClimateChangeVulnerabilityAssessmentforColoradoBLM293
C6)Phenologicalresponsetochangingseasonaltemperatureandprecipitationdynamics.
Unknown.
D1)Responsetorecentclimatechange.Unknown.
D2)Modeledfuturechangeinpopulationorrangesize.Unknown.
D3)Overlapofmodeledfuturerangewithcurrentrange.Unknown.
D4)Protectedareas.Unknown.
Literature Cited
Baird,V.B.1942.WildvioletsofNorthAmerica.UniversityofCaliforniaPress,Berkeley,CA.
Brock,J.P.andK.Kaufman.2003.ButterfliesofNorthAmerica.HoughtonMifflin,NewYork,NY.383pp.
ColoradoNaturalHeritageProgram(CNHP).2004.Nokomisfritillaryelementglobalrank(EGR)report.ColoradoNatural
HeritageProgram,FortCollins,CO.
Fleishman,E.,C.Ray,P.Sjögren‐Gulve,C.L.Boggs,andD.D.Murphy.2002.Assessingtherelativerolesofpatchquality,
area,andisolationinpredictingmetapopulationdynamics.ConservationBiology16:706‐716.
Hammond,P.C.1974.AnecologicalsurveyofthenymphalidbutterflygenusSpeyeria.M.S.Thesis,UniversityofNebraska,
Lincoln,NE.
Hovanitz,W.1969(1970).Habitat:Argynnisnokomis.JournalofResearchontheLepidoptera8(1):20.
Karl,T.R.,J.M.Melillo,andT.C.Peterson,(eds.).2009.GlobalClimateChangeImpactsintheUnitedStates.Cambridge
UniversityPress.
Melillo,J.M.,T.C.Richmond,andG.W.Yohe,Eds.,2014:ClimateChangeImpactsintheUnitedStates:TheThirdNational
ClimateAssessment.U.S.GlobalChangeResearchProgram,841pp.doi:10.7930/J0Z31WJ2.
NatureServe.2014.NatureServeExplorer:Anonlineencyclopediaoflife[webapplication].Version7.1.NatureServe,
Arlington,Virginia.Availablehttp://explorer.natureserve.org[2/6/2015].
Opler,P.A.andA.BWright.1999.Petersonfieldguidetowesternbutterflies.Revisededition.HoughtonMifflinCo.,
Boston,MA.540pp.
Scott,J.A.1986.ThebutterfliesofNorthAmerica.StanfordUniversityPress,Stanford,CA.583pp.
Selby,G.2007.GreatBasinSilverspotButterfly(Speyerianokomisnokomis[W.H.Edwards]):atechnicalconservation
assessment.[Online].USDAForestService,RockyMountainRegion.Available:
http://www.fs.fed.us/r2/projects/scp/assessments/greatbasinsilverspotbutterfly.pdf[1/23/2015].
Tilden,J.W.andA.C.Smith.1986.Afieldguidetowesternbutterflies.Houghton‐MifflinCo.,Boston,MA.370pp.23color
plates.
294ColoradoNaturalHeritageProgram©2015
American Beaver
Castorcanadensis
G5/S4
Family:Castoridae
Climate Vulnerability Rank: Moderately Vulnerable
ThisColoradostate‐widerankisbasedon:thelimitedthermalnicheforC.canadensis;C.
canadensis’relianceonaquaticenvironments;andC.canadensis’susceptibilitytovaryingwater
availability.
Distribution:C.canadensisisfoundinnearlyallwaterwaysinColorado.Habitat:C.canadensis
livesandfeedsinandaroundwaterwaysofColorado,butaremostabundantinareaswithaspen,
cottonwood,orwillowespeciallyinbroadglacialvalleyswithlowstreamgradients(Armstronget
al.2011).Elevation:3,300–11,000feet
.
EcologicalSystem:Waterwaysandadjacentriparianforests
CCVI Scoring
B1)Exposuretosealevelrise.Neutral.
B2a)Distributionrelativetonaturalbarriers.Neutral.Therearefewnaturalbarriersfor
beavers.
B2b)Distributionrelativetoanthropogenicbarriers.Neutral.Becausebeaversareadeptat
colonizingwaterbodiesandareubiquitousinNorthAmerica,therearefewanthropogenicbarriers.
B3)Impactoflandusechangesresultingfromhumanresponsestoclimatechange.Neutral.
Thereisnotclimate‐changemitigatingenergydevelopmentthatwilllimitbeaversuccess.
ClimateChangeVulnerabilityAssessmentforColoradoBLM295
C1)Dispersalandmovements.SomewhatDecrease.Femalestypicallydispersefurtherthan
males(10kmvs.3km)(Sunetal.2000).Juvenilesindifferentsystemsmaydispersalless(2–5
km)(McNewandWoolf2005).Dispersaldistancesfortransplantedbeavercanbemuchhigher
(BoyleandOwens2007),butnaturaldispersalistypicallylessthan10km(VanDeelenand
Pletscher1986,Sunetal.2000).
C2ai)Predictedsensitivitytotemperature:historicalthermalniche.Neutral.Muchofthe
beaverrangeinColoradofallswithinthe55‐77°Frange.
C2aii)Predictedsensitivitytotemperature:physiologicalthermalniche.Increase
Vulnerability.Thermoneutralzoneforbeaversisbetween32‐82°F(MacArthur1989)andthe
speciesspendsmostofitstimeinwaterwherethermoregulationincoolaquaticenvironmentscan
bephysiologicallychallenging(MacArthurandDyck1990).However,beaversaretiedtoaquatic
environmentsthatmaybecomemorescarceandwarminganddryingcontinue.
C2bi)Predictedsensitivitytochangesinprecipitation,hydrology,ormoistureregime:
historicalhydrologicalniche.SomewhatIncreaseVulnerability.BasedontheClimateWizard
mapofhistorichydrologicvariation,muchoftherangeinColoradovariesfromthelowestvariation
tomid‐levelsofvariability.
C2bii)Predictedsensitivitytochangesinprecipitation,hydrology,ormoistureregime:
physiologicalhydrologicalniche.GreatlyIncreasevulnerability.Beaversare100%relianton
aquaticenvironmentsforsubsistence,anditislikelyasclimatedriesandwarmsthedistribution
(andbeaverabundance)willbereduced.
C2c)Dependenceonaspecificdisturbanceregimelikelytobeimpactedbyclimatechange.
SomewhatIncreaseVulnerability.Beaversdonotrelyonaparticulardisturbanceregimeanddo
notneedanabsenceofdisturbance.Themostregularnon‐essentialdisturbanceiswater
availability.Populationsofbeaveronlow‐flowstreamswilllikelybethemostdisturbedby
alternationsinhydrology(BoyleandOwens2007).Beaversandtheirhabitatcanbechallengedby
theabsenceofwater(drought)oranabundanceofwater(flooding),butcanmodifytheir
environmenttolimittheimpactofthesestressors.Climatechangeislikelytoincreasethe
frequencyofdroughtandthismaylimitbeaverdistributionandnumbers.
C2d)Dependenceonsnow‐coveredhabitats.Neutral.Thereisnoknownrelationshipofthis
speciestosnoworice‐coveredhabitats.
C3)Restrictiontouncommongeologicalfeaturesorderivatives.Neutral.Thisspeciesisnot
knowntospecializeonuncommongeologicalfeatures.
C4a)Dependenceonotherspeciestogeneratehabitat.Neutral.Beaversgeneratetheirown
habitatviadambuilding.
C4b)Dietaryversatility.Neutral.Beaversaregeneralistherbivoresfeedingoninnerbark,twigs,
leaves,andbudsofdeciduouswoodyplants,andherbaceousandaquaticplants(BoyleandOwens
2007).
296ColoradoNaturalHeritageProgram©2015
C5a)Measuredgeneticvariation.Unknown.Nodataareavailableforgeneticvariabilitywithin
NorthAmericanbeavers.
C5b)Occurrenceofbottlenecksinrecentevolutionaryhistory.onlyif5Aisunknown.
C6)Phenologicalresponsetochangingseasonaltemperatureandprecipitationdynamics.
Unknown.Nodataavailable.
D1)Responsetorecentclimatechange.Unknown.Nodataavailable.
D2)Modeledfuturechangeinpopulationorrangesize.Unknown.
D3)Overlapofmodeledfuturerangewithcurrentrange.Unknown.
D4)Protectedareas.Neutral.Veryfewrivermilesareconsideredprotected,butwetlandsand
waterwaysreceivelegalprotectionthroughCleanWaterActandotherlegislation.
Literature Cited
Armstrong,D.M.,J.P.Fitzgeraldand,C.A.Meaney.2011.MammalsofColorado,2ndEdition.UniversityPressofColorado.
704pp.
Boyle,S.,andS.Owens.2007.NorthAmericanBeaver(CastorCanadensis):atechnicalconservationassessment.[Online].
USDAForestService,RockyMountainRegion.Available::
http://www.fs.fed.us/r2/projects/scp/assessments/northamericanbeaver.pdf[5January2015].
MacArthur,R.A.1989.Energymetabolismandthermoregulationofbeaver(Castorcanadensis).CanadianJournalof
Zoology67:651‐657.
MacArthur,R.A.,andA.P.Dyck.1990.Aquaticthermoregulationofcaptiveandfree‐rangingbeavers(Castorcanadensis).
CanadianJournalofZoology68:2409‐2416.
McNew,L.B.,Jr.,andA.Woolf.2008.Dispersalandsurvivalofjuvenilebeavers(Castorcanadensis)insouthernIllinois.
AmericanMidlandNaturalist154:217‐228.
Sun,L.,D.Müeller‐Schwarze,B.A.Schulte.2000.Dispersalpatternsandeffectivepopulationsizeofthebeaver.Canadian
JournalofZoology78:393‐398.
VanDeelen,T.R.,andD.H.Pletscher.1996.Dispersalcharacteristicsoftwo‐year‐oldbeavers,Castorcanadensis,inwestern
Montana.CanadianField‐Naturalist110:318‐321.

ClimateChangeVulnerabilityAssessmentforColoradoBLM297
Desert Bighorn Sheep
Oviscanadensisnelsoni
G4/S4
Family:Bovidae
Nophotoavailable
Climate Vulnerability Rank: Moderately Vulnerable
ThisColoradostate‐widerankisbasedon:transportationcorridorsthatcanlimitO.canadensis
nelsonidispersal;likelyincreaseindroughtconditionsthroughitsrange;geneticbottlenecks;and
modeledimpactsfromclimatechange.Despitethesethreats,O.canadensisnelsoniarewelladapted
todroughtconditions,havebroadrangesthatmayallowsomepopulationstomigrateawayfrom
inhospitablehabitatsandconditions,andhaveshownflexibilityintimingofparturitionthatmay
bettermatchperiodsofheightenedresourceavailability.
Distribution:O.canadensisnelsoniarefoundinwesternColoradoinafewspecificpopulations
neartheUtahborder.Habitat:canbefoundinavarietyofhabitats,butpreferareaswithhigh‐
visibilitywithgrass,lowshrubs,muchrockcoverandtopographicrelief,andwithabundantopen
areasforescape.Elevation:Varies,buttypicallylessthan10,000feet.
EcologicalSystem:Cliffs,grasslands
CCVI Scoring
B1)Exposuretosealevelrise.Neutral.
B2a)Distributionrelativetonaturalbarriers.Neutral.Thereissomedesertbighornsheep
habitatnorthofcurrentreintroductionsites(BlackRidge,Uncompahgre,andDoloresRiver
populations),butitisseparatedbylowerelevationvalleys.Givenbighornsheepabilitytoutilize
lowerelevationhabitats(KrausmanandBowyer2003),populationshavethepotentialtomigrate
northasclimateschange.
298ColoradoNaturalHeritageProgram©2015
B2b)Distributionrelativetoanthropogenicbarriers.IncreaseVulnerability.Urban,suburban,
andtransportationdevelopmentborderbighornsheeppopulationstothenorth.Thesemaybe
minimallyrestrictiveinsomeareas,butmajortransportationcorridorscanprohibitmovementand
restrictgeneflow(Eppsetal.2005).Additionally,becausehuntedbighornsheepshowagreater
responsetohumandisturbance(Geist1971,KingandWorkman1986)thisdevelopmentpressure
andthehumanpopulationsinproximitytoitmayfurtherprohibitmigration.Becauseitisunclearif
thepotentialisolationandsheepbehaviorareidenticaltothosedocumentedinCalifornia
populations,thisisconsidered“increasevulnerability”insteadof“greatlyincreasevulnerability”.
B3)Impactoflandusechangesresultingfromhumanresponsestoclimatechange.Neutral.
Neithersolar,wind,orbiomassenergyproductionappeartobehigh‐rewardtargetsforthisregion
ofwesternColoradobasedonNationalRenewalEnergymaps
(apps1.eere.energy.gov/states/maps.cfm/state=CO).
C1)Dispersalandmovements.DecreaseVulnerability.Bighornsheepcanmoveupto70km
betweenseasonalranges(Beechametal.2007).
C2ai)Predictedsensitivitytotemperature:historicalthermalniche.Neutral.Muchofthe
desertbighornrangeinColoradofallswithinthe55‐77°Frange.
C2aii)Predictedsensitivitytotemperature:physiologicalthermalniche.SomewhatDecrease
Vulnerability.Hottertemperaturesdonotappeartochallengebighornphysiology(Turner1973).
C2bi)Predictedsensitivitytochangesinprecipitation,hydrology,ormoistureregime:
historicalhydrologicalniche.SomewhatIncreaseVulnerability.BasedontheClimateWizardmap
ofhistorichydrologicvariation,muchofthedesertbighornsheeprangeinColoradovariesfromthe
lowestvariationtomid‐levelsofvariability.
C2bii)Predictedsensitivitytochangesinprecipitation,hydrology,ormoistureregime:
physiologicalhydrologicalniche.NeutraltoSomewhatDecrease.Desertbighornsheeparewell
adaptedtoheatanddroughtstress,evenabletoconcentrateurinebetterthancamels(Turner
1973).
C2c)Dependenceonaspecificdisturbanceregimelikelytobeimpactedbyclimatechange.
SomewhatIncrease.Desertbighornsheepareoccasionallyexposedtoandadaptedtodrought
conditions.However,therecenttrendsinwarminganddroughtmaybeimpactingviability.
Prolongeddroughtcancauseincreasedsheepmortality(Monson1960),impactrecruitment
(Wehausenetal.1987),andcontributetodecreasedpopulationviability(WeaverandMensch
1971).Climatedatasuggestthatdroughtwillpossiblyincreaseinfrequency,intensityandduration.
Diseaseisacommonfactorcausingperiodicdesertbighorndecline(Singeretal.2001).
C2d)Dependenceonsnow‐coveredhabitats.Neutral.Thereisnoknownrelationshipofthis
speciestosnoworice‐coveredhabitats.
ClimateChangeVulnerabilityAssessmentforColoradoBLM299
C3)Restrictiontouncommongeologicalfeaturesorderivatives.Neutral.Thisspeciesisnot
knowntospecializeonuncommongeologicalfeatures.
C4a)Dependenceonotherspeciestogeneratehabitat.Neutral.Norelianceonotherspeciesfor
habitatgeneration.
C4b)Dietaryversatility.Neutral.Desertbighornsheepareherbivorous,feedinglargelyon
grassesandforbs,supplementingthisdietwithsomeshrubs(Armstrongetal.2011).
C5a)Measuredgeneticvariation.Neutral.Geneticdiversityofdesertbighornpopulationsis
relativelyhighinsomepopulations(Gutierrez‐Espeletaetal.2000)whilelowinothers(Hedrick
andWehausen2014).
C5b)Occurrenceofbottlenecksinrecentevolutionaryhistory.SomewhatIncrease
VulnerabilitytoNeutral.Populationisolationandreintroductioneffortswithsmallpopulations
havecreatedgeneticbottlenecksinsomeregions(Rameyetal.2001,Hedricketal.2001).
C6)Phenologicalresponsetochangingseasonaltemperatureandprecipitationdynamics.
SomewhatDecreaseVulnerabilitytoNeutral.Desertbighornsheephaveshownsite‐specific
variabilityinparturitionthatallowsflexibilitytocapitalizingonavailableresources,butthismay
comewithfitnessconsequencesfornewlyreintroducedpopulations(Whitingetal.2011)
D1)Responsetorecentclimatechange.Neutral.Nothingreported.
D2)Modeledfuturechangeinpopulationorrangesize.SomewhatIncreaseVulnerability.Epps
etal.(2004)modeledthepotentialoffuturepopulationdeclineoverthenext60years.With
minimumtemperaturechangescenariosaverageextinctionprobabilityofpopulationswas20%.
Whencombinedwiththeprojecteddeclineinprecipitationtheprobabilityincreasedto30%.
D3)Overlapofmodeledfuturerangewithcurrentrange.Unknown.Nothingdocumented.
D4)Protectedareas.SomewhatIncreaseVulnerability.Withinthecurrentrangetherearefew
protectedareasthatwouldprotectpopulations.
Literature Cited
Armstrong,D.M.,J.P.Fitzgeraldand,C.A.Meaney.2011.MammalsofColorado,2ndEdition.UniversityPressofColorado.
704pp.
BeechamJr,J.J.,C.P.Collins,andT.D.Reynolds.2007.RockyMountainBighornSheep(OvisCanadensis):atechnical
conservationassessment.[Online].USDAForestService,RockyMountainRegion.Available:
http://www.fs.fed.us/r2/projects/scp/assessments/rockymountainbighornsheep.pdf[6January2015].
Epps,C.W.,D.R.McCullough,J.D.Wehausen,V.C.Bleich,andJ.L.Rechel.2004.Effectsofclimatechangeonpopulation
persistenceofdesert‐dwellingmountainsheepinCalifornia.ConservationBiology18:102‐113.
Epps,C.W.,P.J.Palsbell,J.D.Wehausen,G.K.Roderick,R.R.Ramey,andD.R.McCullough.2005.Highwaysblockgeneflow
andcausearapiddeclineingeneticdiversityofdesertbighornsheep.EcologyLetters8:1029‐1038.
300ColoradoNaturalHeritageProgram©2015
Geist,V.1971.Mountainsheep:astudyinbehaviorandevolution.UniversityofChicagoPress,Chicago,383pp.
Gutierrez‐Espeleta,G.A.,S.T.Kalinowski,W.M.Boyce,andP.W.Hedrick.2000.Geneticvariationandpopulationstructure
indesertbighornsheep:implicationsforconservation.ConservationGenetics1:3‐15.
Hedrick,P.W.,G.A.Gutierrez‐Espeleta,andR.N.Lee.2001.Foundereffectsinanislandpopulationofbighornsheep.
MolecularEcology10:851‐857.
Hedrick,P.W.,andJ.D.Wehausen.2014.Desertbighornsheep:changesingeneticvariationovertimeandtheimpactof
mergingpopulations.JournalofFishandWildlifeBiology5:3‐13.
King,M.M.,andG.W.Workman.1986.Responseofdesertbighornsheeptohumanharassment:managementimplications.
TransactionsoftheNorthAmericanWildlifeandNaturalResourcesConference51:74‐85.
Krausman,P.R.,andR.T.Bowyer.2003.Mountainsheep,OviscanadensisandO.dalli.Pp.1095‐1115inWildmammalsof
NorthAmerica:biology,management,andeconomics.2nded.(G.A.Feldhamer,B.C.Thompson,andJ.A.Chapman,eds.).
JohnHopkinsUniversityPress,Baltimore,MD.1216pp.
Monson,G.1960.Effectsofclimateondesertbighornnumbers.DesertBighornCouncilTransactions4:12‐14.
Ramey,R.R.,G.Luikart,andF.J.Singer.2001.Geneticbottlenecksresultingfromrestorationefforts:thecaseofthedesert
bighornsheepinBadlandsNationalPark.RestorationEcology8:85‐90.
Singer,F.J.,L.C.Zeigenfuss,andL.Spicer.2001.Roleofpatchsize,disease,andmovementinrapidextinctionofbighorn
sheep.ConservationBiology15:1347‐1354.
Turner,J.C.1973.Water,energyandelectrolytebalanceinthedesertbighornsheep,Oviscanadensis.PhDThesis.
UniversityofCalifornia,Riverside.138pp.
Weaver,R.A.,andJ.L.Mensch.1971.BighornsheepinnortheasternRiversideCounty.Wildlifemanagement
administrativereport71‐1.CaliforniaDepartmentofFishandGame,Sacramento,California.
Wehausen,J.D.,V.C.Bleich,B.Blong,andT.L.Russi.1987.RecruitmentdynamicsinasouthernCaliforniamountain
sheeppopulation.JournalofWildlifeManagement51:86‐98.
Whiting,J.C.,R.T.Bowden,J.T.Flinders,andD.L.Eggert.2011.Reintroductionbighornsheep:fitnessconsequencesof
adjustingparturitiontolocalenvironments.JournalofMammalogy92:213‐220.

ClimateChangeVulnerabilityAssessmentforColoradoBLM301
Fringed Myotis
Myotisthysanodes
G4/S3
Family:Vespertilionidae
Climate Vulnerability Rank: Not Vulnerable/Presumed Stable
ThisColoradostate‐widerankisbasedonthefollowingfactors:1)fewtonobarrierstomovement;
2)associationwithcavesandminesasgeologicfeaturesmaybeincreasevulnerabilityunder
projectedincreasesintemperatureduetoclimatechange,howeverthisspeciesisnotfound
exclusivelyincavesandmines.
Distribution:InColorado,Thefringedmyotisthisspecieshasbeenfoundsparinglyonboththe
easternandwesternsidesoftheContinentalDivide(Armstrongetal.2011).Habitat:InColorado,
thefringedmyotisisfoundinconiferouswoodlandsandshrublandssuchasponderosapine,
greasewood,oakbrush,andsaltbrush(Armstrongetal.2011).Elevation:Thisspecieshasbeen
recordedupto7,500feetinColorado(Armstrongetal.2011).
CCVI Scoring
B1)Exposuretosealevelrise.Neutral.
B2a)Distributionrelativetonaturalbarriers.Neutral.Volant–nobarriers
B2b)Distributionrelativetoanthropogenicbarriers.Neutral.Volant–nobarriers
B3)Impactoflandusechangesresultingfromhumanresponsestoclimatechange.Neutral.It
isunlikelythatanyclimatemitigation‐relatedlandusechangeswilloccurwithinthisspecies’range
withinColorado.
C1)Dispersalandmovements.Decrease.Long‐distancedispersalabilities.
302ColoradoNaturalHeritageProgram©2015
C2ai)Predictedsensitivitytotemperature:historicalthermalniche.Neutral.
C2aii)Predictedsensitivitytotemperature:physiologicalthermalniche.Neutral.
C2bi) Predictedsensitivitytochangesinprecipitation,hydrology,ormoistureregime:
historicalhydrologicalniche.Neutral.
C2bii)Predictedsensitivitytochangesinprecipitation,hydrology,ormoistureregime:
physiologicalhydrologicalniche.Somewhatincrease.AdamsandHayes(2008)postulatedthat
theimpactofreducedwaterstoragecapacityasaresultofclimatechangeinthearidwestern
UnitedStateswouldnegativelyimpactlactatingfemalesofthisspecies,especiallyatalocalscale.
C2c)Dependenceonaspecificdisturbanceregimelikelytobeimpactedbyclimatechange.
Neutral.
C2d)Dependenceonsnow‐coveredhabitats.Neutral.
C3)Restrictiontouncommongeologicalfeaturesorderivatives.SomewhatIncrease.Thisbat
isfoundincavesandmines,butinColoradoisnotrestrictedtothesefeatures.
C4a)Dependenceonotherspeciestogeneratehabitat.Neutral.
C4b)Dietaryversatility.Neutral. This species feeds broadly on moths, beetles, and other flying insects
(Keinath 2004; Armstrong et al. 2011).
C4c)Pollinatorversatility(Plantsonly,notapplicable).
C4d)Dependenceonotherspeciesforpropaguledispersal.Neutral.
C4e)Formspartofaninterspecificinteractionnotcoveredby4a‐d.Unknown.
C5a)Measuredgeneticvariation.Unknown.
C5b)Occurrenceofbottlenecksinrecentevolutionaryhistory.Unknown.
C6)Phenologicalresponsetochangingseasonaltemperatureandprecipitationdynamics.
Unknown.
D1)Responsetorecentclimatechange.Unknown.
D2)Modeledfuturechangeinpopulationorrangesize.Unknown.
D3)Overlapofmodeledfuturerangewithcurrentrange.Unknown.
D4)Protectedareas.Unknown.
ClimateChangeVulnerabilityAssessmentforColoradoBLM303
Literature Cited
Adams,R.A.andM.A.Hayes.2008.Wateravailabilityandsuccessfullactationbybatsasrelatedtoclimatechangeinarid
regionsofwesternNorthAmerica.JournalofAnimalEcology77:1115‐1121.
Armstrong,D.M.,J.P.Fitzgerald,andC.A.Meaney.2011.MammalsofColorado,2ndedition.DenverMuseumofNatureand
ScienceandUniversityPressofColorado,Boulder,CO.
Keinath,D.A.2004.Fringedmyotis(Myotisthysanodes):atechnicalconservationassessment.[Online].USDAForest
Service,RockyMountainRegion.Available:
http://www.fs.fed.us/r2/projects/scp/assessments/townsendsbigearedbat.pdf

304ColoradoNaturalHeritageProgram©2015
Gunnison Prairie Dog
Cynomysgunnisoni
G5/S5
Family:Sciuridae
Climate Vulnerability Rank: Not Vulnerable/Presumed Stable
DespiteC.gunnisonibeingrankedasStable,thefactorsthatwouldleadittobemorevulnerableare:
predicteddecreasesinprecipitation;habitatloss;prairiedogsusceptibilitytoplague:andlimited
geneticvariability.Currently,noneoftherankingfactorsconsiderthethreatshighenoughthatC.
gunnisoniwouldbeinimminentthreatfromon‐goingclimatechange.Thespeciesabilityto
disperseanditslackofrelianceofmesichabitatsbufferitfromclimatechangethreats.
Distribution:C.gunnisoniisfoundinsouthwesternandsouth‐centralColoradoingrasslands,and
semi‐desertandmontaneshrublands(Armstrongetal.2011).Habitat:C.gunnisoniarehabitat
architects,modifyingthesoilandvegetativecharacteristicsaroundcolonies.Theyinhabit
shortgrassandmid‐grassprairies,shrublandsinlowvalleys,andwetter,high‐elevationprairies.
Elevation:6000‐12000feet.
EcologicalSystem:Grasslands,Shrublands
CCVI Scoring
B1)Exposuretosealevelrise‐Neutral.
B2a)Distributionrelativetonaturalbarriers.NeutraltoSomewhatIncreaseVulnerability.
TherearevariouslowpassesinandoutofprairiedograngeinColoradothatwillnotpreventthe
GunnisonPrairiedogfromemigrating,butmaylimitdispersalifsubjectedtoclimate‐causedshifts.
Populationsareknowntohaveoccurredashighas~12,000’elevationinColorado(Armstronget
ClimateChangeVulnerabilityAssessmentforColoradoBLM305
al.2011).However,theUSFWS(2010)pointedoutthatnumerouspartsoftherangeareseparated
bymountainrangesthatalmostcompletelylimitprairiedogmovementbetweenthem.
B2b)Distributionrelativetoanthropogenicbarriers.Neutral.Muchoftheprairiedograngein
Coloradoisonpublicland.FutureplanningscenariosforSouthParksuggestincreasedsuburban
andinfrastructuredevelopmentthatmaylimitdispersalcapacityforpopulationsinthisregion.
Muchoftherangeisnothinderedbyanthropogenicdisturbancetogreatlylimitrangewideclimate‐
causeddispersal.
B3)Impactoflandusechangesresultingfromhumanresponsestoclimatechange.Neutralto
SomewhatIncreaseVulnerability.Wind‐energydevelopmentisincreasinginColorado.Alongthe
easternedgesoftheGunnisonandSanLuisvalleyswindspeedsareattractiveandmaytargetwind‐
energydevelopmentinthisareaoftheprairiedogsrange.Similarly,solarenergymaybetargeted
fortheSanLuisValleywheresolarexposureispromising(NaturalResourcesEnergyLaboratory,
ConcentratingSolarPowerEnergymapforColorado,2007andGlobalSolarRadiationatLatitude
TiltmapforColorado,2007).Itisunclearhowthisspeciesrespondstoenergydevelopment,butit
islikelysuchdevelopmentwouldfurthersegmentpopulations.
C1)Dispersalandmovements.SomewhatDecrease.Themovementsanddispersalarepoorly
studiedinthisspecies.However,inotherspeciesofprairiedogsmovementsareknowntobe
around2‐8km(GarrettandFranklin1988;Knowles1985).SeglundandSchnurr(2010)reported
dispersaldistancesaslongas7.7km.
C2ai)Predictedsensitivitytotemperature:historicalthermalniche.Neutral.Basedon
ClimateWizard.orgPastExposureTemperatureVariation,muchofGunnison’sprairiedograngein
Coloradoisfrom55‐77°F.
C2aii)Predictedsensitivitytotemperature:physiologicalthermalniche.NeutraltoSomewhat
IncreaseVulnerability.Becausethisspeciesofprairiedogisanobligatehibernator(Shalawayand
Slobodchikoff1988)itsoverwintersurvivalcanbechallengedifoverwinterthermalconditionsdo
notmaintainlong,stableperiodsofcoldtemperatures(Arnoldetal.1991,Schorretal.2009).Thus,
ifthermalconditionsarenotappropriateforhibernation,survivalmaybedepressed.
C2bi)Predictedsensitivitytochangesinprecipitation,hydrology,ormoistureregime:
historicalhydrologicalniche.SomewhatIncrease.BasedonClimateWizard.orgAverageAnnual
Precipitation1951‐2006,muchofGunnison’sprairiedograngeinColoradoismiddle‐to‐low
precipitationvariation.
C2bii)Predictedsensitivitytochangesinprecipitation,hydrology,ormoistureregime:
physiologicalhydrologicalniche.NeutraltoSomewhatDecrease.Gunnison’sprairiedogsinhabit
grasslandsandsemidesertandmontaneshrublands(Armstrongetal.2011).Vegetationconditions
ofmanylandswithintherangeofGunnison’sprairiedoghavebeenalteredthroughgrazing
(Fleischner1994).Theprairiedogsarepossiblymoresusceptibletostressfromdroughtwhere
nativevegetationhasbeenseverelyaltered(SeglundandSchnurr2010).Mostvegetationwithin
306ColoradoNaturalHeritageProgram©2015
usedhabitathassomeleveloftolerancetoaridconditionsandmaynotbedramaticallyimpacted
byincreaseddryingpredictedbyclimatemodeling.
C2c)Dependenceonaspecificdisturbanceregimelikelytobeimpactedbyclimatechange.
SomewhatIncreasetoIncrease.Themostdramaticandrecurringdisturbancethatcanimpact
Gunnison’sprairiedogsisplague(Cullyetal.1997).Gunnison’sprairiedogsareoccasionally
exposedtodroughtconditions.Theseconditionscausestressandevenpopulationreduction/local
extirpationintheblack‐tailedprairiedog(Fackaetal.2010).Climatedatasuggestthatdroughtwill
possiblyincreaseinfrequency,intensityandduration.
C2d)Dependenceonsnow‐coveredhabitats.Neutral.Thereisnoknownrelationshipofthis
speciestosnoworice‐coveredhabitats.
C3)Restrictiontouncommongeologicalfeaturesorderivatives.Neutral.Thisspeciesisnot
knowntospecializeonuncommongeologicalfeatures.
C4a)Dependenceonotherspeciestogeneratehabitat.Neutral.Generatesandmodifiesitsown
habitatbyburrowingandgrazing.
C4b)Dietaryversatility.Neutral.Gunnison’sprairiedogisanherbivore,feedinglargelyon
grassesandforbs,supplementingthisdietwithsomeshrubs(FitzgeraldandLechleitner1974;
Longhurst1944).
C5a)Measuredgeneticvariation.NeutraltoSomewhatIncreaseVulnerability.Geneticdiversity
inthisspecieswasdeterminedtobelow(Travisetal.1997).
C5b)Occurrenceofbottlenecksinrecentevolutionaryhistory.onlyif5Aisunknown.
C6)Phenologicalresponsetochangingseasonaltemperatureandprecipitationdynamics.
Neutral.Noobservationsmade.
D1)Responsetorecentclimatechange.Neutral.Nothingreported.
D2)Modeledfuturechangeinpopulationorrangesize.Unknown.
D3)Overlapofmodeledfuturerangewithcurrentrange.Unknown.
D4)Protectedareas.Neutral.
Literature Cited
Armstrong,D.M.,J.P.Fitzgeraldand,C.A.Meaney.2011.MammalsofColorado,2ndEdition.UniversityPressofColorado.
704pp.
Arnold,W.,G.Heldmaier,S.Ortmann,H.Pohl,T.Ruff,andS.Stenlechner.1991.Ambienttemperaturesinhibernaculaand
theirenergeticconsequencesforalpinemarmots(Marmotamarmota).JournalofThermalBiology16:223‐226.
ClimateChangeVulnerabilityAssessmentforColoradoBLM307
Cully,Jr.,J.F.,A.M.Barnes,T.J.Quan,andG.Maupin.1997.DynamicsofplagueinaGunnison’sprairiedogcolonycomplex
fromNewMexico.JournalofWildlifeDiseases33:706‐719.
Facka,A.N.,etal.2010.Droughtleadstocollapseofblack‐tailedprairiedogpopulationsreintroducedtotheChihuahuan
Desert.JournalofWildlifeManagement74:1252‐1762.
Fitzgerald,J.P.andR.R.Lechleitner.1974.ObservationsonthebiologyofGunnison’sprairiedogincentralColorado.J.
Colorado‐WyomingAcad.Sci.21:22.
Fleischner,T.L.1994.EcologicalcostsoflivestockgrazinginwesternNorthAmerica.ConservationBiology8:629‐644.
Garrett,M.G.,andW.L.Franklin.1988.Behavioralecologyofdispersalintheblack‐tailedprairiedog.Journalof
Mammalogy69:236‐250.
Knowles,C.J.1985.ObservationonprairiedogdispersalinMontana.PrairieNaturalist17:33‐40.
Longhurst,W.1944.ObservationsontheecologyoftheGunnisonprairiedoginColorado.JournalofMammalogy25:24‐
36.
Schorr,R.A.,P.M.Lukacs,andG.L.Florant.2009.Bodymassandwinterseverityaspredictorsofoverwintersurvivalin
Preble’smeadowjumpingmouse.JournalofMammalogy90:17‐24.
Seglund,A.E.andP.M.Schnurr.2010.ColoradoGunnison’sandwhite‐tailedprairiedogconservationstrategy.Colorado
DivisionofWildlife,Denver,Colorado,USA.
Shalaway,S.,andC.N.Slobodchikoff.1988.SeasonalchangesinthedietofGunnison’sprairiedog.JournalofMammalogy
69:835‐841.
Travis,S.E.,C.N.Slobodchikoff,andP.Keim.1997.DNAfingerprintingrevealslowgeneticdiversityinGunnison’sprairie
dog(Cynomysgunnisoni).JournalofMammalogy78:725‐732.
U.S.FishandWildlifeService.2010.SpeciesassessmentandlistingpriorityassignmentforCynomysgunnisoni(central
andsouth‐centralColorado,north‐centralNewMexico).Available:
http://ecos.fws.gov/docs/candidate/assessments/2010/r6/A0IB_V01.pdf

308ColoradoNaturalHeritageProgram©2015
Townsend’s Big‐eared Bat
Corynorhinustownsendiipallescens
G3G4T3T4/S2
Family:Vespertilionidae
Climate Vulnerability Rank: Not Vulnerable/Presumed Stable
ThisColoradostate‐widerankisbasedonthefollowingfactors:1)fewtonobarrierstomovement;
2)associationwithcavesandminesasgeologicfeaturesmaybeincreasevulnerabilityunder
projectedincreasesintemperatureduetoclimatechange.
Distribution:InColorado,Townsend’sbig‐earedbatoccursthroughoutthewesterntwo‐thirdsof
thestate,includingthesoutheasterncanyonlands(Armstrongetal.2011).Habitat:InColorado,
Townsend’sbig‐earedbatsoccurinawiderangeofhabitatsincludingsemi‐desertshrublands,
pinyon‐juniperwoodlands,anddryconiferousforests(Armstrongetal.2011).Itismostoften
foundroostingincavesandmines,butusesbuildings,crevices,andclifffacesduringthesummer
(Armstrongetal.2011).Elevation:Thisspecieshasbeenrecordedupto9,500feetinColorado
(Armstrongetal.2011).
CCVI Scoring
B1)Exposuretosealevelrise.Neutral.
B2a)Distributionrelativetonaturalbarriers.Neutral.Volant–nobarriers
B2b)Distributionrelativetoanthropogenicbarriers.Neutral.Volant–nobarriers
B3)Impactoflandusechangesresultingfromhumanresponsestoclimatechange.Neutral.It
isunlikelythatanyclimatemitigation‐relatedlandusechangeswilloccurwithinthisspecies’range
withinColorado.
ClimateChangeVulnerabilityAssessmentforColoradoBLM309
C1)Dispersalandmovements.Decrease.Long‐distancedispersalabilities.
C2ai)Predictedsensitivitytotemperature:historicalthermalniche.Neutral.
C2aii)Predictedsensitivitytotemperature:physiologicalthermalniche.Neutral.
C2bi)Predictedsensitivitytochangesinprecipitation,hydrology,ormoistureregime:
historicalhydrologicalniche.Neutral.
C2bii)Predictedsensitivitytochangesinprecipitation,hydrology,ormoistureregime:
physiologicalhydrologicalniche.Neutral/Somewhatincrease.AdamsandHayes(2008)
postulatedthattheimpactofreducedwaterstoragecapacityasaresultofclimatechangeinthe
aridwesternUnitedStateswouldnegativelyimpactlactatingfemalesofMyotisthysanodes,
especiallyatalocalscale.ThisproposedimpactcouldaffectotherspeciessuchasCorynorhinus
townsendiiaswell.
C2c)Dependenceonaspecificdisturbanceregimelikelytobeimpactedbyclimatechange.
Neutral.
C2d)Dependenceonsnow‐coveredhabitats.Neutral.
C3)Restrictiontouncommongeologicalfeaturesorderivatives.SomewhatIncrease.Thisbat
isacaveandmineobligate,butinColoradoisfoundinminesmorefrequentlythancaves.
C4a)Dependenceonotherspeciestogeneratehabitat.Neutral.
C4b)Dietaryversatility.Neutral.Thisspeciesisamothspecialist,butwillfeedopportunistically
onotherflyinginsects(GruverandKeinath2006).
C4c)Pollinatorversatility(Plantsonly,notapplicable).
C4d)Dependenceonotherspeciesforpropaguledispersal.Neutral.
C4e)Formspartofaninterspecificinteractionnotcoveredby4a‐d.Unknown.
C5a)Measuredgeneticvariation.NeutraltoSomewhatDecrease.Inananalysisofgenetic
diversityamongsubspeciesofC.townsendii,Piaggioetal.(2009)foundthatC.t.pallescenshada
levelofdiversitysimilartoC.t.townsendiiandbothofthesesubspecieshadagreaterlevelof
diversitythantheendangeredC.t.virginianusasmeasuredbytheaveragenumberofallelesper
locusandaverageallelicrichnessperpopulation.
C5b)Occurrenceofbottlenecksinrecentevolutionaryhistory.Unknown.
C6)Phenologicalresponsetochangingseasonaltemperatureandprecipitationdynamics.
Unknown.
D1)Responsetorecentclimatechange.Unknown.
310ColoradoNaturalHeritageProgram©2015
D2)Modeledfuturechangeinpopulationorrangesize.Unknown.
D3)Overlapofmodeledfuturerangewithcurrentrange.Unknown.
D4)Protectedareas.Unknown.
Literature Cited
Adams,R.A.andM.A.Hayes.2008.Wateravailabilityandsuccessfullactationbybatsasrelatedtoclimatechangeinarid
regionsofwesternNorthAmerica.JournalofAnimalEcology77:1115‐1121.
Armstrong,D.M.,J.P.Fitzgerald,andC.A.Meaney.2011.MammalsofColorado,2ndedition.DenverMuseumofNatureand
ScienceandUniversityPressofColorado,Boulder,CO.
Gruver,J.C.,andD.A.Keinath.2006.Townsend’sBig‐earedBat(Corynorhinustownsendii):atechnicalconservation
assessment.[Online].USDAForestService,RockyMountainRegion.Available:
http://www.fs.fed.us/r2/projects/scp/assessments/townsendsbigearedbat.pdf
Piaggio,A.J.,K.W.Navo,andC.W.Stihler.2009.Intraspecificcomparisonofpopulationstructure,geneticdiversity,and
dispersalamongthreesubspeciesofTownsend'sbig‐earedbats,Corynorhinustownsendiitownsendii,C.t.pallescens,and
theendangeredC.t.virginianus.ConservationGenetics10:143‐159.

ClimateChangeVulnerabilityAssessmentforColoradoBLM311
White‐tailed Prairie Dog
Cynomysleucurus
G4/S4
Family:Sciuridae
Climate Vulnerability Rank: Not Vulnerable/Presumed Stable
SimilartoC.gunnisoni,C.leucurusisconsideredStable,butthefactorsthatwouldleadittobemore
vulnerableare:predicteddecreasesinprecipitation;necessityforcoldenvironsforhibernation;
habitatloss;prairiedogsusceptibilitytoplague:andlimitedgeneticvariability.Currently,noneof
therankingfactorsconsiderthethreatshighenoughthatC.leucuruswouldbeinimminentthreat
fromon‐goingclimatechange.Thespeciesabilitytodisperseanditslackofrelianceofmesic
habitatsbufferitfromclimatechangethreats.
Distribution:C.leucurusisfoundinnorthwestandwest‐centralColoradoinsemi‐aridgrasslands
andshrublands,andmountainvalleys(Armstrongetal.2011).Habitat:C.leucurusaremoreoften
foundinsemidesertshrublands,butoccasionallyinvadingpasturesandagriculturallandsatlower
elevations(Armstrongetal.2011).Elevation:typicallybelow8,500ft.
EcologicalSystem:Grasslands,Shrublands
CCVI Scoring
B1)Exposuretosealevelrise.Neutral.
B2a)Distributionrelativetonaturalbarriers.Neutral.Therearenoobviousnaturalbarriersto
white‐tailedprairiedogmovementinColorado.Populationsareknowntohaveoccurredashighas
~10,000’elevationinColorado(Armstrongetal.2011).
312ColoradoNaturalHeritageProgram©2015
B2b)Distributionrelativetoanthropogenicbarriers.Neutral.Muchoftheprairiedograngein
Coloradoisonpubliclandandmuchoftherangeisnothinderedbyanthropogenicdisturbanceto
greatlylimitrangewideclimate‐causeddispersal.
B3)Impactoflandusechangesresultingfromhumanresponsestoclimatechange.Neutral.
Wind‐energydevelopmentisincreasinginColorado.InnorthwesternColoradowindspeedsmaybe
attractiveforwind‐energydevelopmentinthisareaoftheprairiedogsrange.However,itis
unlikelythatdevelopmentwillsignificantlyimpactbymitigation‐relatedlandusechanges.
C1)Dispersalandmovements.SomewhatDecrease.Maximummovementdistancesdocumented
forwhite‐tailedprairiedogsis8km(Cooke1993,citedinSeglundetal.2006),butmost
documentedmovementsarelessthanthis.
C2ai)Predictedsensitivitytotemperature:historicalthermalniche.Neutral.Basedon
ClimateWizard.orgPastExposureTemperatureVariation,muchofwhite‐tailedprairiedograngein
Coloradoisfrom55‐77°F.
C2aii)Predictedsensitivitytotemperature:physiologicalthermalniche.NeutraltoSomewhat
IncreaseVulnerability.Becausethisspeciesofprairiedogisanobligatehibernator(Harlow1995)
itsoverwintersurvivalcanbechallengedifoverwinterthermalconditionsdonotmaintainlong,
stableperiodsofcoldtemperatures(Arnoldetal.1991,Schorretal.2009).Thus,ifthermal
conditionsarenotappropriateforhibernation,survivalmaybedepressed.
C2bi)Predictedsensitivitytochangesinprecipitation,hydrology,ormoistureregime:
historicalhydrologicalniche.SomewhatIncrease.BasedonClimateWizard.orgAverageAnnual
Precipitation1951‐2006,muchofwhite‐tailedprairiedograngeinColoradoismiddle‐to‐low
precipitationvariation.
C2bii)Predictedsensitivitytochangesinprecipitation,hydrology,ormoistureregime:
physiologicalhydrologicalniche..NeutraltoSomewhatDecrease.White‐tailedprairiedogs
inhabitaridgrasslandsandshrublandsinColorado(Armstrongetal.2011).Mostvegetationwithin
usedhabitathassomeleveloftolerancetoaridconditionsandmaynotbedramaticallyimpacted
byincreaseddryingpredictedbyclimatemodeling.
C2c)Dependenceonaspecificdisturbanceregimelikelytobeimpactedbyclimatechange.
SomewhatIncreasetoIncrease.Themostdramaticandrecurringdisturbancethatcanimpact
white‐tailedprairiedogsisplague(MenkensandAnderson1991).White‐tailedprairiedogsare
occasionallyexposedtodroughtconditions.Theseconditionscausestressandevenpopulation
reduction/localextirpationintheblack‐tailedprairiedog(Fackaetal.2010).Climatedatasuggest
thatdroughtwillpossiblyincreaseinfrequency,intensityandduration.
C2d)Dependenceonsnow‐coveredhabitats.Neutral.Thereisnoknownrelationshipofthis
speciestosnoworice‐coveredhabitats.
C3)Restrictiontouncommongeologicalfeaturesorderivatives.Neutral.Thisspeciesisnot
knowntospecializeonuncommongeologicalfeatures.
ClimateChangeVulnerabilityAssessmentforColoradoBLM313
C4a)Dependenceonotherspeciestogeneratehabitat.Neutral.Generatesandmodifiesitsown
habitatbyburrowingandgrazing.
C4b)Dietaryversatility.Neutral.White‐tailedprairiedogslargelyfeedongrassesandforbs,
supplementingthisdietwithsomeshrubs(Armstrongetal.2011).
C5a)Measuredgeneticvariation.NeutraltoSomewhatIncreaseVulnerability.Geneticdiversity
inthisspecieswasdeterminedtobelowcomparetoblack‐tailedprairiedogs(Cooke1993,citedin
Seglundetal.2006).
C5b)Occurrenceofbottlenecksinrecentevolutionaryhistory.Onlyif5Aisunknown.
C6)Phenologicalresponsetochangingseasonaltemperatureandprecipitationdynamics.
Unknown.Noobservationsmade.
D1)Responsetorecentclimatechange.Unknown.Nothingreported.
D2)Modeledfuturechangeinpopulationorrangesize.Unknown.
D3)Overlapofmodeledfuturerangewithcurrentrange.Unknown.
D4)Protectedareas.Neutral.
Literature Cited
Armstrong,D.M.,J.P.Fitzgeraldand,C.A.Meaney.2011.MammalsofColorado,2ndEdition.UniversityPressofColorado.
704pp.
Arnold,W.,G.Heldmaier,S.Ortmann,H.Pohl,T.Ruff,andS.Stenlechner.1991.Ambienttemperaturesinhibernaculaand
theirenergeticconsequencesforalpinemarmots(Marmotamarmota).JournalofThermalBiology16:223‐226.
Cooke,L.1993.TheroleoflifehistorytraitsintheevolutionofsocialityintheWTPD(Cynomysleucurus).Finalreportto
ArapahoNationalWildlifeRefuge,Walden,CO.CollegeoftheHolyCross,Worchester,MA.
Facka,A.N.,etal.2010.Droughtleadstocollapseofblack‐tailedprairiedogpopulationsreintroducedtotheChihuahuan
Desert.JournalofWildlifeManagement74:1252‐1762.
Harlow,H.J.1995.Fastingbiochemistryofrepresentativespontaneousandfacultativehibernators:thewhite‐tailed
prairiedogandtheblack‐tailedprairiedog.PhysiologicalZoology68:915‐934.
Menkens,Jr.,G.E.,andS.H.Anderson.1991.Populationdynamicsofwhite‐tailedprairiedogsduringanepizooticof
sylvaticplague.JournalofMammalogy72:328‐331.
Schorr,R.A.,P.M.Lukacs,andG.L.Florant.2009.Bodymassandwinterseverityaspredictorsofoverwintersurvivalin
Preble’smeadowjumpingmouse.JournalofMammalogy90:17‐24.
Seglund,A.E.,A.E.Ernst,M.Grenier,B.Luce,A.Puchniak,andP.Schnurr.2006.White‐tailedprairiedogconservation
assessment.WesternAssociationofFishandWildlifeAgencies,Laramie,WY.136pp.

314ColoradoNaturalHeritageProgram©2015
Desert Spiny Lizard
Sceloporusmagister
G5/S2
Family:Phrynosomatidae
Climate Vulnerability Rank: Not Vulnerable/Presumed Stable
ThisColoradostatewiderankisbasedon:theDesertspinylizardspreferenceforwarm
temperaturescoupledwiththeincreasingtemperaturesprojectedunderclimatechange,a
thermoregulatoryrangeof27⁰to37⁰C(Brattstrom1965)whichshouldallowthelizardtocope
withrisingtemperatures,thelizard’spreferenceforaridandhotlandscapesthatareactually
expectedtoincreaseinsizewithintheassessedareaduetoincreaseddroughtandtemperatures
projectedunderclimatechange,anda20percentexpansionintherangeofthelizardinthe
assessedareaasaresultofclimatechange(Buckley2010).Climatemodelsprojectincreased
warminganddroughtacrosstheassessedareawithannualaveragetemperaturesrisingby2.5°Fto
5.5°Fby2041‐2070andby5.5°Fto9.5°Fby2070‐2099withcontinuedgrowthinglobalemissions
(A2emissionsscenario),withthegreatestincreasesinthesummerandfall(Melilloetal.2014).
Distribution:InColorado,thislizardoccursintheextremesouthwesterncorneroftheStateat
elevationsbelow5,100feet(Hammerson1999).Habitat:ThehabitatinColoradoincludesshrub‐
covereddirtbanksandsparselyvegetatedrockyareasnearflowingstreamsandarroyos.They
prefersoftsoilsbeneathgreasewood,rabbitbrush,saltcedar,andothershrubsandfrequently
perchonlargerocksorinshrubsandtrees(Hammerson1999).
CCVI Scoring
B1)Exposuretosealevelrise.Neutral.
B2a)Distributionrelativetonaturalbarriers.Neutral.Largeriversandlakesactaseffective
barriersforthisspeciesasdootherwaterobstructionssuchaspondsandmarshes(NatureServe
ClimateChangeVulnerabilityAssessmentforColoradoBLM315
2014),butsmallerwaterobstacleswouldnotimpedelargescalemigratorymovementslikeshifts
indistributionduetoachangingclimate.However,therearenolargeriversorwaterbodieswithin
theassessmentareathatwouldpreventlargescalemovementsoftheDesertspinylizard.
B2b)Distributionrelativetoanthropogenicbarriers.Neutral.Busyhighways,highwayswith
obstructions,andurbanareascanactasbarrierstodispersal(NatureServe2014),butinthe
assessmentareatherearenolarge,busyhighwaysorlargeurbancenters,rathertherearefew
roadsandsmallhumanpopulations.
B3)Impactoflandusechangesresultingfromhumanresponsestoclimatechange.Neutral.
Changesinlanduseassociatedwithclimatechangearenotconsideredathreat.
C1)Dispersalandmovements.Neutral.Desertspinylizardjuvenileswilldisperseseveral100
metersfromtheirnatalareabeforeestablishingaterritoryoftheirown(TannerandKrogh1973)
C2ai)Predictedsensitivitytotemperature:historicalthermalniche.Neutral.Therange
occupiedbytheDesertspinylizardintheassessedareahasexperiencedanaverage(51.7‐77°
F/31.8‐43.0°C)zonalmeanseasonaltemperatureoverthelast50years.
C2aii)Predictedsensitivitytotemperature:physiologicalthermalniche.Somewhatdecrease.
TheDesertspinylizardprefersratherwarmtemperatures,attemptingtothermoregulatesuchthat
ithasameanbodytemperatureofabout35⁰C(range27⁰to37⁰C)(Brattstrom1965).
C2bi)Predictedsensitivitytochangesinprecipitation,hydrology,ormoistureregime:
historicalhydrologicalniche.Increase.TherangeoccupiedbytheDesertspinylizardinthe
assessedareahasexperiencedaverage(4‐10inches/100‐254mm)precipitationvariationinthe
past50years.
C2bii)Predictedsensitivitytochangesinprecipitation,hydrology,ormoistureregime:
physiologicalhydrologicalniche.Neutraltosomewhatdecrease.TheDesertspinylizardis
adaptedtoaridlandscapesinhabitingareasreceivinglessthan30centimetersofrainperyear(Vitt
andOhmart1974)andwiththeincreasedprojectionsfordroughtduetoclimatechangeinthe
assessmentarea(Melilloetal.2014),changingclimatecouldevenbenefitthespecies.
C2c)Dependenceonaspecificdisturbanceregimelikelytobeimpactedbyclimatechange.
Neutral.TheDesertspinylizardisnotdependentuponspecificdisturbanceregimessuchasfires,
floods,severewinds,pathogenoutbreaks,orsimilarevents.
C2d)Dependenceonsnow‐coveredhabitats.Neutral.TheDesertspinylizardisnotdependent
onhabitatswithice,snow,oronsnowpack.
C3)Restrictiontouncommongeologicalfeaturesorderivatives.Somewhatincrease.Desert
spinylizardsarerestrictedtosparselyvegetatedrockyareasnearflowingstreamsorarroyos
withintheassessmentarea(Hammerson1999).Suchareas,althoughnothighlyuncommonwithin
theassessmentarea,arecertainlynotadominantlandscapetype
316ColoradoNaturalHeritageProgram©2015
C4a)Dependenceonotherspeciestogeneratehabitat.Neutral.TheDesertspinylizardisnot
dependentonanyotherspeciestocreatesuitablehabitatforitsexistence.
C4b)Dietaryversatility.Neutral.Desertspinylizardsareopportunisticpredatorswithaflexible
diet,feedingmainlyonavarietyofinsectswithsomesmalllizardsandplantmaterialalsotaken
(Hammerson1999).
C4d)Dependenceonotherspeciesforpropaguledispersal.Neutral.TheDesertspinylizardisa
self‐disperser.
C4e)Formspartofaninterspecificinteractionnotcoveredby4a‐d.Neutral.Noother
interspecificinteractionsareimportanttothepersistenceoftheDesertspinylizard.
C5a)Measuredgeneticvariation.Neutral.ThegeneticvariationoftheDesertspinylizardis
aboutaverage,whencomparedtorelatedtaxa(Woodetal.2013).
C5b)Occurrenceofbottlenecksinrecentevolutionaryhistory.Unknown.
C6)Phenologicalresponsetochangingseasonaltemperatureandprecipitationdynamics.
Unknown.
D1)Responsetorecentclimatechange.Unknown.
D2)Modeledfuturechangeinpopulationorrangesize.Somewhatdecrease.Thepredicted
futurerangeoftheDesertspinylizardisexpectedtoincreasewithintheassessmentareabymore
than20percent(Buckley2010).
D3)Overlapofmodeledfuturerangewithcurrentrange.Unknown.
D4)Protectedareas.Unknown.
Literature Cited
Brattstrom,B.H.1965.BodyTemperaturesofReptiles.AmericanMidlandNaturalist73:376‐422.
Buckley,L.B.2010.Therangeimplicationsoflizardtraitsinchangingenvironments.GlobalEcologyandBiogeography,
19:452‐464.
Hammerson,G.A.1999.AmphibiansandreptilesinColorado.2nded.UniversityPressofColorado,Boulder,Colorado.364
pp.
Melillo,J.M.,T.C.Richmond,andG.W.Yohe,Eds.,2014:ClimateChangeImpactsintheUnitedStates:TheThirdNational
ClimateAssessment.U.S.GlobalChangeResearchProgram,841pp.doi:10.7930/J0Z31WJ2.
NatureServe.2014.NatureServeExplorer:Anonlineencyclopediaoflife[webapplication].Version7.1.NatureServe,
Arlington,Virginia.Availablehttp://explorer.natureserve.org.(Accessed:February17,2015).
Tanner,W.W.andJ.E.Krogh.1973.EcologyofSceloporusmagisterataNevadatestsite,NyeCounty,Nebraska.Great
BasinNaturalist,33:133‐146.
ClimateChangeVulnerabilityAssessmentforColoradoBLM317
Vitt,L.J.andR.D.Ohmart.1974.ReproductionandEcologyofaColoradoRiverPopulationofSceloporusmagister(Sauria:
Iguanidae).Herpetologica,30:410‐417.
Wood,D.A.,A.G.Vandergast,K.R.Barr,R.D.Inman,T.C.Esque,K.E.NussearandR.N.Fisher.2013.Comparative
phylogeographyrevealsdeeplineagesandregionalevolutionaryhotspotsintheMojaveandSonoranDeserts.Diversity
andDistributions,19:722–737

318ColoradoNaturalHeritageProgram©2015
Longnose Leopard Lizard
Gambeliawislizenii
G5/S1
Family:Crotaphytidae
Climate Vulnerability Rank: Not Vulnerable/Presumed Stable
ThisColoradostate‐widerankisbasedon:G.wislizeniirestrictedtoanareaofColoradothathas
seenlittletemperatureandhydrologicvariabilityandtheirsusceptibilitytohabitatlossfrom
encroachingweedygrasses.However,G.wislizeniiiswell‐adaptedtodroughtstress.
Distribution:G.wislizeniiisattheeasternlimitofitsrangeinwesternandsouthwesternColorado.
Habitat:G.wislizeniicanbefoundinflat,aridandsemiaridplainsandcanyonlandswithvarious
desertshrubs,includingsagebrush,greasewood,saltbush,andjunipers.Elevation:below6,000
feet.
EcologicalSystem:Xericshrublandswithmuchbareground.
CCVI Scoring
B1)Exposuretosealevelrise.Neutral.
B2a)Distributionrelativetonaturalbarriers.SomewhatIncreaseVulnerabilitytoNeutral.
Areasofexcessivegrasscovercanprohibitlizarduse(Schorretal.2011),butitisuncleartowhat
degreesuchexpansesofgrassexistaroundhabitatsinColorado.However,somepopulationsin
westernColoradoareborderedtothenorthbylargeriversthatmaybeunpassable.
B2b)Distributionrelativetoanthropogenicbarriers.Neutral.Therearefewknownhuman
barrierstodispersalwherelizardsarefound.
ClimateChangeVulnerabilityAssessmentforColoradoBLM319
B3)Impactoflandusechangesresultingfromhumanresponsestoclimatechange.Neutral.
Neithersolar,wind,orbiomassenergyproductionappeartobehigh‐rewardtargetsforthisregion
ofwesternColoradobasedonNationalRenewalEnergymaps
(apps1.eere.energy.gov/states/maps.cfm/state=CO).
C1)Dispersalandmovements.Neutral.Individualscanmoveupto1.5km(ParkerandPianka
1976,SchorrandLambert2010).
C2ai)Predictedsensitivitytotemperature:historicalthermalniche.Neutral.Muchofthe
desertbighornrangeinColoradofallswithinthe55‐77°Frange.
C2aii)Predictedsensitivitytotemperature:physiologicalthermalniche.SomewhatDecrease
Vulnerability.Hottertemperaturesdonotappeartochallengelizardphysiology.InColorado,mean
soilsurfacetemperatureswherelizardswerefoundwas100°F(SchorrandLambert2010).
C2bi)Predictedsensitivitytochangesinprecipitation,hydrology,ormoistureregime:
historicalhydrologicalniche.IncreaseVulnerability.BasedontheClimateWizardmapofhistoric
hydrologicvariation,muchoftheleopardlizardrangeinColoradoininthelowervariabilityrange.
C2bii)Predictedsensitivitytochangesinprecipitation,hydrology,ormoistureregime:
physiologicalhydrologicalniche.NeutraltoSomewhatDecrease.Leopardlizardsareadaptedto
heatanddroughtstress.
C2c)Dependenceonaspecificdisturbanceregimelikelytobeimpactedbyclimatechange.
NeutraltoSomewhatIncreaseVulnerability.Leopardlizardsarenotdependentonparticular
disturbanceregimes.However,undisturbedhabitatswithintheirrangeappeartopreventexpanse
ofinvasivegrasses(Westobyetal.1989,Hammerson1999).
C2d)Dependenceonsnow‐coveredhabitats.Neutral.Thereisnoknownrelationshipofthis
speciestosnoworice‐coveredhabitats.
C3)Restrictiontouncommongeologicalfeaturesorderivatives.Neutral.Thisspeciesisnot
knowntospecializeonuncommongeologicalfeatures.
C4a)Dependenceonotherspeciestogeneratehabitat.Neutral.Thisspeciesdoesnotrelyon
otherspeciesofhabitatdevelopment.
C4b)Dietaryversatility.Neutral.Leopardlizardsfeedonavarietyofinsectsandsome
vertebrates(Hammerson1999).
C5a)Measuredgeneticvariation.Neutral.Therearenodataonthegeneticvariabilityofthis
species.
C5b)Occurrenceofbottlenecksinrecentevolutionaryhistory.onlyif5Aisunknown.
C6)Phenologicalresponsetochangingseasonaltemperatureandprecipitationdynamics.
Neutral.Therearenodataonseasonaldynamics.
320ColoradoNaturalHeritageProgram©2015
D1)Responsetorecentclimatechange.Neutral.Nothingreported.
D2)Modeledfuturechangeinpopulationorrangesize.Unknown.
D3)Overlapofmodeledfuturerangewithcurrentrange.Unknown.
D4)Protectedareas.Neutral.ThesouthwesternColoradopopulationsexistwithinanational
monument,whilethecentral‐westernColoradopopulationsarewithinunprotectedfederallands.
Literature Cited
Hammerson,G.A.1999.AmphibiansandreptilesinColorado.2nded.UniversityPressofColorado,Boulder,Colorado.364
pp.
Parker,W.S.,andE.R.Pianka.1976.Ecologicalobservationsontheleopardlizard(Crotaphytuswislizenii)indifferent
partsofitsrange.Herpetologica32:95‐114.
Schorr,R.A.,andB.Lambert.2010.Longnoseleopardlizard(Gambeliawislizenii)homerangeandhabitatuseon
CannonballMesa,Colorado.ColoradoNaturalProgramReport.17pp.
Schorr,R.A.,B.A.Lambert,andE.Freels.2011.Habitatuseandhomerangeoflong‐nosedleopardlizards(Gambelia
wislizenii)inCanyonsoftheAncientsNationalMonument,Colorado.HerpetologicalConservationandBiology6:312‐323.
Westoby,M.,B.Walker,andI.Noy‐Meir.1989.Opportunisticmanagementforrangelandsnotatequilibrium.Journalof
RangeManagement42:266‐274.

ClimateChangeVulnerabilityAssessmentforColoradoBLM321
Midget Faded Rattlesnake
Crotalusoreganusconcolor
G5T4/S3?
Family:Viperidae
Climate Vulnerability Rank: Highly Vulnerable
ThisColoradostatewiderankisbasedon:theMidgetfadedrattlesnakesrelianceonrockoutcrops
suitablefordenningandthenarrowtemperaturerangessuitableforhibernatingrattlesnakesat
thosedens,barrierstomovementcreatedbylargeriverswithintheassessedarea,fragmentationof
theassessedareabybothpavedandunpavedroadsthatsignificantlyimpairmovement,thelowto
moderategeneticvariabilityofthesnakelesseningtheadaptabilityofthesnaketoclimatechange,
andtheincreaseintemperaturesprojectedfortheassessedareaduetoclimatechange.Climate
modelsprojectincreasedwarminganddroughtacrosstheassessedareawithannualaverage
temperaturesrisingby2.5°Fto5.5°Fby2041‐2070andby5.5°Fto9.5°Fby2070‐2099with
continuedgrowthinglobalemissions(A2emissionsscenario),withthegreatestincreasesinthe
summerandfall(Melilloetal.2014).
Distribution:Coloradoisattheeasternmarginofthesubspecies'range.InColorado,itoccursin
westcentralColoradoinMesa,Delta,Garfield,Montrose,andSanMiguelcounties(CNHP1998).
Habitat:Midgetfadedrattlesnakesoccurininawidevarietyofterrestrialhabitatsincluding
pinyon‐juniperwoodlands,plainsgrasslands,anddesertandmountainshrublands.Theytendto
preferaridtosemi‐aridsitesandtypicallyavoidwetsites.Theywilloccupysiteswithawiderange
ofsoiltypesfromsandytorocky(Hammerson1999).
CCVI Scoring
B1)Exposuretosealevelrise.Neutral.
B2a)Distributionrelativetonaturalbarriers.SomewhatIncreasetoneutral.Large,fastflowing
riversareabarriertothisrattlesnake,riversliketheYampa,Colorado,andothersthatoccurwithin
322ColoradoNaturalHeritageProgram©2015
theassessedareashouldbeconsideredbarriers(ReedandDouglas2002).Theseriverswillimpede
distributionalshiftsintheassessmentarea,butwillnotgreatlyorcompletelyimpairdistributional
shiftscausedbyclimatechange.Busyhighways,likeInterstate70thatbisectsthedistributionof
therattlesnakeintheassessedarea,alsoimpedemovements,butdonotcompletelyrestrict
movements(NatureServe2014).
B2b)Distributionrelativetoanthropogenicbarriers.Increase.Somewhatincreasetoneutral.
Roads(bothpavedandunpaved)restrictfine‐scalemovementpatternsoftheMidgetfaded
rattlesnakebutnotbroadscalemovements(Spearetal.2011)anddenselyurbanizedareas
dominatedbybuildingsandpavementaresufficientbarrierstomovementfortherattlesnake
(NatureServe2014).TheonlylargecityintheassessmentareaisGrandJunctionandthissingle
urbancentershouldnotsignificantlyimpedetherattlesnake’sabilitytoshiftitsdistributionwithin
theareainresponsetoclimatechange.
B3)Impactoflandusechangesresultingfromhumanresponsestoclimatechange.Increase.
Neutral.Changesinlanduseassociatedwithclimatechangearenotconsideredathreat.
C1)Dispersalandmovements.Somewhatdecreasetoneutral.Midgetfadedrattlesnakesare
dependentuponwinterdensandmigratetoandfromthosedensonanannualbasis.Althoughthey
havesomeofthelargestactivityrangesreportedinrattlesnakes,annualmovementsstillonly
movementsaveragearound2000metersperyear,only300metersforgravidfemales(Parkerand
Anderson2007).
C2ai)Predictedsensitivitytotemperature:historicalthermalniche.Neutral.Therange
occupiedbytheMidgetfadedrattlesnakeintheassessedareahasexperiencedanaverage(51.7‐
77°F/31.8‐43.0°C)zonalmeanseasonaltemperatureoverthelast50years.
C2aii)Predictedsensitivitytotemperature:physiologicalthermalniche.Increase.TheMidget
fadedrattlesnakeisrestrictedtorockoutcropswheretheirhibernaculaarelocated.Modelingof
denninghabitatindicatesaverynarrowtemperaturerangethatrepresentssuitabilityfor
rattlesnakedenning(Spearetal.2011)suggestingthatincreasingtemperaturesprojectedforthe
assessmentarea(Melilloetal.2014)couldnegativelyimpactcurrentlysuitabledenninghabitat,
influencingthefuturedistributionoftheMidgetfadedrattlesnake.
C2bi)Predictedsensitivitytochangesinprecipitation,hydrology,ormoistureregime:
historicalhydrologicalniche.Neutral.TherangeoccupiedbytheMidgetfadedrattlesnakeinthe
assessedareahasexperiencedaverage(21‐40inches/509‐1,016mm)precipitationvariationin
thepast50years.
C2bii)Predictedsensitivitytochangesinprecipitation,hydrology,ormoistureregime:
physiologicalhydrologicalniche.Somewhatincreasetoneutral.Thereissomeevidenceto
suggestthatreproductivesuccessispositivelyinfluencedbyprecipitation,butlong‐term
continuousmonitoringisneededtounderstandwhetherprecipitationconsistentlyexplains
reproductiveoutputandtopredictthepotentialeffectsoffutureclimatechangeonrattlesnake
recruitment.(Spearetal.2011).
ClimateChangeVulnerabilityAssessmentforColoradoBLM323
C2c)Dependenceonaspecificdisturbanceregimelikelytobeimpactedbyclimatechange.
Neutral.TheMidgetfadedrattlesnakeisnotdependentuponspecificdisturbanceregimessuchas
fires,floods,severewinds,pathogenoutbreaks,orsimilarevents.
C2d)Dependenceonsnow‐coveredhabitats.Neutral.TheMidgetfadedrattlesnakeisnot
dependentonhabitatswithice,snow,oronsnowpack.
C3)Restrictiontouncommongeologicalfeaturesorderivatives.Increase.Midgetfaded
rattlesnakesrequirerockoutcropsforhibernacula/denning(ParkerandAnderson2007andSpear
etal.2011).
C4a)Dependenceonotherspeciestogeneratehabitat.Neutral.TheMidgetfadedrattlesnakeis
notdependentonanyotherspeciestocreatesuitablehabitatforitsexistence.
C4b)Dietaryversatility.Neutral.Midgetfadedrattlesnakesmainlypreyonlizards,buteatabroad
rangeofpreyincludingsmallmammalsandbirds(ParkerandAnderson2007).
C4d)Dependenceonotherspeciesforpropaguledispersal.Neutral.TheMidgetfaded
rattlesnakeisaself‐disperser.
C4e)Formspartofaninterspecificinteractionnotcoveredby4a‐d.Neutral.Noother
interspecificinteractionsareimportanttothepersistenceoftheMidgetfadedrattlesnake.
C5a)Measuredgeneticvariation.Somewhatincreasetoneutral.Overall,geneticdiversityislow
tointermediateacrossmidgetfadedrattlesnake(Spearetal.2011).
C5b)Occurrenceofbottlenecksinrecentevolutionaryhistory.Unknown.
C6)Phenologicalresponsetochangingseasonaltemperatureandprecipitationdynamics.
Unknown.
D1)Responsetorecentclimatechange.Unknown.
D2)Modeledfuturechangeinpopulationorrangesize.Decrease.Winterrangeispredictedto
increaseby69%by2080(NAS2014).
D3)Overlapofmodeledfuturerangewithcurrentrange.Unknown.
D4)Protectedareas.Unknown.
Literature Cited
ColoradoNaturalHeritageProgram(CNHP).1998.Midgetfadedrattlesnakeelementglobalrank(EGR)report.Colorado
NaturalHeritageProgram,FortCollins,CO.
Hammerson,G.A.1999.AmphibiansandreptilesinColorado.2nded.UniversityPressofColorado,Boulder,Colorado.364
pp.
324ColoradoNaturalHeritageProgram©2015
Melillo,J.M.,T.C.Richmond,andG.W.Yohe,Eds.,2014:ClimateChangeImpactsintheUnitedStates:TheThirdNational
ClimateAssessment.U.S.GlobalChangeResearchProgram,841pp.doi:10.7930/J0Z31WJ2.
NatureServe.2014.NatureServeExplorer:Anonlineencyclopediaoflife[webapplication].Version7.1.NatureServe,
Arlington,Virginia.Availablehttp://explorer.natureserve.org[2/6/2015].
Parker,J.M.andS.H.Anderson.2007.Ecologyandbehaviorofthemidgetfadedrattlesnake(Crotalusoreganusconcolor)
inWyoming.JournalofHerpetology,41:41‐51.
Reed,R.N.,andM.E.Douglas.2002.EcologyoftheGrandCanyonrattlesnake(Crotalusviridisabyssus)intheLittle
ColoradoRivercanyon,Arizona.SouthwesternNaturalist47:30‐39.
Spear,S.F.,J.M.Parker,C.R.PetersonandC.L.Jenkins.2011.Conservationandmanagementofmidgetfadedrattlesnakes:
statewildlifegrantfinalreport.TheOrianneSociety,Clayton,GA.

ClimateChangeVulnerabilityAssessmentforColoradoBLM325
4 PLANTS
Authors:
JillHandwerk
BernadetteKuhn
DeliaMalone
Recommendedchaptercitation:
Handwerk,J.,B.Kuhn,andD.Malone.2015.Plants.Chapter4InColoradoNaturalHeritageProgram2015.ClimateChange
VulnerabilityAssessmentforColoradoBureauofLandManagement.K.Decker,L.Grunau,J.Handwerk,andJ.Siemers,editors.
ColoradoNaturalHeritageProgram,ColoradoStateUniversity,FortCollins,Colorado.

326ColoradoNaturalHeritageProgram©2015
TableofContents–4Plants
Methods....................................................................................................................................................329
Results.......................................................................................................................................................333
PlantSpeciesCCVASummaries.................................................................................................................336
Aleteslatilobus(Lomatiumlatilobum)......................................................................................................337
Aleteslithophilus(Neoparryalithophila)..................................................................................................340
Amsoniajonesii.........................................................................................................................................344
Aquilegiachrysanthavar.rydbergii..........................................................................................................348
Asclepiasuncialisssp.uncialis..................................................................................................................351
Astragalusanisus.......................................................................................................................................354
Astragalusdebequaeus.............................................................................................................................357
Astragalusequisolensis(Astragalusdesperatusvar.neeseae)................................................................361
Astragalusmicrocymbus...........................................................................................................................364
Astragalusnaturitensis.............................................................................................................................367
Astragalusosterhoutii...............................................................................................................................370
Astragaluspiscator....................................................................................................................................373
Astragalusrafaelensis...............................................................................................................................376
Astragalusripleyi.......................................................................................................................................379
Astragalustortipes....................................................................................................................................383
Bolophytaligulata(Partheniumligulatum)...............................................................................................386
Camissoniaeastwoodiae...........................................................................................................................390
Cleome(Peristome)multicaulis................................................................................................................393
Corispermumnavicula..............................................................................................................................396
Cryptogrammastelleri..............................................................................................................................399
Erigeronkachinensis.................................................................................................................................402
Eriogonumbrandegeei..............................................................................................................................405
Eriogonumclavellatum.............................................................................................................................408
Eriogonumcoloradense............................................................................................................................411
Eriogonumcontortum...............................................................................................................................414
Eriogonumephedroides............................................................................................................................419
Eriogonumpelinophilum..........................................................................................................................424
Eutremapenlandii.....................................................................................................................................427
Gentianellatortuosa.................................................................................................................................430
ClimateChangeVulnerabilityAssessmentforColoradoBLM327
Gilia(Aliciella)stenothyrsa.......................................................................................................................435
Gutierreziaelegans...................................................................................................................................440
Ipomopsispolyantha.................................................................................................................................443
Lomatiumconcinnum...............................................................................................................................446
Lupinuscrassus.........................................................................................................................................449
Mimuluseastwoodiae...............................................................................................................................452
Nuttallia(Mentzelia)chrysantha..............................................................................................................455
Nuttallia(Mentzelia)densa.......................................................................................................................458
Nuttallia(Mentzelia)rhizomata................................................................................................................461
Oenotheraacutissima............................................................................................................................... 465
Oreocarya(Cryptantha)caespitosa..........................................................................................................468
Oreocarya(Cryptantha)osterhoutii.........................................................................................................473
Oreocaryarevealii(Cryptanthagypsophila).............................................................................................476
Oreocarya(Cryptantha)rollinsii................................................................................................................479
Pediomelumaromaticum.........................................................................................................................484
Penstemondebilis.....................................................................................................................................487
Penstemondegeneri.................................................................................................................................490
Penstemongibbensii.................................................................................................................................493
Penstemongrahamii.................................................................................................................................496
Penstemonharringtonii............................................................................................................................499
Penstemonpenlandii................................................................................................................................503
Penstemonscariosusvar.albifluvis..........................................................................................................506
Phaceliaformosula....................................................................................................................................509
Phaceliasubmutica...................................................................................................................................512
Physaria(Lesquerella)congesta................................................................................................................515
Physariaobcordata...................................................................................................................................518
Physaria(Lesquerella)parviflora..............................................................................................................521
Physaria(Lesquerella)pruinosa................................................................................................................ 524
Physariapulvinata.....................................................................................................................................527
Physaria(Lesquerella)vicina.....................................................................................................................530
Sclerocactusglaucus.................................................................................................................................533
Sisyrinchiumpallidum...............................................................................................................................536
Thalictrumheliophilum
.............................................................................................................................539

328ColoradoNaturalHeritageProgram©2015
ListofFiguresandTables
Figure 4.1.Summaryofclimatechangevulnerabilityscoresforplantspecies.EV=ExtremelyVulnerable;
HV=HighlyVulnerable;MV=ModeratelyVulnerable;PS=PresumedStable;IL=IncreaseLikely.......335
Table 4.1.ClimateChangeVulnerabilityScoresforPlantSpecies.EV=ExtremelyVulnerable;HV=Highly
Vulnerable;MV=ModeratelyVulnerable;PS=PresumedStable;IL=IncreaseLikely...........................333

ClimateChangeVulnerabilityAssessmentforColoradoBLM329
METHODS
NatureServe Climate Change Vulnerability Index
Overview
Thisoverviewhasbeensynthesizedandreprinted,withpermission,fromYoungetal.(2011).The
ClimateChangeVulnerabilityIndex(CCVI),developedbyNatureServe,isaMicrosoftExcel‐based
toolthatfacilitatesrapidassessmentofthevulnerabilityofplantandanimalspeciestoclimate
changewithinadefinedgeographicarea.Inaccordancewithwell‐establishedpractices(Schneider
etal.2007,Williamsetal.2008),theCCVIdividesvulnerabilityintotwocomponents:
exposuretoclimatechangewithintheassessmentarea(e.g.,ahighlysensitivespecieswill
notsufferiftheclimatewhereitoccursremainsstable).
sensitivityofthespeciestoclimatechange(e.g.,anadaptablespecieswillnotdeclineeven
inthefaceofsignificantchangesintemperatureand/orprecipitation).
Exposuretoclimatechangeismeasuredbyexaminingthemagnitudeofpredictedtemperatureand
moisturechangeacrossthespecies’distributionwithinthestudyarea.CCVIguidelinessuggest
usingthedownscaleddatafromClimateWizard(http://climatewizard.org)forpredictedchangein
temperature.ProjectionsforchangesinprecipitationareavailableinClimateWizard,but
precipitationestimatesaloneareoftenanunreliableindicatorofmoistureavailabilitybecause
increasingtemperaturespromotehigherratesofevaporationandevapotranspiration.Moisture
availability,ratherthanprecipitationperse,isacriticalresourceforplantsandanimalsand
thereforeformstheotherpartoftheexposuremeasurewithintheCCVI,togetherwith
temperature.Topredictchangesinmoistureavailability,NatureServeandpartnersdevelopedthe
HamonAET:PETmoisturemetricaspartoftheCCVI.Themetricrepresentstheratioofactual
evapotranspiration(i.e.,theamountofwaterlostfromasurfacethroughevaporationand
transpirationbyplants)topotentialevapotranspiration(i.e.,thetotalamountofwaterthatcould
beevaporatedundercurrentenvironmentalconditions,ifunlimitedwaterwasavailable).Negative
valuesrepresentdryingconditions.
Sensitivityisassessedusing20factorsdividedintotwocategories:1)indirectexposuretoclimate
change;and2)speciesspecificfactors(includingdispersalability,temperatureandprecipitation
sensitivity,physicalhabitatspecificity,interspecificinteractions,andgeneticfactors).Foreach
factor,speciesarescoredonaslidingscalefromgreatlyincreasing,tohavingnoeffecton,to
decreasingvulnerability.TheCCVIaccommodatesmorethanoneanswerperfactorinorderto
addresspoordataorahighlevelofuncertaintyforthatfactor.Thescoringsystemintegratesall
exposureandsensitivitymeasuresintoanoverallvulnerabilityscorethatindicatesrelative
vulnerabilitycomparedtootherspeciesandtherelativeimportanceofthefactorscontributingto
vulnerability.
330ColoradoNaturalHeritageProgram©2015
TheIndextreatsexposuretoclimatechangeasamodifierofsensitivity.Iftheclimateinagiven
assessmentareawillnotchangemuch,noneofthesensitivityfactorswillweighheavily,anda
speciesislikelytoscoreattheNotVulnerableendoftherange.Alargechangeintemperatureor
moistureavailabilitywillamplifytheeffectofanyrelatedsensitivity,andwillcontributetoascore
reflectinghighervulnerabilitytoclimatechange.Inmostcases,changesintemperatureand
moistureavailabilitywillcombinetomodifysensitivityfactors.However,forfactorssuchas
sensitivitytotemperaturechange(factor2a)orprecipitation/moistureregime(2b),onlythe
specifiedclimatedriverwillhaveamodifyingeffect.
Thesixpossiblescoresare:
ExtremelyVulnerable:Abundanceand/orrangeextentwithingeographicalareaassessed
extremelylikelytosubstantiallydecreaseordisappearby2050.
HighlyVulnerable:Abundanceand/orrangeextentwithingeographicalareaassessedlikelyto
decreasesignificantlyby2050.
ModeratelyVulnerable:Abundanceand/orrangeextentwithingeographicalareaassessedlikely
todecreaseby2050.
NotVulnerable/PresumedStable:Availableevidencedoesnotsuggestthatabundanceand/or
rangeextentwithinthegeographicalareaassessedwillchange(increase/decrease)substantially
by2050.Actualrangeboundariesmaychange.
NotVulnerable/IncreaseLikely:Availableevidencesuggeststhatabundanceand/orrangeextent
withingeographicalareaassessedislikelytoincreaseby2050.
InsufficientEvidence:Availableinformationaboutaspecies'vulnerabilityisinadequateto
calculateanIndexscore.
Scoring Factors in the CCVI
ThefactorsusedtogeneratetheCCVIscorearelistedinthefollowingsection.Detaileddefinitions
ofscoringcategoriesarelistedinAppendixB.
A.ExposuretoLocalClimateChange
1. Temperature
2. Moisture
B.IndirectExposuretoClimateChange
1. Exposuretosealevelrise.(NotapplicabletoColorado)
2. Distributionrelativetonaturalandanthropogenicbarriers.
ClimateChangeVulnerabilityAssessmentforColoradoBLM331
3. Predictedimpactoflandusechangesresultingfromhumanresponsestoclimate
change.
C.Sensitivity
1. Dispersalandmovements.
2. Predictedsensitivitytotemperatureandmoisturechanges.
a.Predictedsensitivitytochangesintemperature.
b.Predictedsensitivitytochangesinprecipitation,hydrology,ormoisture
regime.
c.Dependenceonaspecificdisturbanceregimelikelytobeimpactedby
climatechange.
d.Dependenceonice,ice‐edge,orsnow‐coverhabitats.
3. Restrictiontouncommongeologicalfeaturesorderivatives.
4. Relianceoninterspecificinteractions.
a.Dependenceonotherspeciestogeneratehabitat.
b.Dietaryversatility(animalsonly).
c.Pollinatorversatility(plantsonly).
d.Dependenceonotherspeciesforpropaguledispersal.
e.FormspartofaninterspecificinteractionnotcoveredbyC4a‐d.
5. Geneticfactors.
a.Measuredgeneticvariation.
b.Occurrenceofbottlenecksinrecentevolutionaryhistory.
6. Phenologicalresponsetochangingseasonaltemperatureandprecipitation
dynamics.
D.DocumentedorModeledResponsetoClimateChange
1. Documentedresponsetorecentclimatechange.
2. Modeledfuturechangeinrangeorpopulationsize.
3. Overlapofmodeledfuturerangewithcurrentrange.
4. Occurrenceofprotectedareasinmodeledfuturedistribution.
Factorsnotconsidered—TheIndexdevelopmentteamdidnotincludefactorsthatarealready
consideredinconservationstatusassessments.Thesefactorsincludepopulationsize,rangesize,
anddemographicfactors.ThegoalisfortheNatureServeClimateChangeVulnerabilityIndexto
complementNatureServeConservationStatusRanksandnottopartiallyduplicatefactors.Ideally,
Indexvaluesandstatusranksshouldbeusedinconcerttodetermineconservationpriorities.
Application of Climate Data
Scoringfactorsrelatedtohistoricandpredictedfutureclimate(temperature,precipitation,and
moistureavailability,FactorsA1,A2,C2ai,andC2biintheCCVI)werecalculatedinGISusingthe
methodsdescribedbelow.Refertothespeciesprofilesinthefollowingsectionofthisreportfor
detailsonscoringrationaleandreferencesforallotherfactors.
332ColoradoNaturalHeritageProgram©2015
Exposuretopredictedtemperatureincreasewascalculatedusingspeciesdistributiondataandan
ensembleaverageof16CMIP3climatepredictionmodels(seeAppendixA)averagedoverthe
summerseason(June–August)usingthehigh(A2)CO2emissionsscenario.Thehighemissions
scenariowasusedbecauseitismostsimilartocurrentemissions.DatawasobtainedfromClimate
Wizard,andtheanalysisperiodwastotheyear2050(whichisactuallyanaverageofprojections
foryears2040–2069).Thesummerseason–growingseasonforplants,breedingseasonfor
animals–wasusedbecauseitwasconsideredthemostcriticaltimeperiodformostspecies.
Exposuretoprojecteddrying(integrationofprojectedtemperatureandprecipitationchange,i.e.,
theHamonAET:PETmoisturemetric)wascalculatedusingthedatasetcreatedbyNatureServeas
partoftheCCVI.NotethatNatureServebasedtheirmoisturemetriccalculationsonthesame
ClimateWizarddatasetasabove,exceptthattheyusedtheA1Bcarbondioxideemissionsscenario.
BecausethemodelingmethodsusedbyNatureServewerenotavailable,wewereunableto
recalculateusingtheA2scenario.Thus,weusedthedataasprovided,whichweconsidereda
reasonablealternativesincetheA1BandA2scenariospredictsimilarchangesthroughthemid‐21st
Century,theperiodusedinthisanalysis.Wecalculatedthepercentofeachspecies’
range/distributionthatfallswithineachratingcategory.Allcalculationsusedthe“summer”(June–
August)datasubset.
Thehistoricalthermalnichefactormeasureslarge‐scaletemperaturevariationthataspecieshas
experiencedinrecenthistoricaltimes(i.e.,thepast50years),asapproximatedbymeanseasonal
temperaturevariation(differencebetweenhighestmeanmonthlymaximumtemperatureand
lowestmeanmonthlyminimumtemperature).Itisaproxyforspecies'temperaturetoleranceata
broadscale.ThisfactorwascalculatedinGISbyassessingtherelationshipbetweenspecies’
distributionsandhistoricaltemperaturevariationdatadownloadedfromNatureServe.Historical
temperaturevariationwasmeasuredasthemeanJulyhighminusthemeanJanuarylow,using
PRISMdatafrom1951‐2006,expressedasasingleaveragedvaluefortheentirespeciesrange.
Thehistoricalhydrologicalnichefactormeasureslarge‐scaleprecipitationvariationthataspecies
hasexperiencedinrecenthistoricaltimes(i.e.,thepast50years),asapproximatedbymeanannual
precipitationvariationacrossoccupiedcellswithintheassessmentarea.Ratingsforthisfactor
werecalculatedinGISbyoverlayingthespecies’distributionsonmeanannualprecipitationdata
(PRISM4kmannualaverageprecipitation,ininches,1951‐2006)downloadedfromClimateWizard,
andsubtractingthelowestpixelvaluefromthehighestvalue.
Representing Species’ Distributions
Forplantspecies,weusedelementoccurrencesfromCNHP’sBIOTICSdatabasetogenerate
distributionmapsandperformtheGIScalculationsreferencedabove.
Theplantspeciesincludedinthisclimatechangevulnerabilityassessmentincludeallthefederally
listed(threatened,endangeredandcandidate)speciesknowntooccuronBLMlands.Alsoincluded
arealltheplantspeciesfromtheBLMSensitiveSpecieslist,withtheexceptionof13speciesfor
whichtherewasnotsufficientinformationavailabletoevaluatetheeffectsofclimatechange.The
omittedspecieswere:Arabiscrandallii(Boecheracrandallii),Astragalusmusiniensis,Astragalus
ClimateChangeVulnerabilityAssessmentforColoradoBLM333
sesquiflorus,Cymopterusduchesnensis,Eriogonumacaule,Eriogonumtumulosum,Eriogonum
viridulum,Fraserapaniculata,Lygodesmiadoloresensis,Packerapauciflora,Sphaeromeriacapitata,
Townsendiastrigosa,Trichophorumpumilum(Scirpusrollandii).
RESULTS
CCVIresultsaresummarizedinTable4.1,andpresentedinfullinAppendixC.Plantspeciesresults
aresortedalphabeticallybyscientificname.Therationaleforscoringandliteraturecitationsare
includedinthefollowingspeciesprofiles.
Table 4.10.ClimateChangeVulnerabilityScoresforPlantSpecies.EV=ExtremelyVulnerable;HV=Highly
Vulnerable;MV=ModeratelyVulnerable;PS=PresumedStable;IL=IncreaseLikely.
Species English name Score
Aleteslatilobus(Lomatiumlatilobum)CanyonlandsaletesEV
Aleteslithophilus(Neoparryalithophila)Rock‐lovingneoparryaEV
AmsoniajonesiiJones'bluestarMV
Aquilegiachrysanthavar.rydbergiiGoldencolumbineEV
Asclepiasuncialisssp.uncialisDwarfmilkweedEV
AstragalusanisusGunnisonmilkvetchEV
AstragalusdebequaeusDeBequemilkvetchEV
AstragalusequisolensisHorseshoemilkvetchEV
AstragalusmicrocymbusSkiffmilkvetchEV
AstragalusnaturitensisNaturitamilkvetchEV
AstragalusosterhoutiiKremmlingmilkvetchEV
AstragaluspiscatorFisherTowersmilkvetchEV
AstragalusrafaelensisSanRafaelmilkvetchEV
AstragalusripleyiRipleymilkvetchEV
AstragalustortipesSleepingUtemilkvetchEV
Bolophytaligulata(Partheniumligulatum)LigulatefeverfewEV
CamissoniaeastwoodiaeEastwoodeveningprimroseHV
CleomemulticaulisSlenderspiderflowerEV
CorispermumnaviculaBoat‐shapedbugseedEV
CryptogrammastelleriSlenderrock‐brakeEV
ErigeronkachinensisKachinadaisyEV
EriogonumbrandegeeiBrandegeewildbuckwheatEV
EriogonumclavellatumCombWashbuckwheatEV
EriogonumcoloradenseColoradowildbuckwheatEV
EriogonumcontortumTwistedBuckwheatEV
EriogonumpelinophilumClay‐lovingwildbuckwheatEV
334ColoradoNaturalHeritageProgram©2015
Species English name Score
EriogonumephedroidesEphedrabuckwheatEV
EutremapenlandiiPenlandalpinefenmustardEV
GentianellatortuosaUtahgentianEV
Gilia(Aliciella)stenothyrsaNarrow‐stemGiliaEV
GutierreziaelegansLoneMesasnakeweedEV
IpomopsispolyanthaPagosaskyrocketEV
LomatiumconcinnumColoradodesert‐parsleyEV
LupinuscrassusPaysonlupineEV
MimuluseastwoodiaeEastwood'smonkeyflowerEV
Nuttallia(Mentzelia)chrysanthaGoldenblazingstarEV
Nuttallia(Mentzelia)densaArkansasCanyonstickleafEV
Nuttallia(Mentzelia)rhizomataRoanCliffsBlazingstarEV
OenotheraacutissimaNarrow‐leafeveningprimroseHV
Oreocarya(Cryptantha)caespitosaTuftedCryptanthEV
Oreocarya(Cryptantha)rollinsiiRollins'Cats‐eyeEV
Oreocaryaosterhoutii(Cryptanthaosterhoutii)Osterhout'scat's‐eyeEV
Oreocaryarevealii(Cryptanthagypsophila)GypsumValleycat's‐eyeEV
PediomelumaromaticumParadoxbreadrootEV
PenstemondebilisParachutepenstemonEV
PenstemondegeneriDegenerbeardtongueEV
PenstemongibbensiiGibben'sbeardtongueEV
PenstemongrahamiiGrahambeardtongueEV
PenstemonharringtoniiHarrington'sbeardtongueEV
PenstemonpenlandiiPenlandpenstemonEV
Penstemonscariosusvar.albifluvisWhiteRiverpenstemonEV
PhaceliaformosulaNorthParkphaceliaEV
PhaceliasubmuticaDeBequephaceliaEV
Physaria(Lesquerella)congestaDudleyBluffsbladderpodEV
Physaria(Lesquerella)parvifloraPiceancebladderpodEV
Physaria(Lesquerella)pruinosaPagosabladderpodEV
Physaria(Lesquerella)vicinaGood‐neighborbladderpodEV
PhysariaobcordataPiceancetwinpodEV
PhysariapulvinataCushionbladderpodEV
SclerocactusglaucusColoradohooklesscactusEV
SisyrinchiumpallidumPaleblue‐eyedgrassEV
ThalictrumheliophilumSun‐lovingmeadowrueEV
ClimateChangeVulnerabilityAssessmentforColoradoBLM335
Nearlyallofthe62plantspeciesanalyzedscoredasextremelyvulnerabletopredictedclimate
changeinColorado.Onlythreespecies(Amsoniajonesii,CamissoniaeastwoodiaeandOenothera
acutissima)werehighlytomoderatelyvulnerable.Noneoftheplantspeciesscoredaspresumed
stableorlikelytoincreaseundertheclimatechangescenariousedinthisanalysis.(Table4.1).
Factorsthatweremostlikelytocontributetothevulnerabilityofplantsinclude:naturalbarriersto
movementandpoordispersalability,physiologicalhydrologicalniche,restrictiontouncommon
geologicfeaturesorsubstrates,andpollinatorspecificity.Ofthe62plantspeciesevaluatedfor
Coloradotheconfidenceratingswereveryhighforallspecies.
Despitethedevelopmentofnumerousclimatechangemodels,thereremainssomeuncertainty
aboutwhatclimaticchangeswillactuallyoccurandhowspeciesfitnessandpopulationstability
willbeaffected.Whenevaluatedataregional(i.e.,smallerthanstatewide)scale,somespecies
scoredaslessvulnerabletoclimatechange.Forexample,intheSanJuanregionofColorado,
Amsoniajonesiiispresumedstablewheretherearefewnaturaloranthropogenicbarriersto
movementandithasbeenexposedtogreaterhistoricaltemperaturevariation,whereasitscoresas
moderatelyvulnerableonastatewidescalewherethepresenceofnaturalandanthropogenic
barriersincreasesandthereislessexposuretohistorictemperatureextremes.Mimulus
eastwoodiaescoredashighlyvulnerableintheSanJuanregionbutisconsideredextremely
vulnerableonastatewidescaleforthesamereasons,increasedbarrierstomovementandless
exposuretohistorictemperaturevariation.ThesamewastrueforPediomelumaromaticumwhich
ismoderatelyvulnerableintheSanJuan’sandextremelyvulnerablestatewide.Thus,itisimportant
toconsiderthespeciesrangeinrelationtotheassessmentareawhendevelopingadaption
strategies,andtoconsiderhowsuchfactors,suchasprecipitationandtemperatureaveragescan
affectthescoreswhenspeciesareevaluatedatdifferentscales.
Figure 4.1.Summaryofclimatechangevulnerabilityscoresforplantspecies.EV=ExtremelyVulnerable;HV=
HighlyVulnerable;MV=ModeratelyVulnerable;PS=PresumedStable;IL=IncreaseLikely.
336ColoradoNaturalHeritageProgram©2015
PLANT SPECIES CCVI SUMMARIES
ClimateChangeVulnerabilityAssessmentforColoradoBLM337
Aleteslatilobus(Lomatiumlatilobum)
Canyonlandsaletes
G1G2/S1
Family:Apiaceae
Photo:GinaGlenne
Climate Vulnerability Rank: Extremely Vulnerable
ThisColoradostate‐widerankisbasedonthefollowingfactors:1)1)Aleteslatilobushabitatis
surroundedbyanthropogenicandnaturalbarriersthatmayinhibitrangeshift2)potentialincrease
inenergydevelopmentinA.latilobushabitat;3)A.latilobushasexperiencedasmallrangeinmean
annualprecipitationoverthelast50years;4)seeddispersaldistancesareprobablyfairlylimited;
5)potentialdecreaseinsoilmoistureavailabilityunderprojectedwarmertemperatures;6)
restrictiontosandstoneEntradaandNavajoFormations.
Distribution:ColoradoPlateau,NavajoBasin;GrandandSanJuanCounties,Utah,andMesa
County,Colorado.Habitat:OnEntradaSandstoneandNavajoSandstone,betweenfinsandinslot
canyons,insandysoilandincrevices.Surroundingplantcommunitiesaredesertshrub,pinyon‐
juniper,orponderosapine‐mountainbrush.Foundincanyonlandsinpinyon‐juniperanddesert
shrubcommunities;onsandstoneledgesandinsandysoilsderivedfromtheEntradaFormationor
thecontactpointoftheWingateandChinleFormations(Spackmanetal.1997,Ackerfield2012,
WeberandWittmann2012).Elevation:4541‐5807feet.
EcologicalSystem:CliffandCanyon,DesertShrub
CCVI Scoring
B1)Exposuretosealevelrise.Neutral.
338ColoradoNaturalHeritageProgram©2015
B2a)Distributionrelativetonaturalbarriers.Increase.Rangeshiftinresponsetoclimate
changeisinhibitedbyunsuitablegeologyandtheColoradoRiverValley(tothenorth)thatdonot
containsuitablehabitatforthisspecies(USGS2004).
B2b)Distributionrelativetoanthropogenicbarriers.Increase.Extensivehabitatalterationdue
tooilandgasextractioninandaroundhabitatoccupiedbythisspecies(FracFocusWells2013)
inhibitsrangeshift.Additionally,muchofthelandscapesurroundingoccurrencesofA.latilobushas
beenalteredbylivestockgrazing(CNHP2014).
B3)Impactoflandusechangesresultingfromhumanresponsestoclimatechange.Increase.
Desertshrublandshavehighpotentialfornaturalgasextraction,andsolarandwindenergy
development(Grunauetal.2011;NRDC2011).
C1)Dispersalandmovements.Increase.Seedslikelyfallclosetoparentplant.
C2ai)Predictedsensitivitytotemperature:historicthermalniche.Neutral.Consideringthe
meanseasonaltemperaturevariationforoccupiedcells,thespecieshasexperiencedaverage(57.1‐
77°F/31.8‐43.0°C)temperaturevariationinthepast50years.
C2aii)Predictedsensitivitytotemperature:physiologicalthermalniche.Increase.Cliffand
canyonspecieswererated‘Increase’basedontheassumptionthatthesehabitatsarelikelytobe
alteredasColoradobecomeswarmer.
C2bi) Predictedsensitivitytochangesinprecipitation,hydrology,ormoistureregime:
historicalhydrologicalniche.GreatlyIncrease.Consideringtherangeofmeanannual
precipitationacrossoccupiedcells,thespecieshasexperiencedverysmall(<4inches/100mm)
precipitationvariationinthepast50years.
C2bii)Predictedsensitivitytochangesinprecipitation,hydrology,ormoistureregime:
physiologicalhydrologicalniche.Increase.Climatemodelsprojecthottertemperaturesfor
Colorado,withtrendstowardmoreseveresoil‐moisturedroughtconditionsinColorado(Lukaset
al.2014).Warmertemperatureswillresultinhigherevapotranspirationratesforplants.A.
latilobusoccursinasemi‐aridclimatewithanaverageof11.33inchesofprecipitationperyear
(WesternRegionalClimateCenter2015).Althoughtolerancelimitsforlackofmoistureare
unknownforthisspecies,ahotterclimatecombinedwithhigherevapotranspirationmayresultin
stressfulconditionsforA.latilobus.
C2c)Dependenceonaspecificdisturbanceregimelikelytobeimpactedbyclimatechange.
Neutral.
C2d)Dependenceonice,ice‐edge,orsnowcoverhabitats.Neutral.Thisspeciesisnotrestricted
toordependentoniceorsnowcoverhabitats.
C3)Restrictiontouncommongeologicalfeaturesorderivatives.SomewhatIncrease.
RestrictedtosandstonesoftheEntradaandNavajoFormations(CNHP2014).
ClimateChangeVulnerabilityAssessmentforColoradoBLM339
C4a)Dependenceonotherspeciestogeneratehabitat.Neutral.Thereisnoevidencethatthis
speciesisdependentonotherspeciestogeneratehabitat.
C4c)PollinatorVersatility.Unknown.
C4d)Dependenceonotherspeciesforpropaguledispersal.Unknown.
C4e)FormspartofaninterspecificinteractionnotcoveredbyC4a‐d.Unknown.
C5a)Measuredgeneticvariation.Unknown.
C5b)Occurrenceofbottlenecksinrecentevolutionaryhistory.Unknown.
C6)Phenologicalresponsetochangingseasonaltemperatureandprecipitationdynamics.
Unknown.
Literature Cited
Ackerfield,J.2012.TheFloraofColorado.ColoradoStateUniversityHerbarium.433pp.
ColoradoNaturalHeritageProgram.1997+.ColoradoRarePlantGuide.www.cnhp.colostate.edu.Latestupdate:June30,
2014.
ColoradoNaturalHeritageProgram(CNHP).2014.BiodiversityTrackingandConservationSystem(BIOTICS).Colorado
NaturalHeritageProgram,ColoradoStateUniversity,FortCollins.
FracFocusWells.2013.MapProvidedbyFracTrackerAllianceonFracTracker.org.Availableat:
http://www.fractracker.org/map/national/
Grunau,L.,J.Handwerk,andS.Spackman‐Panjabi,eds.2011.ColoradoWildlifeActionPlan:proposedrareplant
addendum.ColoradoNaturalHeritageProgram,ColoradoStateUniversity,FortCollins,CO.
Lukas,J.,J.Barsugli,N.Doesken,I.Rangwala,andK.Wolter2014.ClimateChangeinColorado,ASynthesistoSupport
WaterResourcesManagementandAdaptation,SecondEdition.Availableat:
http://wwa.colorado.edu/climate/co2014report/.Accessed:2014.
NaturalResourcesDefenseCouncil[NRDC].2011.RenewableenergyforAmerica:harvestingthebenefitsofhomegrown,
renewableenergy.Online.Available:http://www.nrdc.org/energy/renewables/energymap.asp(accessed2014).
Spackman,S.,B.Jennings,J.Coles,C.Dawson,M.Minton,A.Kratz,andC.Spurrier.1997.Coloradorareplantfieldguide.
PreparedforBureauofLandManagement,U.S.ForestServiceandU.S.FishandWildlifeServicebyColoradoNatural
HeritageProgram.
USGSNationalGapAnalysisProgram.2004.ProvisionalDigitalLandCoverMapfortheSouthwesternUnitedStates.
Version1.0.RS/GISLaboratory,CollegeofNaturalResources,UtahStateUniversity.
Weber,W.A.andR.C.Wittmann.2012.ColoradoFlora,WesternSlope,AFieldGuidetotheVascularPlants,FourthEdition.
Boulder,Colorado.532pp.
WesternRegionalClimateCenter.2015.AverageannualprecipitationforGrandJunction,Colorado.
http://www.wrcc.dri.edu/cgi‐bin/cliMAIN.pl?co3488.AccessedFeb24,2015.PeriodofRecord:1900to2015.

340ColoradoNaturalHeritageProgram©2015
Aleteslithophilus(Neoparryalithophila)
Rock‐lovingneoparrya
G3/S3
Family:Apiaceae
Photo:JimMcCain
Climate Vulnerability Rank: Highly Vulnerable
ThisColoradostate‐widerankisbasedon:predicteddecreasesinprecipitation;thediscontinuityof
suitablehabitatthatisolatespopulationsandcreatesnaturalbarriersandhabitatalterationthat
resultsfromlivestockgrazingwhichactsasananthropogenicbarriers;possiblewindpower
developmentthatmayoccurincurrentandpotentialfuturerange;limitedsuccessfulseed
dispersal;andalterationofthenaturalfiredisturbanceregime.Suitablehabitatislikelytobe
reducedasthisspecies’rangebecomesdrier.Climatemodelsprojectannualnetdryingacrossthe
rangeofthisspecies(NatureServe2012)withresultingtrendstowardmoreseveresoil‐moisture
droughtconditionsinColorado(Lukasetal.2014)
Distribution:AleteslithophilusisendemictothesouthernRockyMountainswherethisspeciesis
knownfromsevencountiesinsouth‐centralColorado:Chaffee,Conejos,Fremont,Huerfano,
Mineral,RioGrande,andSaguache;andhasalsobeenreportedfromonesiteinnorth‐centralRio
BravoCountyinNewMexico(Anderson2004,SEINet2014).Mostoccurrencesareknownfromthe
westernrimoftheSanLuisValley,butimportantoutlyingoccurrencesarealsofoundinthe
ArkansasValleyintheSalidaareaandatFarisitaDikeinHuerfanoCounty(Anderson2004).
EcologicalSystem/Habitat:AleteslithophilusisfoundintheSouthernRockyMountainSteppe‐
OpenWoodland‐ConiferousForest‐AlpineMeadowProvince(Anderson2004).InthisecosystemN.
lithophilatypicallyoccupiesvolcanicsubstrates,inthecracksorshelvesofmoderatetosteeprock
outcrops,oroutcropsofvolcanicsoils,usuallywithminimaltalusbutisalsoknowntooccuron
sedimentaryrockderivedfromextrusivevolcanics.Habitatsurroundingtherockoutcropsis
typicallygrasslandsorpinon‐juniperwoodlandswithassociatedtaxaoftenincludingFestuca,
Artemisia,Muhlenbergia,Hymenoxys,andRibes(NatureServe2014).Elevation:Reportsdocument
ClimateChangeVulnerabilityAssessmentforColoradoBLM341
thatAleteslithophilusrangesfrom6,700to10,000feet,butismostcommonlyfoundbetween7,280
to9,800feetinelevation(Anderson2004).
CCVI Scoring
B1)Exposuretosealevelrise.Neutral.
B2a)Distributionrelativetonaturalbarriers.Increase.OccurrencesofAleteslithophilusare
naturallyisolatedbythediscontinuityofsuitablehabitat(Anderson2004).Thisspeciesoccupies
rockoutcrops,dikesandcliffsthataredistributedonthelandscapeasislandssurroundedbyasea
ofgrasslandandwoodlandhabitatswheretheinterveningenvironmentisapparentlyunsuitable
fortheestablishmentofA.lithophilusandactsasbarrierstorangeshift.
B2b)Distributionrelativetoanthropogenicbarriers.Somewhatincrease.Habitatalterationas
aconsequenceoflivestockgrazingbothindirectlyanddirectlyimpairsrangeshiftdrivenbyclimate
change.Aleteslithophilusishighlyvulnerabletohabitatalterationasindicatedbya“coefficientof
conservatism”value(Cvalue)of“9”(Rocchio2007).ThemajorityofA.lithophilusoccurrencesare
eitheronoradjacenttolandthatismanagedforlivestockgrazing(BLM2014,CNHP2014)andthe
majorityofthosegrazingallotmentsarecategorizedas“improve”(BLM2014).
B3)Impactoflandusechangesresultingfromhumanresponsestoclimatechange.
Somewhatincrease.NaturalhistoryrequirementsofAleteslithophilusareincompatiblewiththe
landusechangesthatmaypossiblyoccurinitscurrentandfuturerangeasaresultofwindenergy
development.Potentialforwindpowerdevelopmentishighthroughoutthewesternperimeterof
theSanLuisvalley(NRDC2011)wherethemajorityofthedocumentedoccurrencesofN.lithophila
arelocated(CNHP2014).
C1)Dispersalandmovements.Somewhatincrease.Successfulseeddispersalislimitedby
unsuitablehabitat.AlthoughAleteslithophilusseedsmaybedispersedbyavarietyofmechanisms,
includingwindandanimals,withpotentialmaximumdispersaldistancesofupto15and1,500
metersrespectively(JongejansandTelenius2001,VittozandEngler2007),theprobabilityof
dispersaldecreasesrapidlywithincreasingdistancefromthesource(Barbouretal.1987).Flat
areassurroundingtherockoutcropsinhabitedbyN.lithophilapresentunsuitablehabitatthat
undoubtedlyactassinkswhenseedsareblownorwashedontotheseareas(Anderson2004).
C2ai)Predictedsensitivitytotemperature:historicthermalniche.Neutral. Consideringthe
meanseasonaltemperaturevariationforoccupiedcells,thespecieshasexperiencedaverage
temperaturevariation(57.1‐77oF)inthepast50years.
C2aii)Predictedsensitivitytotemperature:physiologicalthermalniche.Neutral.Aletes
lithophilusisnotrestrictedtocoolorcoldenvironments.Additionally,habitatpreferences
(Anderson2004)suggestthatA.lithophilusistolerantofwarmertemperatures.
C2bi) Predictedsensitivitytochangesinprecipitation,hydrology,ormoistureregime:
historicalhydrologicalniche.Neutral.Consideringtherangeofmeanannualprecipitationacross
342ColoradoNaturalHeritageProgram©2015
occupiedcells,thespecieshasexperiencedaverageprecipitationvariation(36.5inches)inthepast
50years.
C2bii)Predictedsensitivitytochangesinprecipitation,hydrology,ormoistureregime:
physiologicalhydrologicalniche.Somewhatincrease.Aleteslithophilusissomewhatdependent
onaseasonalhydrologicregimethatisvulnerabletoalterationwithclimatechangeandassociated
predictedincreasedseverityandfrequencyofdrought(USGCRP2009).AlthoughA.lithophilus
occupiesxericsites,populationmaintenanceviarecruitmentisdependentonseedlingsuccess
whichappearstobedependentonperiodsofoneorseveralwetyearsduringwhichplantscan
becomeestablished(Anderson2004).
C2c)Dependenceonaspecificdisturbanceregimelikelytobeimpactedbyclimatechange.
Increase.WhileseveredroughtsarealreadypartoftheSouthwestclimate,human‐inducedclimate
changewilllikelyresultinmorefrequentandmoreseveredroughtswithassociatedincreasesin
wildfires(USGCRP2009).Additionally,thepresenceofcheatgrass(Bromustectorum)inmany
occurrencesmayfurtherexacerbateclimatechange‐inducedalterationtonaturalfireregimes.
Increasedfirefrequencywillfavorfire‐dependentorfire‐tolerantspecies,whichthisspeciesisnot
(Anderson2004),leadingtowardchangesinspeciescomposition(Noss2001).
C2d)Dependenceonice,ice‐edge,orsnowcoverhabitats.Neutral.Thisspeciesisnotrestricted
toordependentoniceorsnowcoverhabitats.
C3)Restrictiontouncommongeologicalfeaturesorderivatives.Somewhatincrease.Aletes
lithophilusisprimarilyrestrictedtoTertiaryvolcanicsubstrateswiththespeciesprimarily
distributedalongtheeasternmarginoftheSanJuanVolcanicArea(Anderson2004).Tertiary
volcanicsubstratesarewidelydistributedinsouthcentralandsouthwesternColoradowith
Tertiaryashflowtuffandpre‐ashflowvolcanicsunderlyingmuchoftheeasternSanJuan
Mountains(Tweto1979,ChronicandWilliams2002).
C4a)Dependenceonotherspeciestogeneratehabitat.Neutral.Aleteslithophilusisnotknown
tobedependentonotherspeciestogeneratehabitat.
C4c)PollinatorVersatility.Neutral.SpeciesinthefamilyApiaceaehaveahighdegreeoffloral
uniformitywithverylittlefloralspecializationandthusutilizeabroadsuiteofpollinatorsfor
pollenvectors(Anderson2004).
C4d)Dependenceonotherspeciesforpropaguledispersal.Neutral.Aleteslithophilusisnot
knowntobedependentonotherspeciesfordispersal.
C4e)FormspartofaninterspecificinteractionnotcoveredbyC4a‐d.Unknown.
C5a)Measuredgeneticvariation.Unknown.
C5b)Occurrenceofbottlenecksinrecentevolutionaryhistory.Unknown.
C6)Phenologicalresponsetochangingseasonaltemperatureandprecipitationdynamics.
Unknown.
ClimateChangeVulnerabilityAssessmentforColoradoBLM343
Literature Cited
Anderson,D.G.2004.NeoparryalithophilaMathias(Bill’sneoparrya):atechnicalconservationassessment.[Online].USDA
ForestService,RockyMountainRegion.Available:
http://www.fs.fed.us/r2/projects/scp/assessments/neoparryalithophila.pdf
Barbour,M.G.,J.H.Burk,andW.D.Pitts.1987.TerrestrialPlantEcology.Benjamin/CummingsPublishingCompany,Inc.,
MenloPark,CA.
Chronic,H.andF.Williams.2002.RoadsideGeologyofColorado,2nded.MountainPressPublishingCO.,Missoula,
Montana.
ColoradoNaturalHeritageProgram(CNHP).2014.BiodiversityTrackingandConservationSystem(BIOTICS).Colorado
NaturalHeritageProgram,ColoradoStateUniversity,FortCollins.
Jongejans,E.andA.Telenius.2001.Fieldexperimentsonseeddispersalbywindintenumbelliferousspecies(Apiaceae).
PlantEcology152:67–78.
Lukas,J.,J.Barsugli,N.Doesken,I.Rangwala,andK.Wolter2014.ClimateChangeinColorado,ASynthesistoSupport
WaterResourcesManagementandAdaptation,SecondEdition.Availableat:
http://wwa.colorado.edu/climate/co2014report/.Accessed:2014.
NatureServe2012.ClimateChangeVulnerabilityAssessmentTool,version2.1.Availableonlineat
https://connect.natureserve.org/science/climate‐change/ccvi.
NatureServe.2014.NatureServeExplorer:Anonlineencyclopediaoflife[webapplication].Version7.1.NatureServe,
Arlington,Virginia.Availablehttp://explorer.natureserve.org.(Accessed:November14,2014)
Noss,R.(2001).BeyondKyoto:Forestmanagementinatimeofrapidclimatechange.ConservationBiology15(3):578‐
590.
NRDCRenewableEnergyMapNaturalResourcesDefenseCounsel.2011.RenewableenergyforAmerica:harvestingthe
benefitsofhomegrown,renewableenergy.Online.Available:http://www.nrdc.org/energy/renewables/energymap.asp
(accessed2014).
Rocchio,J.2007.FloristicQualityAssessmentIndicesforColoradoPlantCommunities.ColoradoNaturalHeritage
Program,ColoradoStateUniversity,FortCollins,CO.
SouthwestEnvironmentalInformationNetwork(SEINet).2014.Cryptanthacaespitosa.Availableat:
http://swbiodiversity.org/.Accessed2014.
Tweto,O.1979.GeologicMapofColorado.CompiledbytheU.S.GeologicalSurveywithtechnicalassistancebythe
ColoradoGeologicalSurvey.
U.S.DepartmentoftheInterior,BureauofLandManagement(BLM).2014.Geocommunicator.Availableat:
http://www.geocommunicator.gov/GeoComm/.Accessed:2014.
VittozP.andEnglerR.2007.Seeddispersaldistances:atypologybasedondispersalmodesandplanttraits.Bot.Helv.
117:109–124.

344ColoradoNaturalHeritageProgram©2015
Amsoniajonesii
Jones’bluestar
G4/S2
Family:Apocynaceae
Photo:JoeLeahy
Climate Vulnerability Rank: Moderately Vulnerable
ThisColoradostatewiderankisbasedon:predictedincreasedtemperatureanddecreased
precipitationduringperiodoffloweringandfruiting;thepresenceofhighescarpmentsthatactas
naturalbarriersaswellashabitatalterationthatresultsfromenergyextraction,agricultural
developmentandlivestockgrazingthatactasanthropogenicbarrierstorangeshift;possiblewind
powerdevelopmentwhichmayimpactpotentialfuturerange;alterationtothenaturalfire
disturbanceregime;pollinatorlimitation;predicteddecreaseinmodeledfuturerangewithlittle
habitatincludedinprotectedareas.Suitablehabitatislikelytobelosttothisspeciesand
reproductivesuccessdiminished.Climatemodelsprojectannualnetdryingthroughouttherangeof
thisspecies(NatureServe2012)whichmayimpactrecruitmentandpopulationsurvivability.
Distribution:A.jonesiiisknownfromNEArizona,Utah,NWNewMexico,andSWColoradointhe
UnitedStates(NatureServe2014).InColorado,itisknownfromMesaandMontezumacounties
(USDANRCS2013,CNHP2014).Habitat:Dry,openareaswithclay,sandy,orgravellysoils,in
desert‐steppe,rockydrainagesanddraws(CNHP2014).Elevation:4400‐5800feet.
EcologicalSystem:DesertShrublands,Pinyon‐JuniperWoodlands
CCVI Scoring
B1)Exposuretosealevelrise.Neutral.
B2a)Distributionrelativetonaturalbarriers.SomewhatIncrease.Withachangingclimate
Amsoniajonesiiispredictedtomovenorthward,trackingclimatemoresuitabletoitsevolved
environmentaltolerancesandecologicalniche(UVUH2014).Coloradopopulationswillencounter
ClimateChangeVulnerabilityAssessmentforColoradoBLM345
theRoanPlateau,aneast‐westtrendingescarpment,whichpresentsanaturalelevational,
environmentalandhabitatbarrierthatrestrictstheabilityofthisspeciestoshiftrange.
B2b)Distributionrelativetoanthropogenicbarriers.SomewhatIncrease.SomeColorado
populationsinwillbeinhibitedfromrangeshiftbyoilandgasdevelopment(FracFocusWells
2013),habitatconversiontohayagricultureandhabitatalterationbylivestock(USDA2012).
B3)Predictedimpactoflandusechangesresultingfromhumanresponsestoclimatechange.
Neutral.AlthoughportionsofwesternColoradohavehighpotentialforwindandsolarenergy
development,thespeciesisunlikelytobesignificantlyaffectedbymitigation‐relatedlanduse
changesthatmayoccurwithinitscurrentand/orpotentialfuturerange(NRDC2011).
C1)Dispersalandmovements.Somewhatincrease.Similartorelatedspecies,thecylindricaland
corkyseedsofAmsoniajonesiimaybedispersedbywater.Dispersalbywaterishighly
unpredictableandundocumented(VittozandEngler2007)butingeneralmostplantseedsdonot
dispersefartherthan100m(Cainetal.2000).
C2ai)Predictedsensitivitytotemperature:historicthermalniche.Neutral.Consideringthe
meanseasonaltemperaturevariationovertherangeofthisspecies,Amsoniajonesiihas
experiencedaveragetemperaturevariation(57.1‐77°F)overthepast50years(NatureServe2012).
C2aii)Predictedsensitivitytotemperature:physiologicalthermalniche.Somewhatdecrease.
Thisspeciesisnotrestrictedtocoolorcoldenvironmentsandshowsapreferencefor
environmentstowardthewarmerendofthespectrum.
C2bi) Predictedsensitivitytochangesinprecipitation,hydrology,ormoistureregime:
historicalhydrologicalniche.Neutral.Consideringtherangeofmeanannualprecipitationacross
occupiedcells,A.jonesiihasexperiencedaverage(21‐40inches/509‐1,016mm)precipitation
variationinthepast50years(NatureServe2012).
C2bii)Predictedsensitivitytochangesinprecipitation,hydrology,ormoistureregime:
physiologicalhydrologicalniche.SomewhatIncrease.Speciesisfoundincoarse,sandysoilsoften
inthebottomsofdrawsanddrainages.Predictedclimatedryingduringthespringgrowingseason
willreducethisspeciesrecruitment,abundanceandhabitatsuitability.Longtermsurvivabilitymay
consequentlybediminishedeventhoughincreasedautumnmoisturemayenhancedispersaland
germinationpotential.Duringlatesummerandearlyautumn,A.jonesiiispredictedtobeexposed
toprecipitationdecreasesofupto3percentoverapproximately30percentofitsrangeand
increasesofupto6percentover70percentofitsrange.
C2c)Dependenceonaspecificdisturbanceregimelikelytobeimpactedbyclimatechange.
Increase.FirefrequenciesinthePinyon‐Juniperwoodlandsandsageanddesertshrublands
occupiedbythisspeciesareexpectedtoincreaseinthefuture,followingtrendsthatalreadyshow
increasedfirefrequencies,areaburnedandfireseverity(Littleetal.2009,Stephens2005,
Westerlingetal.2006,USFSnodate).
346ColoradoNaturalHeritageProgram©2015
C2d)Dependenceonice,ice‐edge,orsnowcoverhabitats.Neutral.Thisspeciesisnotrestricted
toordependentoniceorsnowcoverhabitats.
C3)Restrictiontouncommongeologicalfeaturesorderivatives.Somewhatdecrease.Speciesis
reportedtobewidelyadaptableinthenurserytrade,andisreportedtogrowonvarioussubstrates.
C4a)Dependenceonotherspeciestogeneratehabitat.Neutral.Thereisnoevidencethatthis
speciesdependsonotherspeciestogenerateitshabitat.
C4c)PollinatorVersatility.Neutral.InferredfromarelatedspeciesAmsoniakearneyanawhich
hasawidevarietyofpollinators(USFWS2013).
C4d)Dependenceonotherspeciesforpropaguledispersal.Neutral.Similartootherrelated
species,seedmorphologysuggeststhatthisspeciesmaydispersebywaterandisthusnotlikely
reliantonotherspeciesfordispersal.
C4e)FormspartofaninterspecificinteractionnotcoveredbyC4a‐d.Unknown.
C5a)Measuredgeneticvariation.Unknown.
C5b)Occurrenceofbottlenecksinrecentevolutionaryhistory.Unknown.
C6)Phenologicalresponsetochangingseasonaltemperatureandprecipitationdynamics.
Unknown.
D1)DocumentedResponsetoRecentClimateChange(e.g.,rangecontractionorphenology
mismatchwithcriticalresources).Unknown.
D2)ModeledFuture(2050)ChangeinRangeorPopulationSize.Increase.Rangewide
predictedfuturerangerepresentsa20percentto50percentdeclinerelativetocurrentrange
(UVUH2014).
D3)OverlapofModeledFuture(2050)RangewithCurrentRange.Neutral.Predictedfuture
rangeoverlapsthecurrentrangebygreaterthan60percentwithintheassessmentarea(UVUH
2014).
D4)OccurrenceofProtectedAreasinModeledFuture(2050)Distribution.Somewhat
Increase.Fivetothirtypercentofthemodeledfuturedistributionwithintheassessmentareais
encompassedbyoneormoreprotectedareas(USDI2014).
Literature Cited
Cain,M.L.,B.G.Milligan,andA.E.Strand.2000.Long‐distanceSeedDispersalinPlantPopulations.AmericanJournalof
Botany87(9):1217–1227.
ColoradoNaturalHeritageProgram.1997+.ColoradoRarePlantGuide.www.cnhp.colostate.edu.Latestupdate:June30,
2014.
ClimateChangeVulnerabilityAssessmentforColoradoBLM347
ColoradoNaturalHeritageProgram(CNHP).2014.BiodiversityTrackingandConservationSystem(BIOTICS).Colorado
NaturalHeritageProgram,ColoradoStateUniversity,FortCollins.
Littell,J.,D.McKenzie,D.Peterson,andA.Westerling.2009.ClimateandwildfireareaburnedinwesternU.S.
ecoprovinces,1916‐2003.EcologicalApplications19:1003‐1021
NatureServe2012.ClimateChangeVulnerabilityAssessmentTool,version2.1.Availableonlineat
https://connect.natureserve.org/science/climate‐change/ccvi.
NatureServe.2014.NatureServeExplorer:Anonlineencyclopediaoflife[webapplication].Version7.1.NatureServe,
Arlington,Virginia.Availablehttp://explorer.natureserve.org.
NRDCRenewableEnergyMapNaturalResourcesDefenseCounsel.2011.RenewableenergyforAmerica:harvestingthe
benefitsofhomegrown,renewableenergy.Online.Available:http://www.nrdc.org/energy/renewables/energymap.asp
(accessed2014).
Stephens,S.L.2005.ForestfirecausesandextentonUnitedStatesForestServicelands.InternationalJournalofWildland
Fire14:213‐222.
U.S.DepartmentofAgriculture(USDA).2012.2012CensusofAgriculture.Availableat:
http://www.agcensus.usda.gov/index.php
U.S.D.A.ForestService(USFS).NoDate.Pinyon‐JuniperNaturalRangeofVariation.Availableat:
http://www.fs.usda.gov/Internet/FSE_DOCUMENTS/stelprdb5434337.pdf.
U.S.DepartmentoftheInterior(USDI),U.S.GeologicalSurvey.2014.NationalGapAnalysisProgram,ProtectedAreasData
Viewer.Availableat:http://gapanalysis.usgs.gov/padus/viewer/
U.S.FishandWildlifeService(USFWS).2013.AmsoniakearneyanaKearneyblue‐star5‐YearReview:Summaryand
Evaluation.ArizonaEcologicalServicesTucsonSub‐office,Tucson,Arizona.
UtahValleyUniversityHerbarium(UVUH).2014.Availableat:http://herbarium.uvu.edu/herbInfo.shtml
VittozP.andEnglerR.2007.Seeddispersaldistances:atypologybasedondispersalmodesandplanttraits.Botanica
Helvetica,117(2),109–124.DOI:10.1007/s00035‐007‐0797‐8
Westerling,A.L.,B.P.Bryant,H.K.Preisler,T.P.Holmes,H.G.Hidalgo,T.Das,andS.R.Shrestha.2011.Climatechangeand
growthscenariosforCaliforniawildfire.ClimaticChange109:445‐463.

348ColoradoNaturalHeritageProgram©2015
Aquilegiachrysanthavar.rydbergii
Goldencolumbine
G4T1Q/S1
Family:Ranunculaceae
Photo:SteveOlson
Climate Vulnerability Rank: Extremely Vulnerable
ThisColoradostate‐widevulnerabilityrankisbasedonthefollowing:1)restrictiontomoistmicro‐
habitatsincliffs,canyons,andseeps2)relianceonhawkmothsasamajorpollinator3)shortseed
dispersaldistances.
Distribution:KnownfromFremont,ElPaso,Jefferson,andLasAnimascounties.ThePlants
Database(USDANRCS2015)showsA.chrysanthavar.rydbergiiinArizona,Colorado,andNew
Mexico.TheFloraofNorthAmerica(Vol.3,1997)statesthatColoradopopulationshavebeencalled
A.chrysanthavar.rydbergiianddoesnotmentionNewMexicoorArizona.ReportsfromNew
MexicoandArizona(USDANRCS2015)areprobablyerroneous,possiblyoriginatingbecauseNM
andAZarelistedintherangeofvar.rydbergiiinthe1985NoticeofReviewforListingas
EndangeredorThreatenedSpecies.Thesereportshavenototherwisebeensubstantiated.Habitat:
Incanyonsandfoothillsalongstreamsorinrockyravines(Spackmanetal.1997,Weberand
Wittmann2012).Aquilegiachrysanthavar.rydbergiigrowsinorganicsoilsandhasalsobeen
observedingravelderivedfromgraniteparentmaterial.Oftenfoundnearthebaseofboulderson
thecanyonsidesandfloor,itmayalsogrowonseep‐fedrockyledges.Itgrowsinshadyandmoist
areasonslopesaboveacreek,alongthesidedrainages,andwithintheriparianareaofaperennial
stream.Elevation:5,000‐8,240feet.
EcologicalSystem:MountainStreams,SeepsandSprings,DouglasFir
ClimateChangeVulnerabilityAssessmentforColoradoBLM349
CCVI Scoring
B1)Exposuretosealevelrise.Neutral.
B2a)Distributionrelativetonaturalbarriers.Neutral.
B2b)Distributionrelativetoanthropogenicbarriers.Neutral.
B3)Impactoflandusechangesresultingfromhumanresponsestoclimatechange.Neutral.
C1)Dispersalandmovements.Increase.Seedslikelyfallclosetotheparentplant,anddonot
containspecializedstructuresfordispersal.
C2ai)Predictedsensitivitytotemperature:historicthermalniche.SomewhatIncrease.
Consideringthemeanseasonaltemperaturevariationovertherangeofthisspecies,Aquilegia
chrysanthavar.rydbergiihasexperiencedslightlylowerthanaveragetemperaturevariation(47.1‐
57°F)overthepast50years(NatureServe2012).
C2aii)Predictedsensitivitytotemperature:physiologicalthermalniche.Increase.This
speciesoccursincool,shaded,moisthabitatsthatmaybereducedifColoradobecomeswarmerand
drier,asprojectedinmanyclimatemodels.
C2bi) Predictedsensitivitytochangesinprecipitation,hydrology,ormoistureregime:
historicalhydrologicalniche.Increase.Consideringtherangeofmeanannualprecipitationacross
occupiedcellsinColorado,A.chrysanthavar.rydbergiihasexperiencedslightlylowerthanaverage
(15.56inches)precipitationvariationinthepast50years(NatureServe2012).
C2bii)Predictedsensitivitytochangesinprecipitation,hydrology,ormoistureregime:
physiologicalhydrologicalniche.GreatlyIncrease.Thisspeciesoccursincool,shadedareasin
cliffsandcanyons.Thesemicro‐habitatsoftencontainmoistsoilsandseasonalseepsthatmaybe
vulnerabletoclimatechange.
C2c)Dependenceonaspecificdisturbanceregimelikelytobeimpactedbyclimatechange.
Neutral.
C2d)Dependenceonice,ice‐edge,orsnowcoverhabitats.Neutral.Thisspeciesisnotrestricted
toordependentoniceorsnowcoverhabitats.
C3)Restrictiontouncommongeologicalfeaturesorderivatives.Somewhatdecrease.This
speciesoccursinseveralhabitattypes.
C4a)Dependenceonotherspeciestogeneratehabitat.Neutral.
C4c)PollinatorVersatility.SomewhatIncrease.Crepuscularhawkmothsserveasamajor
pollinatorforA.chrysanthavar.rydbergiiinthesouthwestU.S.andnorthernMexico(Miller1985).
C4d)Dependenceonotherspeciesforpropaguledispersal.Neutral.
350ColoradoNaturalHeritageProgram©2015
C4e)FormspartofaninterspecificinteractionnotcoveredbyC4a‐d.Neutral.
C5a)Measuredgeneticvariation.Unknown.
C5b)Occurrenceofbottlenecksinrecentevolutionaryhistory.Unknown.
C6)Phenologicalresponsetochangingseasonaltemperatureandprecipitationdynamics.
Unknown.
Literature Cited
ColoradoNaturalHeritageProgram.1997+.ColoradoRarePlantGuide.www.cnhp.colostate.edu.Latestupdate:June30,
2014.
ColoradoNaturalHeritageProgram(CNHP).2014.BiodiversityTrackingandConservationSystem(BIOTICS).Colorado
NaturalHeritageProgram,ColoradoStateUniversity,FortCollins.
Miller,R.B.HawkmothPollinationofAquilegiachrysantha(Ranunculaceae)inSouthernArizona.TheSouthwestern
Naturalist30(1):69‐76.
NatureServe2012.ClimateChangeVulnerabilityAssessmentTool,version2.1.Availableonlineat
https://connect.natureserve.org/science/climate‐change/ccvi.
NatureServe.2014.NatureServeExplorer:Anonlineencyclopediaoflife[webapplication].Version7.1.NatureServe,
Arlington,Virginia.Availablehttp://explorer.natureserve.org.Accessed2014.
Spackman,S.,B.Jennings,J.Coles,C.Dawson,M.Minton,A.Kratz,andC.Spurrier.1997.Coloradorareplantfieldguide.
PreparedforBureauofLandManagement,U.S.ForestServiceandU.S.FishandWildlifeServicebyColoradoNatural
HeritageProgram.
USDA,NRCS.2015.ThePLANTSDatabase(http://plants.usda.gov).NationalPlantDataTeam,Greensboro,NC27401‐
4901USA.
Weber,W.A.andR.C.Wittmann.2012.ColoradoFlora,EasternSlope,AFieldGuidetotheVascularPlants,FourthEdition.
Boulder,Colorado.532pp.

ClimateChangeVulnerabilityAssessmentforColoradoBLM351
Asclepiasuncialisssp.uncialis
Dwarfmilkweed
G3G4T2T3/S2
Family:Asclepiadaceae
Photo:SteveOlson
Climate Vulnerability Rank: Extremely Vulnerable
ThisColoradostate‐widerankisbasedonthefollowingfactors:1)lackofvariabilityinmean
annualprecipitationinthepast50years;2)shortseeddispersaldistances;3)croplandandurban
developmentmayactasabarriertoseeddispersal;and4)potentialforwindenergydevelopment
onColorado’seasternplains.
Distribution:Estimatedrangeis71,964squarekilometers(27,785squaremiles),calculatedinGIS
bydrawingaminimumconvexpolygonaroundtheknownoccurrences.Thereispotentiallyabout
40,000squaremilesofhabitatineasternColorado(althoughperhapsasmuchas50%ofthisarea
isnolongersuitablehabitat),roughly45%ofthetotalpotentialrangeofthespecies.Thecurrent
knowndistributionofAsclepiasuncialisssp.uncialisformsanarcalongtheflankoftheSouthern
RockyMountainsfromnortheasternColoradotosouthwesternNewMexicoandadjacent
southeasternArizona.CurrentlyknownfromnineColoradocounties(LasAnimas,Weld,KitCarson,
Huerfano,Pueblo,Otero,Prowers,Fremont,andElPaso),andhistoricallyknownfromatleasteight
additionalcounties(Arapaho,Adams,Baca,Bent,Cheyenne,Larimer,DenverandWashington).
OccurrencesareprimarilyinsoutheasternColorado.Habitat:Asclepiasuncialisssp.uncialisis
primarilyassociatedwithspeciestypicalofshortgrassprairie.Associatedvegetationiscomprised
mostlyofgrasses,withforbs,shrubs,andtreestypicallycomprisinglessthan15%ofthetotal
vegetationcover.Althoughplantsareoftenfoundatthebaseofescarpmentsormesas,thespecies
doesnotoccuronrockledgesoroutcroppings,andisabsentfromhighlydisturbedhabitatssuchas
sanddunes,erosionchannels,washslopes,andbadlands.Occurrencesareknownfromsoils
derivedfromavarietyofsubstrates,includingsandstone,limestone,andshale,butaremostoften
foundinsandyloamsoils.Itdoesnotoccurinpuresand.
Elevation:3890‐7730feet.
352ColoradoNaturalHeritageProgram©2015
EcologicalSystem:ShortgrassPrairie,Pinyon‐Juniper
CCVI Scoring
B1)Exposuretosealevelrise.Neutral.
B2a)Distributionrelativetonaturalbarriers.Neutral.
B2b)Distributionrelativetoanthropogenicbarriers.SomewhatIncrease.Croplandand
urban/ex‐urbandevelopmentintheshortgrassprairiemayactasbarriersforseeddispersal.
B3)Impactoflandusechangesresultingfromhumanresponsestoclimatechange.Increase.
AccordingtoDepartmentofEnergywindresourcemaps,theeasternquarterofColoradonearthe
NewMexicoandNebraskabordershasexcellentwindresources(DOE2004).Winddevelopment
couldresultinthelossofA.uncialisvar.uncialishabitat.
C1)Dispersalandmovements.SomewhatIncrease.Seedscontainatuftofsilkyhairstoaidin
winddispersal(Decker2006).
C2ai)Predictedsensitivitytotemperature:historicthermalniche.SomewhatDecrease.
Consideringthemeanseasonaltemperaturevariationforoccupiedcells,thespecieshas
experiencedgreaterthanaverage(>77°F/43.0°C)temperaturevariationinthepast50years.
C2aii)Predictedsensitivitytotemperature:physiologicalthermalniche.Neutral.Not
restrictedtocoolorcoldclimatesthatareprojectedtobelostduetoclimatechange.
C2bi) Predictedsensitivitytochangesinprecipitation,hydrology,ormoistureregime:
historicalhydrologicalniche.Increase.Consideringtherangeofmeanannualprecipitationacross
occupiedA.uncialisvar.uncialishabitat,thespecieshasexperiencedsmall(4‐10inches/100‐254
mm)precipitationvariationinthepast50years.
C2bii)Predictedsensitivitytochangesinprecipitation,hydrology,ormoistureregime:
physiologicalhydrologicalniche.Increase.
C2c)Dependenceonaspecificdisturbanceregimelikelytobeimpactedbyclimatechange.
Neutral.
C2d)Dependenceonice,ice‐edge,orsnowcoverhabitats.Neutral.Thisspeciesisnotrestricted
toordependentoniceorsnowcoverhabitats.
C3)Restrictiontouncommongeologicalfeaturesorderivatives.Neutral.Occurrencesare
knownfromsoilsderivedfromavarietyofsubstrates,includingsandstone,limestone,andshale,
butaremostoftenfoundinsandyloamsoils(CNHP2014;Decker2006).Itdoesnotoccurinpure
sand.
C4a)Dependenceonotherspeciestogeneratehabitat.Neutral.Thereisnoevidencethatthis
speciesisdependentonotherspeciestogeneratehabitat.
ClimateChangeVulnerabilityAssessmentforColoradoBLM353
C4c)PollinatorVersatility.Neutral.Likelytobepollinatedbygeneralistspecies(Decker2006).
C4d)Dependenceonotherspeciesforpropaguledispersal.Neutral.
C4e)FormspartofaninterspecificinteractionnotcoveredbyC4a‐d.Neutral.
C5a)Measuredgeneticvariation.Unknown.
C5b)Occurrenceofbottlenecksinrecentevolutionaryhistory.Unknown.
C6)Phenologicalresponsetochangingseasonaltemperatureandprecipitationdynamics.
Unknown.
Literature Cited
ColoradoNaturalHeritageProgram.1997+.ColoradoRarePlantGuide.www.cnhp.colostate.edu.Latestupdate:June30,
2014.
ColoradoNaturalHeritageProgram(CNHP).2014.BiodiversityTrackingandConservationSystem(BIOTICS).Colorado
NaturalHeritageProgram,ColoradoStateUniversity,FortCollins.
Decker,K.2006.AsclepiasuncialisGreene(wheelmilkweed):atechnicalconservationassessment.[Online].USDAForest
Service,RockyMountainRegion.Available:http://www.fs.fed.us/r2/projects/scp/assessments/asclepiasuncialis.pdf
DepartmentofEnergy(DOE).2004.WINDExchange.ColoradoWindResourceMap.Availableonlineat
http://apps2.eere.energy.gov/wind/windexchange/wind_resource_maps.asp?stateab=co.AccessedFeb2,2015.
NatureServe2012.ClimateChangeVulnerabilityAssessmentTool,version2.1.Availableonlineat
https://connect.natureserve.org/science/climate‐change/ccvi.
NatureServe.2014.NatureServeExplorer:Anonlineencyclopediaoflife[webapplication].Version7.1.NatureServe,
Arlington,Virginia.Availablehttp://explorer.natureserve.org.Accessed2014.

354ColoradoNaturalHeritageProgram©2015
Astragalusanisus
Gunnisonmilkvetch
G2G3/S2S3
Family:Fabaceae
Photo:LoriBrummer
Climate Vulnerability Rank: Extremely Vulnerable
ThisColoradostate‐widerankisbasedonthefollowingfactors:1)highmountainranges
surroundingA.anisuspopulationscreatenaturalbarrierstodispersal;2)probablelimitedseed
dispersaldistances;3)potentialgeothermalenergydevelopmentintheGunnisonBasin;4)species
hasexperiencedasmallrangeofprecipitationinthelast50yearsand5)possiblyrelianceon
nodulization.
Distribution:ThespeciesentireglobalrangeiscontainedwithintheupperGunnisonBasin,in
GunnisonandSaguachecounties,Colorado.Estimatedrangeis1,962squarekilometers(757
squaremiles),calculatedinGISin2008bytheColoradoNaturalHeritageProgrambydrawinga
minimumconvexpolygonaroundtheknownoccurrences.Habitat:Drygravellyflatsandhillsides,
insandyclaysoilsoverlyinggraniticbedrock,usuallyamongorunderlowsagebrush.Elevation:
7500‐8500feet.
EcologicalSystem:Sagebrush
CCVI Scoring
B1)Exposuretosealevelrise.Neutral.
B2a)Distributionrelativetonaturalbarriers.SomewhatIncrease.Rangeshiftinresponseto
climatechangeisinhibitedbyhighmountainrangesthatsurroundtheGunnisonBasin.
ClimateChangeVulnerabilityAssessmentforColoradoBLM355
B2b)Distributionrelativetoanthropogenicbarriers.SomewhatIncreaseUrbanandexurban
developmentintheGunnisonBasinactascurrentandpotentialfuturebarrierstoA.anisus
movement.
B3)Impactoflandusechangesresultingfromhumanresponsestoclimatechange.Increase.
GeothermaldevelopmentpotentialishighintheGunnisonBasin,andifdevelopmentincreasedin
theBasin,itcouldfragmenthabitatintheBasin(USFWS2014).
C1)Dispersalandmovements.Increase.Seedslikelyfallclosetoparentplant,anddonotcontain
specializedstructurestoaidindispersal.
C2ai)Predictedsensitivitytotemperature:historicthermalniche.SomewhatDecrease.
Consideringthemeanseasonaltemperaturevariationforoccupiedcells,A.anisushasexperienced
greaterthanaverage(>77°F/43.0°C)temperaturevariationinthepast50years(NatureServe
2012).
C2aii)Predictedsensitivitytotemperature:physiologicalthermalniche.Neutral.Basedon
fieldobservations,thisplantiswelladaptedtodroughtandtemperatureextremes(Johnston,pers.
comm.2011).
C2bi)Predictedsensitivitytochangesinprecipitation,hydrology,ormoistureregime:
historicalhydrologicalniche.Increase.Thespecieshasexperiencedsmall(4‐10inches/100‐254
mm)precipitationvariationinthepast50years.
C2bii)Predictedsensitivitytochangesinprecipitation,hydrology,ormoistureregime:
physiologicalhydrologicalniche.SomewhatIncrease.Speciesissomewhatdependentona
stronglyseasonalhydrologicregimeorlocalizedmoistureregimethatishighlyvulnerabletoloss
orreductionwithclimatechange.Precipitationamountsarefairlyevenlydistributedthroughout
theseasons,withsomewhatmoremoistureoccurringduringthe“monsoon”seasonofJulyand
August(DeckerandAnderson2004).
C2c)Dependenceonaspecificdisturbanceregimelikelytobeimpactedbyclimatechange.
SomewhatIncrease.Astragalusanisusrequiresahighqualitymatrixcommunityofsagebrush
shrublandorpinyon‐juniperwoodlandswhichdependonanaturalfireregimetomaintain
appropriatevegetationstructure(NatureServe2014)Further,modeledfuturechangesinfire
probabilityandofvegetationpatternsshowincreasedprobabilityoffirethroughouttheregion
occupiedbythisspecies(Krawchuketal.2009).
C2d)Dependenceonice,ice‐edge,orsnowcoverhabitats.Neutral.Thisspeciesisnotrestricted
toordependentoniceorsnowcoverhabitats.
C3)Restrictiontouncommongeologicalfeaturesorderivatives.Neutral.
C4a)Dependenceonotherspeciestogeneratehabitat.Neutral.Thereisnoevidencethatthis
speciesisdependentonotherspeciestogeneratehabitat.
C4c)PollinatorVersatility.Neutral.Nodata,forcedscore.
356ColoradoNaturalHeritageProgram©2015
C4d)Dependenceonotherspeciesforpropaguledispersal.Neutral.Nodata,forcedscore.
C4e)FormspartofaninterspecificinteractionnotcoveredbyC4a‐d.SomewhatIncrease.
AlthoughAstragalusanisushasnotbeeninvestigatedfornodulization,noduleshavebeenreported
forseveralotherspeciesinthesubgroupArgophylii(A.crassicarpus,A.missouriensis,A.mollissimus,
andA.purshii),soitispossiblethatA.anisusalsopossessesthisability(DeckerandAnderson
2004).
C5a)Measuredgeneticvariation.Unknown.
C5b)Occurrenceofbottlenecksinrecentevolutionaryhistory.Unknown.
C6)Phenologicalresponsetochangingseasonaltemperatureandprecipitationdynamics.
Unknown.
Literature Cited
ColoradoNaturalHeritageProgram.1997+.ColoradoRarePlantGuide.www.cnhp.colostate.edu.Latestupdate:June30,
2014.
ColoradoNaturalHeritageProgram(CNHP).2014.BiodiversityTrackingandConservationSystem(BIOTICS).Colorado
NaturalHeritageProgram,ColoradoStateUniversity,FortCollins.
Decker,K.andD.G.Anderson.2004.AstragalusanisusM.E.Jones(Gunnisonmilkvetch):atechnicalconservation
assessment.[Online].USDAForestService,RockyMountainRegion.Available:
http://www.fs.fed.us/r2/projects/scp/assessments/astragalusanisus.pdf.[May5,2011].
Johnston,B.2011.PersonalcommunicationatGunnisonClimateChangeWorkshop,May13,2011.Gunnison,Colorado.
KrawchukM.A,M.A.Moritz,M‐A.Parisien,J.VanDorn,K.Hayhoe.2009.GlobalPyrogeography:theCurrentandFuture
DistributionofWildfire.PLoSONE4(4):e5102doi:10.1371/journal.pone.0005102.Availableat:
http://www.plosone.org/article/info%3Adoi%2F10.1371%2Fjournal.pone.0005102#pone‐0005102‐g002
NatureServe2012.ClimateChangeVulnerabilityAssessmentTool,version2.1.Availableonlineat
https://connect.natureserve.org/science/climate‐change/ccvi.
NatureServe.2014.NatureServeExplorer:Anonlineencyclopediaoflife[webapplication].Version7.1.NatureServe,
Arlington,Virginia.Availablehttp://explorer.natureserve.org.Accessed2014.
U.S.FishandWildlifeService(USFWS).2014.FinalRule,EndangeredandThreatenedWildlifeandPlants;Threatened
StatusforGunnisonSage‐Grouse.FederalRegisterVol79,No.224,Nov.20,2014.DepartmentoftheInterior.

ClimateChangeVulnerabilityAssessmentforColoradoBLM357
Astragalusdebequaeus
DeBequemilkvetch
G2/S2
Family:Fabaceae
Photo:PeggyLyon
Climate Vulnerability Rank: Extremely Vulnerable
ThisColoradostate‐widerankisbasedonthefollowingfactors:1)Astragalusdebequaeushabitatis
surroundedbyanthropogenicandnaturalbarriersthatmayinhibitrangeshift2)potentialincrease
innaturalgasdevelopmentinA.debequaeushabitat;3)A.debequaeushasexperiencedasmall
rangeinmeanannualprecipitationoverthelast50years;4)seeddispersaldistancesareprobably
fairlylimited;5)potentialsymbioticrelationshipwithroot‐nodulatingbacteria.
Distribution:KnownfromDelta,GarfieldandMesacounties,intheColoradoRiverValleynear
DeBeque.Theplant'srangeevidentlycorrespondstotheextentoftheAtwellGulchMemberofthe
WasatchFormation.Estimatedrangeis1,736squarekilometers(670squaremiles),calculatedin
2008bytheColoradoNaturalHeritagePrograminGISbydrawingaminimumconvexpolygon
aroundtheknownoccurrences.Habitat:Astragalusdebequaeusoccursinvari‐colored,fine
textured,seleniferous,andapparentlysalinesoilsoftheWasatchFormation‐AtwellGulchMember
(Welsh1985).Itisfoundinareassurroundedbypinyon‐juniperwoodlandsanddesertshrub
(Scheck1994).Astragalusdebequaeusisfoundonbarrenoutcropsofdarkclayinterspersedwith
lensesofsandstone.Theplantsoccuronsandyspots.Plantsaremostlyclusteredontoeslopesand
alongdrainages,butmanyoccuronsteepsideslopes.Soilsareclayeybutlitteredwithsandstone
fragments.Elevation:4950‐6680feet.
EcologicalSystem:Barrens,Pinyon‐Juniper,DesertShrub,Sagebrush
CCVI Scoring
B1)Exposuretosealevelrise.Neutral.
358ColoradoNaturalHeritageProgram©2015
B2a)Distributionrelativetonaturalbarriers.Increase.Rangeshiftinresponsetoclimate
changeisinhibitedbyunsuitablegeologyandhighmountainhabitatsthatwouldnotcontain
suitablehabitatforthisspecies(USGS2004).
B2b)Distributionrelativetoanthropogenicbarriers.SomewhatIncrease.Extensivehabitat
alterationduetooilandgasextractioninandaroundhabitatoccupiedbythisspecies(FracFocus
Wells2013)inhibitsrangeshift.Additionally,muchofthelandscapesurroundingoccurrencesofA.
debequaeushasbeenalteredbylivestockgrazing(CNHP2014).
B3)Impactoflandusechangesresultingfromhumanresponsestoclimatechange.Increase.
ThehabitatofA.debequaeushasahighpotentialfornaturalgasextraction,andmoderatepotential
forsolarandwindenergydevelopment(Grunauetal.2011;NRDC2011).
C1)Dispersalandmovements.Increase.Seeddispersalislikelyfairlylimited,consideringthatA.
debequaeusseedsdonotcontainanyspecializedstructurestoaidindispersal.
C2ai)Predictedsensitivitytotemperature:historicthermalniche.SomewhatDecrease.
Consideringthemeanseasonaltemperaturevariationforoccupiedcells,A.debequaeushas
experiencedgreaterthanaverage(>77°F/43.0°C)temperaturevariationinthepast50years.
C2aii)Predictedsensitivitytotemperature:physiologicalthermalniche.Neutral.A.
debequaeusoccupiesopensitesoverawiderangeofelevations(CNHP2014)withtemperatures
thatvaryadiabaticallywithelevation,suggestingthatthisspeciesisnotlimitedtocool
environments.
C2bi) Predictedsensitivitytochangesinprecipitation,hydrology,ormoistureregime:
historicalhydrologicalniche.Increase.Consideringtherangeofmeanannualprecipitationacross
occupiedcells,A.debequaeushasexperiencedsmall(4‐10inches/100‐254mm)precipitation
variationinthepast50years.
C2bii)Predictedsensitivitytochangesinprecipitation,hydrology,ormoistureregime:
physiologicalhydrologicalniche.Increase.Climatemodelsprojecthottertemperaturesfor
Colorado,withtrendstowardmoreseveresoil‐moisturedroughtconditionsinColorado(Lukaset
al.2014).Warmertemperatureswillresultinhigherevapotranspirationratesforplants.A.
debequaeusoccursinasemi‐aridclimatewithanaverageof11.33inchesofprecipitationperyear
(WesternRegionalClimateCenter2015).Althoughtolerancelimitsforlackofmoistureare
unknownforthisspecies,ahotterclimatecombinedwithhigherevapotranspirationmayresultin
stressfulconditionsforA.debequaeus.
C2c)Dependenceonaspecificdisturbanceregimelikelytobeimpactedbyclimatechange.
Neutral.
C2d)Dependenceonice,ice‐edge,orsnowcoverhabitats.Neutral.Thisspeciesisnotrestricted
toordependentoniceorsnowcoverhabitats.
C3)Restrictiontouncommongeologicalfeaturesorderivatives.SomewhatIncrease.Although
thisspeciesoccursinseveralhabitattypesincludingbarrens,pinyon‐juniper,desertshrub,and
ClimateChangeVulnerabilityAssessmentforColoradoBLM359
sagebrush,ithasapreferenceforbarrenoutcropsofdarkclaysoilsoftheAtwellGulchMemberof
the.WasatchFormation‐.
C4a)Dependenceonotherspeciestogeneratehabitat.Neutral.Thereisnoevidencethatthis
speciesisdependentonotherspeciestogeneratehabitat.
C4c)PollinatorVersatility.Neutral.AllAstragalusspeciesareranked‘Neutral’basedonUSFS
speciesassessmentsthatindicateseveralwesternAstragalusspeciesarevisitedbyover20species
ofbees(DeckerandAnderson2004).
C4d)Dependenceonotherspeciesforpropaguledispersal.Neutral.
C4e)FormspartofaninterspecificinteractionnotcoveredbyC4a‐d.SomewhatIncrease.
Astragalus.debequaeushasnotbeeninvestigatedfornodulization.However,noduleshavebeen
reportedforseveralotherspeciesinthesubgroupArgophylii(A.crassicarpus,A.missouriensis,A.
mollissimus,andA.purshii),soitispossiblethatA.equisolensisalsopossessesthisability(Decker
andAnderson2004).
C5a)Measuredgeneticvariation.Unknown.
C5b)Occurrenceofbottlenecksinrecentevolutionaryhistory.Unknown.
C6)Phenologicalresponsetochangingseasonaltemperatureandprecipitationdynamics.
Unknown.
Literature Cited
ColoradoNaturalHeritageProgram.1997+.ColoradoRarePlantGuide.www.cnhp.colostate.edu.Latestupdate:June30,
2014.
ColoradoNaturalHeritageProgram(CNHP).2014.BiodiversityTrackingandConservationSystem(BIOTICS).Colorado
NaturalHeritageProgram,ColoradoStateUniversity,FortCollins.
Decker,K.andD.G.Anderson.(2004,April21).AstragalusanisusM.E.Jones(Gunnisonmilkvetch):atechnical
conservationassessment.[Online].USDAForestService,RockyMountainRegion.Available:
http://www.fs.fed.us/r2/projects/scp/assessments/astragalusanisus.pdf.[May5,2011].
FracFocusWells.2013.MapProvidedbyFracTrackerAllianceonFracTracker.org.Availableat:
http://www.fractracker.org/map/national/
Lukas,J.,J.Barsugli,N.Doesken,I.Rangwala,andK.Wolter2014.ClimateChangeinColorado,ASynthesistoSupport
WaterResourcesManagementandAdaptation,SecondEdition.Availableat:
http://wwa.colorado.edu/climate/co2014report/.Accessed:2014.
NatureServe2012.ClimateChangeVulnerabilityAssessmentTool,version2.1.Availableonlineat
https://connect.natureserve.org/science/climate‐change/ccvi.
NatureServe.2014.NatureServeExplorer:Anonlineencyclopediaoflife[webapplication].Version7.1.NatureServe,
Arlington,Virginia.Availablehttp://explorer.natureserve.org.Accessed2014.
360ColoradoNaturalHeritageProgram©2015
NRDCRenewableEnergyMapNaturalResourcesDefenseCounsel.2011.RenewableenergyforAmerica:harvestingthe
benefitsofhomegrown,renewableenergy.Online.Available:http://www.nrdc.org/energy/renewables/energymap.asp
(accessed2014).
Scheck,C.1994.SpecialStatusPlantsHandbookGlenwoodSpringsResourceArea.Unpublishedreportpreparedforthe
BureauofLandManagement,GlenwoodSprings,CO.
USGSNationalGapAnalysisProgram.2004.ProvisionalDigitalLandCoverMapfortheSouthwesternUnitedStates.
Version1.0.RS/GISLaboratory,CollegeofNaturalResources,UtahStateUniversity.
Welsh,S.L.1985.NewspeciesofAstragalus(Leguminosae)fromMesaCounty,Colorado.GreatBasinNaturalist45(1):31‐
33.
WesternRegionalClimateCenter.2015.AverageannualprecipitationforGrandJunction,Colorado.
http://www.wrcc.dri.edu/cgi‐bin/cliMAIN.pl?co3488.AccessedFeb24,2015.PeriodofRecord:1900to2015.

ClimateChangeVulnerabilityAssessmentforColoradoBLM361
Astragalusequisolensis(Astragalusdesperatusvar.neeseae)
Horseshoemilkvetch
G5T1/S1
Family:Fabaceae
Photo:PeggyLyon
Climate Vulnerability Rank: Extremely Vulnerable
ThisColoradostate‐widerankisbasedon:1)A.equisolensishasexperiencedasmallrangeinmean
annualprecipitationoverthelast50years;2)seeddispersaldistancesareprobablyfairlylimited;
3)pinyon‐juniperhabitatsoccupiedbyA.equisolensismaybesubjecttoincreasedwildfiresand
decreasesinsoilmoistureundertheclimatechangeprojectionsofhottertemperatures;4)
potentialsymbioticrelationshipwithroot‐nodulatingbacteria.
Distribution:KnownfromonecountyinUtah(USDANRCS2015)andonecountyinColorado
(CNHP2014).Habitat:A.equisolensisisassociatedwithmixeddesertandsaltdesertshrub
vegetationcommunitiesthataregenerallydominatedbysagebrush,shadscaleandhorsebrush.The
populationsinMesaCountyareinanopenjuniper/blackbrushcommunityonrockyconvexslopes
withredsoils.Elevation:4520‐6030feet.
EcologicalSystem:Pinyon‐JuniperWoodlands
CCVI Scoring
B1)Exposuretosealevelrise.Neutral.
B2a)Distributionrelativetonaturalbarriers.SomewhatIncrease/Neutral.Rangeshiftin
responsetoclimatechangeisinhibitedbyunsuitablegeologyandhighmountainhabitatsthat
wouldnotcontainsuitablehabitatforthisspecies(USGS2004).
B2b)Distributionrelativetoanthropogenicbarriers.Neutral.
362ColoradoNaturalHeritageProgram©2015
B3)Impactoflandusechangesresultingfromhumanresponsestoclimatechange.
SomewhatIncrease.Habitatdisturbanceandalterationmayoccurwithincreaseddevelopmentof
uraniumminesinthearea.
C1)Dispersalandmovements.Increase.SeeddispersaldistancesarelikelyshortsinceAstragalus
seedsgenerallydonotcontainspecializedstructurestoaidindispersal.
C2ai)Predictedsensitivitytotemperature:historicthermalniche.Neutral.Consideringthe
meanseasonaltemperaturevariationforoccupiedcells,thisspecieshasexperiencedaverage(57.1
‐77°F/31.8‐43.0°C)temperaturevariationinthepast50years.
C2aii)Predictedsensitivitytotemperature:physiologicalthermalniche.Neutral.A.
equisolensisoccupiesopensitesoverawiderangeofelevations(CNHP2014)withtemperatures
thatvaryadiabaticallywithelevation,suggestingthatthisspeciesisnotlimitedtocool
environments.
C2bi) Predictedsensitivitytochangesinprecipitation,hydrology,ormoistureregime:
historicalhydrologicalniche.Increase.Consideringtherangeofmeanannualprecipitationacross
occupiedcells,thespecieshasexperiencedsmall(4‐10inches/100‐254mm)precipitation
variationinthepast50years.
C2bii)Predictedsensitivitytochangesinprecipitation,hydrology,ormoistureregime:
physiologicalhydrologicalniche.Increase.Climatemodelsprojecthottertemperaturesfor
Colorado,withtrendstowardmoreseveresoil‐moisturedroughtconditionsinColorado(Lukaset
al.2014).Warmertemperatureswillresultinhigherevapotranspirationratesforplants.A.
equisolensisoccursinasemi‐aridclimatewithanaverageof8.7inchesofprecipitationperyear
(WesternRegionalClimateCenter2015).Althoughtolerancelimitsforlackofmoistureare
unknownforthisspecies,ahotterclimatecombinedwithhigherevapotranspirationmayresultin
stressfulconditionsforA.equisolensis.
C2c)Dependenceonaspecificdisturbanceregimelikelytobeimpactedbyclimatechange.
SomewhatIncrease.A.equisolensisoccursinpinyon‐juniperhabitats.Thesehabitatsaremorelikely
toburnwithincreasedtemperaturesandanincreaseinweedyspeciesthatcomprisethe
understory,suchascheatgrass.
C2d)Dependenceonice,ice‐edge,orsnowcoverhabitats.Neutral.Thisspeciesisnotrestricted
toordependentoniceorsnowcoverhabitats.
C3)Restrictiontouncommongeologicalfeaturesorderivatives.Neutral.
C4a)Dependenceonotherspeciestogeneratehabitat.Neutral.Thereisnoevidencethatthis
speciesisdependentonotherspeciestogeneratehabitat.
C4c)PollinatorVersatility.Neutral.AllAstragalusspeciesareranked‘Neutral’basedonUSFS
speciesassessmentsthatindicateseveralwesternAstragalusspeciesarevisitedbyover20species
ofbees(DeckerandAnderson2004).
ClimateChangeVulnerabilityAssessmentforColoradoBLM363
C4d)Dependenceonotherspeciesforpropaguledispersal.Neutral.
C4e)FormspartofaninterspecificinteractionnotcoveredbyC4a‐d.SomewhatIncrease.
Astragalusequisolensishasnotbeeninvestigatedfornodulization.However,noduleshavebeen
reportedforseveralotherspeciesinthesubgroupArgophylii(A.crassicarpus,A.missouriensis,A.
mollissimus,andA.purshii),soitispossiblethatA.equisolensisalsopossessesthisability(Decker
andAnderson2004).
C5a)Measuredgeneticvariation.Unknown.
C5b)Occurrenceofbottlenecksinrecentevolutionaryhistory.Unknown.
C6)Phenologicalresponsetochangingseasonaltemperatureandprecipitationdynamics.
Unknown.
Literature Cited
ColoradoNaturalHeritageProgram.1997+.ColoradoRarePlantGuide.www.cnhp.colostate.edu.Latestupdate:June30,
2014.
ColoradoNaturalHeritageProgram(CNHP).2014.BiodiversityTrackingandConservationSystem(BIOTICS).Colorado
NaturalHeritageProgram,ColoradoStateUniversity,FortCollins.
Decker,K.andD.G.Anderson.2004.AstragalusanisusM.E.Jones(Gunnisonmilkvetch):atechnicalconservation
assessment.[Online].USDAForestService,RockyMountainRegion.Available:
http://www.fs.fed.us/r2/projects/scp/assessments/astragalusanisus.pdf.[May5,2011].
Lukas,J.,J.Barsugli,N.Doesken,I.Rangwala,andK.Wolter2014.ClimateChangeinColorado,ASynthesistoSupport
WaterResourcesManagementandAdaptation,SecondEdition.Availableat:
http://wwa.colorado.edu/climate/co2014report/.Accessed:2014.
NatureServe2012.ClimateChangeVulnerabilityAssessmentTool,version2.1.Availableonlineat
https://connect.natureserve.org/science/climate‐change/ccvi.
NatureServe.2014.NatureServeExplorer:Anonlineencyclopediaoflife[webapplication].Version7.1.NatureServe,
Arlington,Virginia.Availablehttp://explorer.natureserve.org.Accessed2014.
USDA,NRCS.2015.ThePLANTSDatabase(http://plants.usda.gov).NationalPlantDataTeam,Greensboro,NC27401‐
4901USA.
USGSNationalGapAnalysisProgram.2004.ProvisionalDigitalLandCoverMapfortheSouthwesternUnitedStates.
Version1.0.RS/GISLaboratory,CollegeofNaturalResources,UtahStateUniversity.
WesternRegionalClimateCenter.2015.AverageannualprecipitationforGateway,Colorado.
http://www.wrcc.dri.edu/cgi‐bin/cliMAIN.pl?co3246.AccessedFeb24,2015.PeriodofRecord:1947to2015.

364ColoradoNaturalHeritageProgram©2015
Astragalusmicrocymbus
Skiffmilkvetch
G1/S1
Family:Fabaceae
Photo:MichelleDePrenger‐Levin
Climate Vulnerability Rank: Extremely Vulnerable
ThisColoradostate‐widerankisbasedonthefollowingfactors:1)movementbarriers;2)poor
dispersalcapacity;3)restrictiontospecificgeologicfeatures;4)potentialfuturethreatsfrom
livestockgrazingandgeothermalenergydevelopment;5)potentialincreaseinfirefrequencyin
occupiedhabitat;6)potentialrelianceonseasonalmoistureregimesforfruitproduction.
Distribution:GunnisonCounty,andextendingintotheedgeofSaguacheCounty.Estimatedrange
is168squarekilometers,calculatedinGISbydrawingaminimumconvexpolygonaroundthe
knownoccurrences.Habitat:Opensagebrushorjuniper‐sagebrushcommunitiesonmoderately
steeptosteepslopes.Oftenfoundinrockyareaswithavarietyofsoilconditionsfromclayto
cobbles,graytoreddishincolor.Elevation:7600‐8400feet.
EcologicalSystem:Sagebrush,Pinyon‐Juniper
CCVI Scoring
B1)Exposuretosealevelrise.Neutral.
B2a)Distributionrelativetonaturalbarriers.SomewhatIncrease/Neutral.Rangeshiftin
responsetoclimatechangeisinhibitedbyunsuitablegeologyandhighmountainhabitatsthat
wouldnotcontainsuitablehabitatforthisspecies(USGS2004).
B2b)Distributionrelativetoanthropogenicbarriers.SomewhatIncrease/Neutral.The
followingpotentialfactorsthatmayaffectthehabitatorrangeofAstragalusmicrocymbusare(1)
Residentialandurbandevelopment;(2)recreation,roads,andtrails;(3)utilitycorridors;(4)
nonnativeinvasiveplants;(5)wildfire;(6)contourplowingandnonnativeseedings;(7)livestock,
ClimateChangeVulnerabilityAssessmentforColoradoBLM365
deerandelkuseofhabitat;(8)mining,oilandgasleasing;(9)climatechange;and(10)habitat
fragmentationanddegradation(USFWS2010).
B3)Impactoflandusechangesresultingfromhumanresponsestoclimatechange.Increase.
GeothermaldevelopmentpotentialishighintheGunnisonBasin,andifdevelopmentincreasedin
theBasin,itcouldaffectthelong‐termviabilityofA.microcymbuswithintheBasin(USFWS2014).
C1)Dispersalandmovements.Increase.Seeddispersalislikelyfairlylimited,consideringthatA.
microcymbusseedsdonotcontainanyspecializedstructurestoaidindispersal.
C2ai)Predictedsensitivitytotemperature:historicthermalniche.SomewhatDecrease.A.
microcymbushasexperiencedagreaterthanaveragetemperature(>70°F/43.0°C)variationinthe
past50years.
C2aii)Predictedsensitivitytotemperature:physiologicalthermalniche.SomewhatIncrease.
Speciesissomewhatrestrictedtocoolorcoldenvironmentsthatmaybelostasaresultofclimate
change.TemperaturesintheAstragalusmicrocymbusoccupiedhabitatcandipbelowfreezingany
monthoftheyear.Climatemodelspredictearlier,fastersnowmeltalongwithdecreasedsummer
precipitationandincreasedsummertemperatures(Barsugli2010).Thiswouldresultin
significantlyloweramountsofwaterstoredinthesoilsduringthesummer.
C2bi) Predictedsensitivitytochangesinprecipitation,hydrology,ormoistureregime:
historicalhydrologicalniche.Increase.Thespecieshasexperiencedsmall(4‐10inches/100‐254
mm)precipitationvariationinthepast50years.
C2bii)Predictedsensitivitytochangesinprecipitation,hydrology,ormoistureregime:
physiologicalhydrologicalniche.SomewhatIncrease.Precipitationinfluencesfruitproductionin
A.microcymbuswithadditionalfruitproducedinyearswithhigherthanaveragewinterprecipitation
(DePrenger‐Levinetal.2013).
C2c)Dependenceonaspecificdisturbanceregimelikelytobeimpactedbyclimatechange.
SomewhatIncrease.Sagebrushshrublandsandpinyon‐juniperhabitatsmayexperienceincreased
firefrequenciesduetoincreasedtemperatures.
C2d)Dependenceonice,ice‐edge,orsnowcoverhabitats.Neutral.Thisspeciesisnotrestricted
toordependentoniceorsnowcoverhabitats.
C3)Restrictiontouncommongeologicalfeaturesorderivatives.Neutral.
C4a)Dependenceonotherspeciestogeneratehabitat.Neutral.Thereisnoevidencethatthis
speciesisdependentonotherspeciestogeneratehabitat.
C4c)PollinatorVersatility.Neutral.AllAstragalusspeciesareranked‘Neutral’basedonUSFS
speciesassessmentsthatindicateseveralwesternAstragalusspeciesarevisitedbyover20species
ofbees(DeckerandAnderson2004).
C4d)Dependenceonotherspeciesforpropaguledispersal.Neutral.
366ColoradoNaturalHeritageProgram©2015
C4e)FormspartofaninterspecificinteractionnotcoveredbyC4a‐d.SomewhatIncrease.
AlthoughA.microcymbushasnotbeenstudiedfornodulization,manyspeciesofAstragalusform
mycorrhizalassociations.
C5a)Measuredgeneticvariation.Unknown.
C5b)Occurrenceofbottlenecksinrecentevolutionaryhistory.Unknown.
C6)Phenologicalresponsetochangingseasonaltemperatureandprecipitationdynamics.
Unknown.
Literature Cited
Barsugli,J.2010.HydrologicProjectionsfortheGunnisonBasin.PresentationatFollow‐upmeetingfortheClimate
ChangeAdaptationWorkshop.Gunnison,Colorado.
ColoradoNaturalHeritageProgram.1997+.ColoradoRarePlantGuide.www.cnhp.colostate.edu.Latestupdate:June30,
2014.
ColoradoNaturalHeritageProgram(CNHP).2014.BiodiversityTrackingandConservationSystem(BIOTICS).Colorado
NaturalHeritageProgram,ColoradoStateUniversity,FortCollins.
Decker,K.andD.G.Anderson.2004.AstragalusanisusM.E.Jones(Gunnisonmilkvetch):atechnicalconservation
assessment.[Online].USDAForestService,RockyMountainRegion.Available:
http://www.fs.fed.us/r2/projects/scp/assessments/astragalusanisus.pdf.[May5,2011].
DePrenger‐Levin,M.,J.M.RampNeale,T.A.GrantIII,C.DawsonandY.E.Baytok.2013.LifeHistoryandDemographyof
AstragalusmicrocymbusBarneby(Fabaceae).2013.NaturalAreasJournal,33(3):264‐275.
U.S.FishandWildlifeService(USFWS).2010.EndangeredandThreatenedWildlifeandPlants;TwelveMonthFindingon
aPetitiontoListAstragalusmicrocymbusandAstragalusschmolliaeasEndangeredorThreatened.FederalRegister:Vol.
75,No.240,December10,2010.
U.S.FishandWildlifeService(USFWS).2014.FinalRule,EndangeredandThreatenedWildlifeandPlants;Threatened
StatusforGunnisonSage‐Grouse.FederalRegisterVol79,No.224,Nov.20,2014.DepartmentoftheInterior.
USGSNationalGapAnalysisProgram.2004.ProvisionalDigitalLandCoverMapfortheSouthwesternUnitedStates.
Version1.0.RS/GISLaboratory,CollegeofNaturalResources,UtahStateUniversity.

ClimateChangeVulnerabilityAssessmentforColoradoBLM367
Astragalusnaturitensis
Naturitamilkvetch
G2G3/S2S3
Family:Fabaceae
Photo:B.Kuhn
Climate Vulnerability Rank: Extremely Vulnerable
ThisColoradostate‐widerankisbasedonthefollowingfactors1)barrierstomovement;2)limited
seeddispersalcapabilities;3)lackoftemperatureandprecipitationvariabilityinlast50years;4)
potentialdecreaseinsoilmoistureavailabilitywithincreasedtemperatures;5)restrictionto
specificgeologicfeaturesandsoiltypes;6)potentialforincreasedfirefrequencyinoccupiedA.
naturitensishabitat.
Distribution:KnownfromNewMexico,Utah,theNavajoNationandColorado(Garfield,Mesa,
Montezuma,Montrose,andSanMiguelcounties).Habitat:Astragalusnaturitensisoccurson
sandstoneledges,crevicesofsandstonebedrock,dryrockmesas,ledges,anddetritalslopesat
5000‐7000feet.Pinyon‐juniperwoodlandsinareaswithshallowsoilsoverexposedbedrock.
Usuallyitisinsmallsoilpocketsorrockcrevicesinsandstonepavementalongcanyonrims.
Sometimesitisfoundnearbyindeepersandysoilswithorwithoutsoil.Elevation:4830‐7030feet.
EcologicalSystem:CliffandCanyon,Pinyon‐Juniper,Sagebrush
CCVI Scoring
B1)Exposuretosealevelrise.Neutral.
B2a)Distributionrelativetonaturalbarriers.Increase/SomewhatIncrease.Highmountains,
unsuitablehabitat,andlargerivervalleys(Gunnison,Colorado,andSanMiguelrivers)mayactas
naturalbarriersthatinhibitrangeshiftsassociatedwithclimatechange.
368ColoradoNaturalHeritageProgram©2015
B2b)Distributionrelativetoanthropogenicbarriers.SomewhatIncrease/Neutral.Extensive
habitatalterationduetooilandgasextractioninWesternColorado(FracFocusWells2013)
inhibitsrangeshift.
B3)Impactoflandusechangesresultingfromhumanresponsestoclimatechange.Neutral.
C1)Dispersalandmovements.Increase.Seeddispersalislikelyfairlylimited,consideringthatA.
naturitensisseedsdonotcontainanyspecializedstructurestoaidindispersal.
C2ai)Predictedsensitivitytotemperature:historicthermalniche.SomewhatDecrease.
Consideringthemeanseasonaltemperaturevariationforoccupiedcells,A.naturitensishas
experiencedgreaterthanaverage(>77°F/43.0°C)temperaturevariationinthepast50years.
C2aii)Predictedsensitivitytotemperature:physiologicalthermalniche.Increase.
Consideringthemeanseasonaltemperaturevariationforoccupiedcells,A.naturitensishas
experiencedsmall(37‐47°F/20.8‐26.3°C)temperaturevariationinthepast50years.
C2bi) Predictedsensitivitytochangesinprecipitation,hydrology,ormoistureregime:
historicalhydrologicalniche.Increase.Consideringtherangeofmeanannualprecipitationacross
occupiedcells,thespecieshasexperiencedsmall(4‐10inches/100‐254mm)precipitation
variationinthepast50years.
C2bii)Predictedsensitivitytochangesinprecipitation,hydrology,ormoistureregime:
physiologicalhydrologicalniche.Increase.Climatemodelsprojecthottertemperaturesfor
Colorado,withtrendstowardmoreseveresoil‐moisturedroughtconditionsinColorado(Lukaset
al.2014).Warmertemperatureswillresultinhigherevapotranspirationratesforplants.A.
naturitensisoccursinasemi‐aridclimatewithanaverageof11.33inchesofprecipitationperyear
innearbyGrandJunction,CO(WesternRegionalClimateCenter2015).Althoughtolerancelimits
forlackofmoistureareunknownforthisspecies,ahotterclimatecombinedwithhigher
evapotranspirationmayresultinstressfulconditionsforA.naturitensis.
C2c)Dependenceonaspecificdisturbanceregimelikelytobeimpactedbyclimatechange.
SomewhatIncrease.Sagebrushshrublandsandpinyon‐juniperhabitatsmayexperienceincreased
firefrequenciesduetoincreasedtemperatures.
C2d)Dependenceonice,ice‐edge,orsnowcoverhabitats.Neutral.Thisspeciesisnotrestricted
toordependentoniceorsnowcoverhabitats.
C3)Restrictiontouncommongeologicalfeaturesorderivatives.SomewhatIncrease.
Astragalusnaturitensisoccursonsandstoneledges,crevicesofsandstonebedrock,dryrockmesas,
ledges,anddetritalslopesat5000‐7000feet(CNHP2014).Itisoftenfoundgrowinginshallowsoils
ontopofsandstoneledgesandslickrock,butoccasionalisfoundindeeper,sandysoils.
C4a)Dependenceonotherspeciestogeneratehabitat.Neutral.Thereisnoevidencethatthis
speciesisdependentonotherspeciestogeneratehabitat.
ClimateChangeVulnerabilityAssessmentforColoradoBLM369
C4c)PollinatorVersatility.Neutral.AllAstragalusspeciesareranked‘Neutral’basedonUSFS
speciesassessmentsthatindicateseveralwesternAstragalusspeciesarevisitedbyover20species
ofbees(DeckerandAnderson2004).
C4d)Dependenceonotherspeciesforpropaguledispersal.Neutral.
C4e)FormspartofaninterspecificinteractionnotcoveredbyC4a‐d.SomewhatIncrease.A.
naturitensishasnotbeeninvestigatedfornodulization.However,noduleshavebeenreportedfor
severalotherspeciesinthesubgroupArgophylii(A.crassicarpus,A.missouriensis,A.mollissimus,
andA.purshii),soitispossiblethatA.naturitensisalsopossessesthisability(DeckerandAnderson
2004).
C5a)Measuredgeneticvariation.Unknown.
C5b)Occurrenceofbottlenecksinrecentevolutionaryhistory.Unknown.
C6)Phenologicalresponsetochangingseasonaltemperatureandprecipitationdynamics.
Unknown.
Literature Cited
ColoradoNaturalHeritageProgram.1997+.ColoradoRarePlantGuide.www.cnhp.colostate.edu.Latestupdate:June30,
2014.
ColoradoNaturalHeritageProgram(CNHP).2014.BiodiversityTrackingandConservationSystem(BIOTICS).Colorado
NaturalHeritageProgram,ColoradoStateUniversity,FortCollins.
Decker,K.andD.G.Anderson.2004.AstragalusanisusM.E.Jones(Gunnisonmilkvetch):atechnicalconservation
assessment.[Online].USDAForestService,RockyMountainRegion.Available:
http://www.fs.fed.us/r2/projects/scp/assessments/astragalusanisus.pdf.[May5,2011].
FracFocusWells.2013.MapProvidedbyFracTrackerAllianceonFracTracker.org.Availableat:
http://www.fractracker.org/map/national/
Lukas,J.,J.Barsugli,N.Doesken,I.Rangwala,andK.Wolter2014.ClimateChangeinColorado,ASynthesistoSupport
WaterResourcesManagementandAdaptation,SecondEdition.Availableat:
http://wwa.colorado.edu/climate/co2014report/.Accessed:2014.
370ColoradoNaturalHeritageProgram©2015
Astragalusosterhoutii
Kremmlingmilkvetch
G1/S1
ListedEndangered
Family:Fabaceae
Photo:DeniseCulver
Climate Vulnerability Rank: Extremely Vulnerable
ThisColoradostate‐widerankisbasedonthefollowingfactors:1)barrierstomovement;2)limited
seeddispersaldistance;3)lackofvariationinannualprecipitationinthelast50years;4)potential
lackofsoilmoistureduetoprojectionsofhottertemperatures;5)potentialincreaseinfire
frequencyinsagebrushecosystems;6)restrictiontohighlyseleniferoussoilsanduniquegeologic
substrates6)potentialsymbioticrelationshipwithroot‐nodulatingbacteria.
Distribution:EndemictoGrandCounty,Colorado.Estimatedrangeis120squarekilometers,
calculatedinGISbydrawingaminimumconvexpolygonaroundtheknownoccurrences.
Impreciselyreportedoccurrencesarenotincluded.Habitat:Highlyseleniferoussoils(grayish‐
brownclay)derivedfromNiobraraShale;sometimesgrowingupthroughsagebrush.Elevation:
7370‐8000feet.
EcologicalSystem:Sagebrush
CCVI Scoring
B1)Exposuretosealevelrise.Neutral.
B2a)Distributionrelativetonaturalbarriers.SomewhatIncrease.AccordingtoSWReGAP
vegetationlayers,unsuitablehabitatandgeologysurroundingknownlocationsofA.osterhoutiimay
restrictrangeshiftsduetoclimatechange(USGS2004).
ClimateChangeVulnerabilityAssessmentforColoradoBLM371
B2b)Distributionrelativetoanthropogenicbarriers.Neutral.Housingdevelopment,motorized
recreationareas,oilandgasdrilling,androadsallcreatebarrierstomovementforA.osterhoutii.
B3)Impactoflandusechangesresultingfromhumanresponsestoclimatechange.
SomewhatIncrease.IncreasedoilandgasdrillingcouldleadtolossofindividualA.osterhoutii
plants,andincreasedhabitatfragmentationanddegradation.
C1)Dispersalandmovements.Increase.Seeddispersaldistancesarelikelysomewhatlimiteddue
tothelackofspecializedstructurestoaidindispersal.
C2ai)Predictedsensitivitytotemperature:historicthermalniche.SomewhatDecrease.
Consideringthemeanseasonaltemperaturevariationforoccupiedcells,thespecieshas
experiencedgreaterthanaverage(>77°F/43.0°C)temperaturevariationinthepast50years.
C2aii)Predictedsensitivitytotemperature:physiologicalthermalniche.Neutral.A.
osterhoutiiisnotlimitedtocoolorcoldhabitatsthatmaybelosttoclimatechange.Lessthan10%
ofsagebrushecosystemsinColoradoareprojectedtobeoutsideofitscurrentclimaticenvelope
(SeeEcosystemSectionofreport).
C2bi) Predictedsensitivitytochangesinprecipitation,hydrology,ormoistureregime:
historicalhydrologicalniche.Increase.Consideringtherangeofmeanannualprecipitationacross
occupiedcells,thespecieshasexperiencedsmall(4‐10inches/100‐254mm)precipitation
variationinthepast50years.
C2bii)Predictedsensitivitytochangesinprecipitation,hydrology,ormoistureregime:
physiologicalhydrologicalniche.SomewhatIncrease.Climatemodelsprojecthotter
temperaturesforColorado,withtrendstowardmoreseveresoil‐moisturedroughtconditionsin
Colorado(Lukasetal.2014).Warmertemperatureswillresultinhigherevapotranspirationrates
forplants.A.osterhoutiioccursinasemi‐aridclimatewithanaverageof11.88inchesof
precipitationperyear(WesternRegionalClimateCenter2015).Althoughtolerancelimitsforlack
ofmoistureareunknownforthisspecies,ahotterclimatecombinedwithhigher
evapotranspirationmayresultinstressfulconditionsforA.osterhoutii.
C2c)Dependenceonaspecificdisturbanceregimelikelytobeimpactedbyclimatechange.
SomewhatIncrease.ClimatemodelsprojecthottertemperaturesforColorado(Lukasetal.2014),
andthiscouldresultinincreasedfirefrequencyinsagebrushecosystems.
C2d)Dependenceonice,ice‐edge,orsnowcoverhabitats.Neutral.Thisspeciesisnotrestricted
toordependentoniceorsnowcoverhabitats.
C3)Restrictiontouncommongeologicalfeaturesorderivatives.SomewhatIncrease.Speciesis
restrictedtowhiteshaleoutcropsofNiobrara,Pierre,andTroublesomeFormationsinGrand
County(CNHP2014).Itismostoftenfoundgrowinginhighlyseleniferoussoils.
C4a)Dependenceonotherspeciestogeneratehabitat.Neutral.Thereisnoevidencethatthis
speciesisdependentonotherspeciestogeneratehabitat.
372ColoradoNaturalHeritageProgram©2015
C4c)PollinatorVersatility.Neutral.
C4d)Dependenceonotherspeciesforpropaguledispersal.Neutral.
C4e)FormspartofaninterspecificinteractionnotcoveredbyC4a‐d.SomewhatIncrease.A.
osterhoutiihasnotbeeninvestigatedfornodulization.However,noduleshavebeenreportedfor
severalotherspeciesinthesubgroupArgophylii(A.crassicarpus,A.missouriensis,A.mollissimus,
andA.purshii),soitispossiblethatA.osterhoutiialsopossessesthisability(DeckerandAnderson
2004).
C5a)Measuredgeneticvariation.Unknown.
C5b)Occurrenceofbottlenecksinrecentevolutionaryhistory.Unknown.
C6)Phenologicalresponsetochangingseasonaltemperatureandprecipitationdynamics.
Unknown.
Literature Cited
ColoradoNaturalHeritageProgram.1997+.ColoradoRarePlantGuide.www.cnhp.colostate.edu.Latestupdate:June30,
2014.
ColoradoNaturalHeritageProgram(CNHP).2014.BiodiversityTrackingandConservationSystem(BIOTICS).Colorado
NaturalHeritageProgram,ColoradoStateUniversity,FortCollins.
Decker,K.andD.G.Anderson.2004.AstragalusanisusM.E.Jones(Gunnisonmilkvetch):atechnicalconservation
assessment.[Online].USDAForestService,RockyMountainRegion.Available:
http://www.fs.fed.us/r2/projects/scp/assessments/astragalusanisus.pdf.[May5,2011].
Lukas,J.,J.Barsugli,N.Doesken,I.Rangwala,andK.Wolter2014.ClimateChangeinColorado,ASynthesistoSupport
WaterResourcesManagementandAdaptation,SecondEdition.Availableat:
http://wwa.colorado.edu/climate/co2014report/.Accessed:2014.
USGSNationalGapAnalysisProgram.2004.ProvisionalDigitalLandCoverMapfortheSouthwesternUnitedStates.
Version1.0.RS/GISLaboratory,CollegeofNaturalResources,UtahStateUniversity.
WesternRegionalClimateCenter.2015.AverageannualprecipitationforKremmling,Colorado.
http://www.wrcc.dri.edu/cgi‐bin/cliMAIN.pl?co3488.AccessedFeb24,2015.PeriodofRecord:1908to2015.

ClimateChangeVulnerabilityAssessmentforColoradoBLM373
Astragaluspiscator
FisherTowersmilkvetch
G2G3/S1
Family:Fabaceae
Photo:PeggyLyon
Climate Vulnerability Rank: Extremely Vulnerable
ThisColoradostate‐widerankisbasedonthefollowingfactors:1)A.piscatorhasexperienceda
verysmallrangeinmeanannualprecipitationoverthelast50years;2)seeddispersaldistances
areprobablyfairlylimited;3)potentialincreaseinuraniumandvanadiummininginA.piscator
habitat4)pinyon‐juniperhabitatsoccupiedbyA.piscatormaybesubjecttoincreasedwildfires
undertheclimatechangeprojectionsofhottertemperatures;5)potentiallackofavailablesoil
moistureunderprojectedclimatewarming;6)potentialsymbioticrelationshipwithroot‐
nodulatingbacteria.
Distribution:KnownfromoneoccurrenceinMesaCountyinColorado.AlsoknownfromUtah.
Habitat:Insandy,sometimesgypsiferoussoilsofvalleybenchesandgulliedfoothills.InGateway,it
isfoundonslightlygravellysoilswithmixedredandwhiteparticles.Inaddition,itwasoftenfound
onthesidesofdrygullies(Spackmanetal.1997).Elevation:4500‐5580feet.
EcologicalSystem:SandyAreas,DesertShrub,Pinyon‐Juniper
CCVI Scoring
B1)Exposuretosealevelrise.Neutral.
B2a)Distributionrelativetonaturalbarriers.Neutral.Thisspeciesisknownfromthe
Colorado/Utahborderinruggedcanyonlands.Nomountainrangesorlargerivervalleysoccurhere.
B2b)Distributionrelativetoanthropogenicbarriers.Neutral.Fewanthropogenicdisturbances
arepresentintheruggedcanyonsnearGateway,Colorado.Roads,railroads,andsparsehousing
374ColoradoNaturalHeritageProgram©2015
developmentarethemaindisturbanceslocatednearA.piscatorhabitat,buttheseoccupyafairly
smallfootprint.
B3)Impactoflandusechangesresultingfromhumanresponsestoclimatechange.Increase.
FutureincreasesinuraniumandvanadiumminingarepossiblewithinA.piscatorhabitat(CNHP
2014).
C1)Dispersalandmovements.Increase.Seedsdonotcontainspecializedstructurestoaidin
dispersal,andlikelyfallclosetoparentplant.
C2ai)Predictedsensitivitytotemperature:historicthermalniche.Neutral.Consideringthe
meanseasonaltemperaturevariationforoccupiedcells,A.piscatorhasexperiencedaverage(57.1‐
77°F/31.8‐43.0°C)temperaturevariationinthepast50years.
C2aii)Predictedsensitivitytotemperature:physiologicalthermalniche.Neutral.Thisspecies
isnotlimitedtocoolorcoldenvironments.Itoccursindry,uplandareasdominatedbypinyon‐
juniperanddesertshrubs.
C2bi) Predictedsensitivitytochangesinprecipitation,hydrology,ormoistureregime:
historicalhydrologicalniche.GreatlyIncrease.Consideringtherangeofmeanannual
precipitationacrossoccupiedcells,A.piscatorhasexperiencedverysmall(<4inches/100mm)
precipitationvariationinthepast50years.
C2bii)Predictedsensitivitytochangesinprecipitation,hydrology,ormoistureregime:
physiologicalhydrologicalniche.Increase.Climatemodelsprojecthottertemperaturesfor
Colorado,withtrendstowardmoreseveresoil‐moisturedroughtconditionsinColorado(Lukaset
al.2014).Warmertemperatureswillresultinhigherevapotranspirationratesforplants.A.piscator
occursinasemi‐aridclimatewithanaverageof8.7inchesofprecipitationperyear(Western
RegionalClimateCenter2015).Althoughtolerancelimitsforlackofmoistureareunknownforthis
species,ahotterclimatecombinedwithhigherevapotranspirationmayresultinstressful
conditionsforA.piscator.
C2c)Dependenceonaspecificdisturbanceregimelikelytobeimpactedbyclimatechange.
SomewhatIncrease.A.piscatoroccursinpinyon‐juniperhabitats.Thesehabitatsaremorelikelyto
burnwithincreasedtemperaturesandanincreaseinweedyspeciesthatcomprisetheunderstory,
suchascheatgrass.
C2d)Dependenceonice,ice‐edge,orsnowcoverhabitats.Neutral.Thisspeciesisnotrestricted
toordependentoniceorsnowcoverhabitats.
C3)Restrictiontouncommongeologicalfeaturesorderivatives.Neutral.
C4a)Dependenceonotherspeciestogeneratehabitat.Neutral.Thereisnoevidencethatthis
speciesisdependentonotherspeciestogeneratehabitat.
ClimateChangeVulnerabilityAssessmentforColoradoBLM375
C4c)PollinatorVersatility.Neutral.AllAstragalusspeciesareranked‘Neutral’basedonUSFS
speciesassessmentsthatindicateseveralwesternAstragalusspeciesarevisitedbyover20species
ofbees(DeckerandAnderson2004).
C4d)Dependenceonotherspeciesforpropaguledispersal.Neutral.
C4e)FormspartofaninterspecificinteractionnotcoveredbyC4a‐d.SomewhatIncrease.A.
piscatorhasnotbeeninvestigatedfornodulization.However,noduleshavebeenreportedfor
severalotherspeciesinthesubgroupArgophylii(A.crassicarpus,A.missouriensis,A.mollissimus,
andA.purshii),soitispossiblethatA.piscatoralsopossessesthisability(DeckerandAnderson
2004).
C5a)Measuredgeneticvariation.Unknown.
C5b)Occurrenceofbottlenecksinrecentevolutionaryhistory.Unknown.
C6)Phenologicalresponsetochangingseasonaltemperatureandprecipitationdynamics.
Unknown.
Literature Cited
ColoradoNaturalHeritageProgram.1997+.ColoradoRarePlantGuide.www.cnhp.colostate.edu.Latestupdate:June30,
2014.
ColoradoNaturalHeritageProgram(CNHP).2014.BiodiversityTrackingandConservationSystem(BIOTICS).Colorado
NaturalHeritageProgram,ColoradoStateUniversity,FortCollins.
Decker,K.andD.G.Anderson.2004.AstragalusanisusM.E.Jones(Gunnisonmilkvetch):atechnicalconservation
assessment.[Online].USDAForestService,RockyMountainRegion.Available:
http://www.fs.fed.us/r2/projects/scp/assessments/astragalusanisus.pdf.[Feb26,2015].
Lukas,J.,J.Barsugli,N.Doesken,I.Rangwala,andK.Wolter2014.ClimateChangeinColorado,ASynthesistoSupport
WaterResourcesManagementandAdaptation,SecondEdition.Availableat:
http://wwa.colorado.edu/climate/co2014report/.Accessed:2014.
Spackman,S.,B.Jennings,J.Coles,C.Dawson,M.Minton,A.Kratz,andC.Spurrier.1997.Coloradorareplantfieldguide.
PreparedforBureauofLandManagement,U.S.ForestServiceandU.S.FishandWildlifeServicebyColoradoNatural
HeritageProgram.
WesternRegionalClimateCenter.2015.AverageannualprecipitationforGateway,Colorado.
http://www.wrcc.dri.edu/cgi‐bin/cliMAIN.pl?co3246.AccessedFeb24,2015.PeriodofRecord:1947to2015.

376ColoradoNaturalHeritageProgram©2015
Astragalusrafaelensis
SanRafaelmilkvetch
G2G3/S1
Family:Fabaceae
Photo:PeggyLyon
Climate Vulnerability Rank: Extremely Vulnerable
ThisColoradostate‐widerankisbasedonthefollowingfactors:1)A.rafaelensishasexperienceda
verysmallrangeinmeanannualprecipitationoverthelast50years;2)seeddispersaldistances
areprobablyfairlylimited;3)pinyon‐juniperhabitatsoccupiedbyA.rafaelensismaybesubjectto
increasedwildfiresundertheclimatechangeprojectionsofhottertemperatures;5)potentiallack
ofavailablesoilmoistureunderprojectedclimatewarming;6)potentialsymbioticrelationship
withroot‐nodulatingbacteria.
Distribution:ThisisaNavajoBasinendemic;EmeryandlesscommonlyinGrandCounty,Utah
(Welshetal.1993),alsoinMontrose,MesaandLaPlatacountiesinColorado(CNHP1998).
Habitat:Gulliedhills,washes,andtalusundercliffs;inseleniferousclayey,silty,orsandysoils.
Sometimescolonialonroadcuts.ColoradoplantsarefoundonsoilsderivedfromtheMorrison
formation,evenwhenthishaswasheddownontoEntradaorChinleformations(Spackmanetal.
1997).Elevation:4720‐6700feet.
EcologicalSystem:Pinyon‐Juniper
CCVI Scoring
B1)Exposuretosealevelrise.Neutral.
B2a)Distributionrelativetonaturalbarriers.Increase.Rangeshiftinresponsetoclimate
changeisinhibitedbyunsuitablegeologyandhighmountainhabitatsthatwouldnotcontain
suitablehabitatforthisspecies(USGS2004).
ClimateChangeVulnerabilityAssessmentforColoradoBLM377
B2b)Distributionrelativetoanthropogenicbarriers.Neutral.Fewanthropogenicdisturbances
arepresentintheruggedcanyonsnearParadoxandNucla,Colorado.Roads,railroads,andsparse
housingdevelopmentarethemaindisturbanceslocatednearA.rafaelensishabitat,butthese
occupyafairlysmallfootprint.
B3)Impactoflandusechangesresultingfromhumanresponsestoclimatechange.Neutral.
C1)Dispersalandmovements.Increase.Seedsdonotcontainspecializedstructurestoaidin
dispersal,andlikelyfallclosetoparentplant.
C2ai)Predictedsensitivitytotemperature:historicthermalniche.Neutral.Consideringthe
meanseasonaltemperaturevariationforoccupiedcells,A.rafaelensishasexperiencedaverage
(57.1‐77°F/31.8‐43.0°C)temperaturevariationinthepast50years.
C2aii)Predictedsensitivitytotemperature:physiologicalthermalniche.Neutral.Thisspecies
isnotlimitedtocoolorcoldenvironments.Itoccursindrywashesandcliffbasesinareas
dominatedbypinyon‐juniper.
C2bi) Predictedsensitivitytochangesinprecipitation,hydrology,ormoistureregime:
historicalhydrologicalniche.GreatlyIncrease.Consideringtherangeofmeanannual
precipitationacrossoccupiedcells,A.rafaelensishasexperiencedverysmall(<4inches/100mm)
precipitationvariationinthepast50years.
C2bii)Predictedsensitivitytochangesinprecipitation,hydrology,ormoistureregime:
physiologicalhydrologicalniche.Increase.Climatemodelsprojecthottertemperaturesfor
Colorado,withtrendstowardmoreseveresoil‐moisturedroughtconditionsinColorado(Lukaset
al.2014).Warmertemperatureswillresultinhigherevapotranspirationratesforplants.A.
rafaelensisoccursinasemi‐aridclimatewithanaverageof11.73inchesofprecipitationperyear
(WesternRegionalClimateCenter2015).Althoughtolerancelimitsforlackofmoistureare
unknownforthisspecies,ahotterclimatecombinedwithhigherevapotranspirationmayresultin
stressfulconditionsforA.rafaelensis.
C2c)Dependenceonaspecificdisturbanceregimelikelytobeimpactedbyclimatechange.
SomewhatIncrease.A.rafaelensisoccursinpinyon‐juniperhabitats.Thesehabitatsaremorelikely
toburnwithincreasedtemperaturesandanincreaseinweedyspeciesthatcomprisethe
understory,suchascheatgrass.
C2d)Dependenceonice,ice‐edge,orsnowcoverhabitats.Neutral.Thisspeciesisnotrestricted
toordependentoniceorsnowcoverhabitats.
C3)Restrictiontouncommongeologicalfeaturesorderivatives.Neutral.
C4a)Dependenceonotherspeciestogeneratehabitat.Neutral.Thereisnoevidencethatthis
speciesisdependentonotherspeciestogeneratehabitat.
378ColoradoNaturalHeritageProgram©2015
C4c)PollinatorVersatility.Neutral.AllAstragalusspeciesareranked‘Neutral’basedonUSFS
speciesassessmentsthatindicateseveralwesternAstragalusspeciesarevisitedbyover20species
ofbees(DeckerandAnderson2004).
C4d)Dependenceonotherspeciesforpropaguledispersal.Neutral.
C4e)FormspartofaninterspecificinteractionnotcoveredbyC4a‐d.SomewhatIncrease.A.
rafaelensishasnotbeeninvestigatedfornodulization.However,noduleshavebeenreportedfor
severalotherspeciesinthesubgroupArgophylii(A.crassicarpus,A.missouriensis,A.mollissimus,
andA.purshii),soitispossiblethatA.rafaelensisalsopossessesthisability(DeckerandAnderson
2004).
C5a)Measuredgeneticvariation.Unknown.
C5b)Occurrenceofbottlenecksinrecentevolutionaryhistory.Unknown.
C6)Phenologicalresponsetochangingseasonaltemperatureandprecipitationdynamics.
Unknown.
Literature Cited
ColoradoNaturalHeritageProgram.1997+.ColoradoRarePlantGuide.www.cnhp.colostate.edu.Latestupdate:June30,
2014.
ColoradoNaturalHeritageProgram(CNHP).2014.BiodiversityTrackingandConservationSystem(BIOTICS).Colorado
NaturalHeritageProgram,ColoradoStateUniversity,FortCollins.
Decker,K.andD.G.Anderson.2004.AstragalusanisusM.E.Jones(Gunnisonmilkvetch):atechnicalconservation
assessment.[Online].USDAForestService,RockyMountainRegion.Available:
http://www.fs.fed.us/r2/projects/scp/assessments/astragalusanisus.pdf.[May5,2011].
Lukas,J.,J.Barsugli,N.Doesken,I.Rangwala,andK.Wolter2014.ClimateChangeinColorado,ASynthesistoSupport
WaterResourcesManagementandAdaptation,SecondEdition.Availableat:
http://wwa.colorado.edu/climate/co2014report/.Accessed:2014.
Spackman,S.,B.Jennings,J.Coles,C.Dawson,M.Minton,A.Kratz,andC.Spurrier.1997.Coloradorareplantfieldguide.
PreparedforBureauofLandManagement,U.S.ForestServiceandU.S.FishandWildlifeServicebyColoradoNatural
HeritageProgram.
USGSNationalGapAnalysisProgram.2004.ProvisionalDigitalLandCoverMapfortheSouthwesternUnitedStates.
Version1.0.RS/GISLaboratory,CollegeofNaturalResources,UtahStateUniversity.

ClimateChangeVulnerabilityAssessmentforColoradoBLM379
Astragalusripleyi
Ripley’smilkvetch
G3/S2
Family:Fabaceae

Photo:CourtesyofColoradoNaturalAreasProgram
Climate Vulnerability Rank: Extremely Vulnerable
ThisColoradostate‐widerankisbasedon:predictedprecipitationdecreases;highmountainsthat
actasnaturalbarriersandhabitatalterationthatresultsfromconversiontofarmland,andlivestock
grazing,whichactasanthropogenicbarrierstorangeshift;limitedseeddispersaldistance;
alterationtothenaturalfiredisturbanceregime;restrictiontoasomewhatuncommongeology;
andpollinatorlimitations.Suitablehabitatislikelytobereducedandreproductivesuccess
diminished.Climatemodelsprojectannualnetdryingthroughoutthisspeciesrange(NatureServe
2012)withresultingtrendstowardmoreseveresoil‐moisturedroughtconditionsinColorado
(Lukasetal.2014).
Distribution:AstragalusripleyihasbeenreportedfromColoradoinConejosCounty(Spackman
1997+)andfromNewMexicoinTaosandRioArribaCounties(NMRPTC2014).However,within
theseregions,A.ripleyidoesnotoccupyallpotentialhabitatbutratherisrestrictedtovolcanic‐
derivedsubstrates(Ladyman2003).Habitat:Astragalusripleyiexhibitsahighdegreeofhabitat
specificity.Itisapparentlyrestrictedtovolcanicsubstrates,inopen‐canopyponderosapine‐
Arizonafescuesavannah,oralongtheedgesofmixedconiferouswoodland/forestwhereArizona
fescueisdominant.Elevation:InColorado,8200‐9300ft.(Spackmanetal.1997).
EcologicalSystem:PonderosaPineWoodlands
380ColoradoNaturalHeritageProgram©2015
CCVI Scoring
B1)Exposuretosealevelrise.Neutral.
B2a)Distributionrelativetonaturalbarriers.Somewhatincrease.Naturalbarriersborderthe
distributionofthisspeciestotheeast,westandnorthimpairingrangeshift.Astragalusripleyi‘s
rangeisborderedtothewestbythehighpeaksofthenorthwest‐southeasttrendingSanJuan
Mountains,totheeastbythenorth‐southtrendingSangredeCristoMountainRangeandtothe
northbytheeast‐westtrendingLaGaritaMountains.Northwardmigrationthroughthecenterof
therangeisinhibitedbyunsuitablehabitatintheSanLuisvalley(USGS2014).
B2b)Distributionrelativetoanthropogenicbarriers.Somewhatincrease.Conversionof
habitattofarmland(USDA2012)andhabitatalterationbylivestockgrazing(USDOIBLM2014)
impairsrangeshift.
B3)Impactoflandusechangesresultingfromhumanresponsestoclimatechange.Neutral.
Neitherexistingnorplannedrenewableenergydevelopmentwilllikelyimpactthisspecies(NRDC
2011).
C1)Dispersalandmovements.Somewhatincrease.Limitedandlocalizeddispersaldistancein
combinationwithinfrequentseedlingrecruitmentincreasesthisspeciesvulnerabilitytoclimate
changebydecreasingmigrationandestablishmentpotential.Seedsmaybedispersedbysmall
mammals,antsandwindorwater(Ladyman2003).Windcanresultadispersaldistanceof1‐15
meters,smallmammalsandantsupto15metersandwaterdispersaldistanceishighly
unpredictable(VittozandEngler2007)buttypicallynotfartherthan100m(Cainetal.2000).
C2ai)Predictedsensitivitytotemperature:historicthermalniche.Neutral.Consideringthe
meanseasonaltemperaturevariationovertherangeofA.ripleyi,thisspecieshasexperienced
averagetemperaturevariation(57.1‐77oF)overthepast50years(NatureServe2012).
C2aii)Physiologicalthermalniche.Neutral.Thisspeciesisnotdependentoncoolorcold
environments.
C2bi) Predictedsensitivitytochangesinprecipitation,hydrology,ormoistureregime:
historicalhydrologicalniche.Neutral.Consideringtherangeofmeanannualprecipitationacross
occupiedcells,thespecieshasexperiencedaverageprecipitationvariation(21‐40inches)overthe
last50years(NatureServe2012).
C2bii)Predictedsensitivitytochangesinprecipitation,hydrology,ormoistureregime:
physiologicalhydrologicalniche.Increase.PredictedprecipitationdecreasesfromMarchthrough
Juneduringthisspecies’growthandreproductiveseasonarelikelytoreduceestablishmentand
flowering(Ladyman2003)thusimpactabundance,distributionandhabitatquality.
C2c)Dependenceonaspecificdisturbanceregimelikelytobeimpactedbyclimatechange.
Increase.AstragalusripleyioftenoccupiesPonderosa(Pinusponderosa)forests(CNHP2014).
Historically,short‐interval,low‐severitysurfacefiresmaintainedsparse,openstandsinmostdry
ClimateChangeVulnerabilityAssessmentforColoradoBLM381
Ponderosapineforests(Schoennageletal.2004).Consequencesofdecadesoffiresuppressionwith
theaccumulationoffuelsincombinationwithimpactsofrecentclimatechangehavecontributedto
analteredfireregimewithunprecedentedlylarge,high‐severitywildfiresthatarebeyondtherange
ofnaturalvariability(Schoennageletal.2004).
C2d)Dependenceonice,ice‐edge,orsnowcoverhabitats.Neutral.Thisspeciesisnotrestricted
toordependentoniceorsnowcoverhabitats.
C3)Restrictiontouncommongeologicalfeaturesorderivatives.Increase.Astragalusripleyiis
anedaphicendemicthatoccursexclusivelyonvolcanicderivedsoilsassociatedwiththeSanJuan
volcanicfield(NatureServe2014)withacommensuratelylimitedrange.
C4a)Dependenceonotherspeciestogeneratehabitat.Neutral.Astragalusripleyiisnotknown
tobereliantonotherspeciesforhabitatgeneration.
C4c)PollinatorVersatility.Somewhatincrease.Astragalusripleyiappearstobebee‐pollinated.
Beesandantshavebeenobservedonflowersandbumblebees(Bombusternaries)havebeen
reportedasthemostcommonarthropodvisitor(NatureServe2014).
C4d)Dependenceonotherspeciesforpropaguledispersal.Neutral.Littleevidencehasbeen
documentedforanyparticularmethodofdispersal.However,seeddispersalhasbeenspeculatedto
beeffectedbyants,mice,andotherseedstorers,tumblingofdriedplants,andwindorwater
transport(Ladyman2003)andlikelynotdependentonaspecificspecies.
C4e)FormspartofaninterspecificinteractionnotcoveredbyC4a‐d.SomewhatIncrease.A.
rafaelensishasnotbeeninvestigatedfornodulization.However,noduleshavebeenreportedfor
severalotherspeciesinthesubgroupArgophylii(A.crassicarpus,A.missouriensis,A.mollissimus,
andA.purshii),soitispossiblethatA.rafaelensisalsopossessesthisability(DeckerandAnderson
2004).
C5a)Measuredgeneticvariation.Unknown.Nostudieshavebeenundertakentodeterminethe
geneticstructureofeitherrange‐wideorlocalpopulationsalthoughlocallyendemicspeciesof
Astragalustendtoexhibitreducedlevelsofpolymorphismthatmayimplyareducedrobustness
againstenvironmentaluncertainty(Ladyman2003).
C5b)Occurrenceofbottlenecksinrecentevolutionaryhistory.Unknown.
C6)Phenologicalresponsetochangingseasonaltemperatureandprecipitationdynamics.
Unknown.
Literature Cited
ColoradoNaturalHeritageProgram(CNHP).2014.BiodiversityTrackingandConservationSystem(BIOTICS).Colorado
NaturalHeritageProgram,ColoradoStateUniversity,FortCollins.
Cain,M.L.,B.G.Milligan,andA.E.Strand.2000.Long‐distanceSeedDispersalinPlantPopulations.AmericanJournalof
Botany87(9):1217–1227.
382ColoradoNaturalHeritageProgram©2015
Decker,K.andD.G.Anderson.2004.AstragalusanisusM.E.Jones(Gunnisonmilkvetch):atechnicalconservation
assessment.[Online].USDAForestService,RockyMountainRegion.Available:
http://www.fs.fed.us/r2/projects/scp/assessments/astragalusanisus.pdf.[May5,2011].
Ladyman,J.A.R.2003.AstragalusripleyiBarneby(Ripley’smilkvetch):atechnicalconservationassessment.[Online].
USDAForestService,RockyMountainRegion.Available:
http://www.fs.fed.us/r2/projects/scp/assessments/astragalusripley.pdf
Lukas,J.,J.Barsugli,N.Doesken,I.Rangwala,K.Wolter.2014.ClimateChangeinColorado:ASynthesistoSupportWater
ResourcesManagementandAdaptation,SecondEdition.Available
at:http://cwcbweblink.state.co.us/WebLink/ElectronicFile.aspx?docid=191994&searchid=e3c463e8‐569c‐4359‐8ddd‐
ed50e755d3b7&dbid=0
NatureServe2012.ClimateChangeVulnerabilityAssessmentTool,version2.1.Availableonlineat
https://connect.natureserve.org/science/climate‐change/ccvi.
NatureServe.2014.NatureServeExplorer:Anonlineencyclopediaoflife[webapplication].Version7.1.NatureServe,
Arlington,Virginia.Availablehttp://explorer.natureserve.org.(Accessed:November14,2014)
NewMexicoRarePlantTechnicalCouncil(NMRPTC).1999.NewMexicoRarePlants.Albuquerque,NM:NewMexicoRare
PlantsHomePage.http://nmrareplants.unm.edu(Latestupdate:16January2014).
NRDCRenewableEnergyMapNaturalResourcesDefenseCounsel.2011.RenewableenergyforAmerica:harvestingthe
benefitsofhomegrown,renewableenergy.Online.Available:http://www.nrdc.org/energy/renewables/energymap.asp
Accessed2014.
Schoennagel,T.,T.T.Veblen,andW.H.Romme.2004.TheInteractionofFire,Fuels,andClimateacrossRockyMountain
Forests.BioScience,Vol.54No.7,661‐675.
Spackman,S.,B.Jennings,J.Coles,C.Dawson,M.Minton,A.Kratz,andC.Spurrier.1997.ColoradoRarePlantFieldGuide.
PreparedfortheBureauofLandManagement,U.S.FishandWildlifeServiceandU.S.ForestServicebytheColorado
NaturalHeritageProgram,FortCollins.
U.S.DepartmentofAgriculture(USDA).2012.2012CensusofAgriculture.Availableat:
http://www.agcensus.usda.gov/index.php
U.S.DepartmentoftheInterior,BureauofLandManagement(BLM).2014.Availableat:
http://www.geocommunicator.gov/GeoComm/.Accessed2014.
U.S.GeologicalSurvey.2014.TheNationalMap.Availableat:http://nationalmap.gov/viewer.html
VittozP.andEnglerR.2007.Seeddispersaldistances:atypologybasedondispersalmodesandplanttraits.Botanica
Helvetica,117(2),109–124.DOI:10.1007/s00035‐007‐0797‐8

ClimateChangeVulnerabilityAssessmentforColoradoBLM383
Astragalustortipes
SleepingUtemilkvetch
G1/S1
Family:Fabaceae
Climate Vulnerability Rank: Extremely Vulnerable
ThisColoradostate‐widerankisbasedon:1)A.tortipeshasexperiencedaverysmallrangeinmean
annualprecipitationoverthelast50years;2)seeddispersaldistancesareprobablyfairlylimited;
3)barrierstomovement4)shrublandhabitatsoccupiedbyA.tortipesmaybesubjecttoincreased
wildfiresundertheclimatechangeprojectionsofhottertemperatures;5)potentiallackofavailable
soilmoistureunderprojectedclimatewarming;6)potentialsymbioticrelationshipwithroot‐
nodulatingbacteria.
Distribution:Coloradoendemic(UteMountainUteReservation,MontezumaCounty).Estimated
rangeis10squarekilometers(4squaremiles),calculatedinGISbydrawingaminimumconvex
polygonaroundtheknownoccurrences.Habitat:A.tortipesoccursinamixeddesertscrub,
consistingofAtriplexconfertifolia,Chrysothamnusgreenei,andGutierreziasarothrae(Andersonand
Porter1994).Itisendemictogranite‐derivedgravelssouthoftheSleepingUte(ColoradoNational
HeritageProgram1997).Elevationalrange5400‐5700ft(Spackmanetal.1997).Elevation:5450‐
5700feet.
EcologicalSystem:DesertShrub
CCVI Scoring
B1)Exposuretosealevelrise.Neutral.
B2a)Distributionrelativetonaturalbarriers.Increase/SomewhatIncrease.Highmountains
andunsuitablehabitatssurroundmanyoftheA.tortipesoccurrences.
384ColoradoNaturalHeritageProgram©2015
B2b)Distributionrelativetoanthropogenicbarriers.Increase/SomewhatIncrease.Cropland
onthewesternedgeofoccupiedhabitatmayactasabarriertomovementforA.tortipes.
B3)Impactoflandusechangesresultingfromhumanresponsestoclimatechange.Increase.
Shrublandspecieswereranked‘Increase’duetothepotentialofwindandsolardevelopment.
C1)Dispersalandmovements.Increase.Seedsdonotcontainspecializedstructurestoaidin
dispersal,andlikelyfallclosetoparentplant.
C2ai)Predictedsensitivitytotemperature:historicthermalniche.Neutral.Consideringthe
meanseasonaltemperaturevariationforoccupiedcells,A.tortipeshasexperiencedaverage(57.1‐
77°F/31.8‐43.0°C)temperaturevariationinthepast50years.
C2aii)Predictedsensitivitytotemperature:physiologicalthermalniche.Neutral.Thisspecies
isnotlimitedtocoolorcoldenvironments.Itoccursindry,uplandareasdominatedbydesert
shrubs.
C2bi) Predictedsensitivitytochangesinprecipitation,hydrology,ormoistureregime:
historicalhydrologicalniche.GreatlyIncrease.Consideringtherangeofmeanannual
precipitationacrossoccupiedcells,A.tortipeshasexperiencedverysmall(<4inches/100mm)
precipitationvariationinthepast50years.
C2bii)Predictedsensitivitytochangesinprecipitation,hydrology,ormoistureregime:
physiologicalhydrologicalniche.Increase.Climatemodelsprojecthottertemperaturesfor
Colorado,withtrendstowardmoreseveresoil‐moisturedroughtconditionsinColorado(Lukaset
al.2014).Warmertemperatureswillresultinhigherevapotranspirationratesforplants.A.tortipes
occursinasemi‐aridclimatewithanaverageof12.95inchesofprecipitationperyearinnearby
Cortez,CO(WesternRegionalClimateCenter2015).Althoughtolerancelimitsforlackofmoisture
areunknownforthisspecies,ahotterclimatecombinedwithhigherevapotranspirationmayresult
instressfulconditionsforA.tortipes.
C2c)Dependenceonaspecificdisturbanceregimelikelytobeimpactedbyclimatechange.
SomewhatIncrease.A.tortipesoccursinshrublandhabitats.Thesehabitatsmaybemorelikelyto
burnwithincreasedtemperaturesandanincreaseinweedyspeciesthatcomprisetheunderstory,
suchascheatgrass.
C2d)Dependenceonice,ice‐edge,orsnowcoverhabitats.Neutral.Thisspeciesisnotrestricted
toordependentoniceorsnowcoverhabitats.
C3)Restrictiontouncommongeologicalfeaturesorderivatives.Neutral.
C4a)Dependenceonotherspeciestogeneratehabitat.Neutral.Thereisnoevidencethatthis
speciesisdependentonotherspeciestogeneratehabitat.
C4c)PollinatorVersatility.Neutral.AllAstragalusspeciesareranked‘Neutral’basedonUSFS
speciesassessmentsthatindicateseveralwesternAstragalusspeciesarevisitedbyover20species
ofbees(DeckerandAnderson2004).
ClimateChangeVulnerabilityAssessmentforColoradoBLM385
C4d)Dependenceonotherspeciesforpropaguledispersal.Neutral.
C4e)FormspartofaninterspecificinteractionnotcoveredbyC4a‐d.SomewhatIncrease.A.
tortipeshasnotbeeninvestigatedfornodulization.However,noduleshavebeenreportedfor
severalotherspeciesinthesubgroupArgophylii(A.crassicarpus,A.missouriensis,A.mollissimus,
andA.purshii),soitispossiblethatA.tortipesalsopossessesthisability(DeckerandAnderson
2004).
C5a)Measuredgeneticvariation.Unknown.
C5b)Occurrenceofbottlenecksinrecentevolutionaryhistory.Unknown.
C6)Phenologicalresponsetochangingseasonaltemperatureandprecipitationdynamics.
Unknown.
Literature Cited
Anderson,J.L.,andJ.M.Porter.1994.Astragalustortipes(Fabaceae),anewspeciesfromDesertBadlandsinsouthwestern
ColoradoanditsphylogeneticrelationshipswithinAstragalus.SystematicBotany,19(1):116‐125.
ColoradoNaturalHeritageProgram.1997+.ColoradoRarePlantGuide.www.cnhp.colostate.edu.Latestupdate:June30,
2014.
ColoradoNaturalHeritageProgram(CNHP).2014.BiodiversityTrackingandConservationSystem(BIOTICS).Colorado
NaturalHeritageProgram,ColoradoStateUniversity,FortCollins.
Decker,K.andD.G.Anderson.2004.AstragalusanisusM.E.Jones(Gunnisonmilkvetch):atechnicalconservation
assessment.[Online].USDAForestService,RockyMountainRegion.Available:
http://www.fs.fed.us/r2/projects/scp/assessments/astragalusanisus.pdf.[Feb26,2015].
Lukas,J.,J.Barsugli,N.Doesken,I.Rangwala,andK.Wolter2014.ClimateChangeinColorado,ASynthesistoSupport
WaterResourcesManagementandAdaptation,SecondEdition.Availableat:
http://wwa.colorado.edu/climate/co2014report/.Accessed:2014.
Spackman,S.,B.Jennings,J.Coles,C.Dawson,M.Minton,A.Kratz,andC.Spurrier.1997.Coloradorareplantfieldguide.
PreparedforBureauofLandManagement,U.S.ForestServiceandU.S.FishandWildlifeServicebyColoradoNatural
HeritageProgram.
WesternRegionalClimateCenter.2015.AverageannualprecipitationforCortez,Colorado.http://www.wrcc.dri.edu/cgi‐
bin/cliMAIN.pl?co3246.AccessedFeb24,2015.PeriodofRecord:1911to2015.

386ColoradoNaturalHeritageProgram©2015
Bolophytaligulata(Partheniumligulatum)
Coloradofeverfew
G3/S2
Family:Asteraceae
Photo:BobSkowron
Climate Vulnerability Rank: Extremely Vulnerable
ThisColoradostate‐widerankisbasedon:predictedtemperatureincreasesandprecipitation
decreases;presenceofhighmountainrangesandescarpmentsthatpresentnaturalbarriers;
habitatalterationrelatedtooilandgasdevelopmentandlivestockgrazing,whichactas
anthropogenicbarriers;possiblewindpowerdevelopmentonpotentialfuturehabitat;limitedseed
dispersaldistance;restrictiontoarelativelyuncommongeology;andpollinatorlimitations.
Suitablehabitatislikelytobereducedandreproductivesuccessdiminishedasthisspecies’range
becomeswarmeranddrier.Climatemodelsprojectannualnetdryingacrosstherangeofthis
species(NatureServe2012)withresultingtrendstowardmoreseveresoil‐moisturedrought
conditionsinColorado(Lukasetal.2014).
Distribution:BolophytaligulatahasbeenreportedfromColoradoinRioBlancoandMoffat
Counties,andfromUtahinEmeryCounty(NatureServe2014,Welshetal.1987).
EcologicalSystem/Habitat:Bolophytaligulataisknownfrombarrenorsemi‐barrencalciferousor
gypsiferousoutcropsoftheGreenRiver,Uinta,Ferron,Summerville,andCarmelformationsinsalt
desertshrub,serviceberry,rabbitbrush,Indianrice‐grass,greasebush,galleta,blacksagebrush,
pygmysagebrush,andpinyon‐junipercommunities(NatureServe2014).Elevation:1705‐2135
meters(NatureServe2014).
CCVI Scoring
Temperature:CalculatedusingClimateWizard:ensembleaverage,mediumemissionscenario
(A1B),mid‐centurytimeframe,averageannualchange.InColorado,thisspeciesisexpectedtobe
exposedtomeanannualtemperatureincreasesof4.5oFbymid‐century(NatureServe2012).
ClimateChangeVulnerabilityAssessmentforColoradoBLM387
Moisture:CalculatedinGISusingNatureServeHamonAET:PETmoisturemetricdata(thisindex
integratesprojectedtemperatureandprecipitationchangestoindicatehowmuchdryingwilltake
place).InColoradothisspeciesispredictedtobeexposedtonetdryingof9.7to11.9percenton2
percentofitsrange,7.4to9.6percentdryingon13percentofitsrange,5.1to7.3percentdryingon
71percentofitsrangeand2.8to5.0percentdryingon14percentofitsrange.
B1)Exposuretosealevelrise.Neutral.
B2a)Distributionrelativetonaturalbarriers.Somewhatincrease.Severalmountainranges
andescarpments(USGS2014)actasbarrierstoclimatechange‐inducedrangeshiftforthemajority
ofpopulationsofPartheniumligulatum.
B2b)Distributionrelativetoanthropogenicbarriers.Increase.Habitatalterationrelatedto
energyextractionandlivestockgrazingimpairallpopulationsofBolophytaligulatafrom
climatechange–inducedrangeshift.Allpopulationsoccurinornearshaleplaysandbasinsandare
surroundingbyactiveoilandgasdevelopment(FracFocusWells2013).Additionally,themajority
ofthishabitatinspeciesrangeispubliclandmanagedbytheBLMasrangelandforlivestock(BLM
2014).
B3)Impactoflandusechangesresultingfromhumanresponsestoclimatechange.
Somewhatincrease.ExistingandplannedwindpowerdevelopmentontheUtah‐Wyomingborder
(NRDC2011)mayalterhabitatonthepotentialfuturerangeofBolophytaligulata.Because
Bolophytaligulataismoderatelyvulnerabletohabitatalteration(Rocchio2007),windpower‐
relateddevelopmentmaynegativelyimpactthisspeciessurvivability.
*Bolophytaligulata’slifehistorystrategiescanbesuggestedbyBolophytaalpina(Parthenium
alpinum)strategies.BolophytaligulataisverycloselyrelatedtoP.alpinum,suchthattheoriginal
taxonomicrankofP.ligulatumwasavarietyofP.alpinumthatwaslaterelevatedtospecieslevel
(HeidelandHandley2004).
C1)Dispersalandmovements.Somewhatincrease.Windisthelikelydispersalagentfor
Bolophytaalpina(Partheniumalpinum),andthusforB.ligulata.AchenesofB.alpinahavefringed,
wing‐likemembranousextensionsofthepappuswhichcanimprovedispersaldistanceupto15
meters(VittozandEngler2007).
C2ai)Predictedsensitivitytotemperature:historicthermalniche. Neutral. Consideringthe
meanseasonaltemperaturevariationforoccupiedcells,thespecieshasexperiencedaverage
temperaturevariation(57.1‐77oF)inthepast50years(NatureServe2012).
C2aii)Predictedsensitivitytotemperature:physiologicalthermalniche.Somewhatincrease.
Bolophytaligulatamayrequirecoldtemperaturestoinduceflowering.Winterandspring
temperaturesarepredictedtowarmby4.6oFto4.7oF(NatureServe2012)andthusmaybe
inadequatetopromotefloweringorconverselymayprovidemiscuesthatalterflowering
phenology.Timingoflifehistorytraitsiscentraltolifetimefitnessandnowhereisthismore
importantasinthephenologyoffloweringingoverningplantreproductivesuccess(Inouye2008).
388ColoradoNaturalHeritageProgram©2015
C2bi) Predictedsensitivitytochangesinprecipitation,hydrology,ormoistureregime:
historicalhydrologicalniche.Somewhatincrease.Consideringtherangeofmeanannual
precipitationacrossoccupiedcells,thespecieshasexperiencedsmall(10.1inches)precipitation
variationinthepast50years(NatureServe2014).
C2bii)Predictedsensitivitytochangesinprecipitation,hydrology,ormoistureregime:
physiologicalhydrologicalniche.Somewhatincrease.AlthoughBolophytaligulataiswell
adaptedtoenvironmentalextremes,predictedprecipitationdecreasesduringtheperiodof
floweringandfruitingmaydiminishreproductivesuccess.
C2c)Dependenceonaspecificdisturbanceregimelikelytobeimpactedbyclimatechange.
Unknown.InColorado,Bolophytaligulatatypicallyoccupiessparselyvegetatedsitesthatdonot
carryfirewell.Although,thesesitesarealsotypicallysurroundedbycommunitiessuchassage
shrublandsandpinyon‐juniperwoodlandswherefirefrequenciesareexpectedtoincreaseinthe
future,followingtrendsthatalreadyshowincreasedfirefrequencies,areaburnedandfireseverity
(Stephens2005,Westerlingetal.2006,Littelletal.2009.However,asyet,impactsonB.ligulata
hasnotbeendocumented.
C2d)Dependenceonice,ice‐edge,orsnowcoverhabitats.Neutral.Thisspeciesisnot
restrictedtoordependentoniceorsnowcoverhabitats.
C3)Restrictiontouncommongeologicalfeaturesorderivatives.Increase.Bolophytaligulatais
edaphicallyrestrictedtocalciferousorgypsiferousoutcropsofshalesandclaysoftheGreenRiver,
Uinta,Ferron,andCarmelformations(Welshetal.1987).
C4a)Dependenceonotherspeciestogeneratehabitat.Neutral.Bolophytaligulatahasnotbeen
showntobedependentonotherspeciestogeneratehabitat.
C4c)PollinatorVersatility.Somewhatincrease.PollinationofthecloselyrelatedB.alpinamay
requirespecializedpollinationvectors,suggestingsimilarpollinationrequirementsforB.ligulata.
C4d)Dependenceonotherspeciesforpropaguledispersal.Neutral.
C4e)FormspartofaninterspecificinteractionnotcoveredbyC4a‐d.Unknown.
C5a)Measuredgeneticvariation.Unknown.
C5b)Occurrenceofbottlenecksinrecentevolutionaryhistory.Unknown.
C6)Phenologicalresponsetochangingseasonaltemperatureandprecipitationdynamics.
Unknown.
Literature Cited
ColoradoNaturalHeritageProgram(CNHP).2014.BiodiversityTrackingandConservationSystem(BIOTICS).Colorado
NaturalHeritageProgram,ColoradoStateUniversity,FortCollins.
ClimateChangeVulnerabilityAssessmentforColoradoBLM389
FracFocusWells.2013.MapProvidedbyFracTrackerAllianceonFracTracker.org.Availableat:
http://www.fractracker.org/map/national/
Heidel,B.andJ.Handley.2004.Partheniumalpinum(Nutt.)Torr.&Gray(alpinefeverfew):atechnicalconservation
assessment.[Online].USDAForestService,RockyMountainRegion.
Available:http://www.fs.fed.us/r2/projects/scp/assessments/partheniumalpinum.pdf.Accessed:2014.
Inouye,D.W.2008.Effectsofclimatechangeonphenology,frostdamage,andfloralabundanceofmontanewildflowers.
Ecology89:353–362.http://dx.doi.org/10.1890/06‐2128.1
Littell,J.,D.McKenzie,D.Peterson,andA.Westerling.2009.ClimateandwildfireareaburnedinwesternU.S.
ecoprovinces,1916‐2003.EcologicalApplications19:1003‐1021
Lukas,J.,J.Barsugli,N.Doesken,I.Rangwala,andK.Wolter2014.ClimateChangeinColorado,ASynthesistoSupport
WaterResourcesManagementandAdaptation,SecondEdition.Availableat:
http://wwa.colorado.edu/climate/co2014report/.Accessed:2014.
NatureServe2012.ClimateChangeVulnerabilityAssessmentTool,version2.1.Availableonlineat
https://connect.natureserve.org/science/climate‐change/ccvi.
NatureServe.2014.NatureServeExplorer:Anonlineencyclopediaoflife[webapplication].Version7.1.NatureServe,
Arlington,Virginia.Availablehttp://explorer.natureserve.org.Accessed2014.
NRDCRenewableEnergyMapNaturalResourcesDefenseCounsel.2011.RenewableenergyforAmerica:harvestingthe
benefitsofhomegrown,renewableenergy.Online.Available:http://www.nrdc.org/energy/renewables/energymap.asp
(accessed2014).
Rocchio,J.2007.FloristicQualityAssessmentIndicesforColoradoPlantCommunities.ColoradoNaturalHeritage
Program,ColoradoStateUniversity,FortCollins,CO.
Spackman,S.,B.Jennings,J.Coles,C.Dawson,M.Minton,A.Kratz,andC.Spurrier.1997.ColoradoRarePlantFieldGuide.
PreparedfortheBureauofLandManagement,U.S.FishandWildlifeServiceandU.S.ForestServicebytheColorado
NaturalHeritageProgram,FortCollins.
Stephens,S.L.2005.ForestfirecausesandextentonUnitedStatesForestServicelands.InternationalJournalofWildland
Fire14:213‐222.
U.S.GeologicalSurvey(USGS).2014.TheNationalMap.Availableat:http://nationalmap.gov/viewer.html.Accessed2014.
VittozP.andEnglerR.2007.Seeddispersaldistances:atypologybasedondispersalmodesandplanttraits.Bot.Helv.
117:109–124.
Welsh,S.L.,N.D.Atwood,andJ.C.Higgins.1987.GreatBasinNaturalistMemoir,no.9.BrighamYoungUniversity,ISBN0‐
8425‐2260‐3.
Westerling,A.L.,B.P.Bryant,H.K.Preisler,T.P.Holmes,H.G.Hidalgo,T.Das,andS.R.Shrestha.2011.Climatechangeand
growthscenariosforCaliforniawildfire.ClimaticChange109:445‐463.

390ColoradoNaturalHeritageProgram©2015
Camissoniaeastwoodiae
Eastwoodeveningprimrose
G2/S1
Family:Onagraceae
Photo:JanisHuggins
Climate Vulnerability Rank: Highly Vulnerable
ThisColoradostate‐widerankisbasedonthefollowingfactors:1)C.eastwoodiaehasexperiencea
smallrangeinprecipitationinthelast50years;2)availablesoilmoisturemaydecreaseif
temperaturesincreaseaspredictedinclimatemodels;3)potentialforincreasedenergy
developmentwithinsuitablehabitat;4)likelihoodofshortseeddispersaldistance;5)potentialfor
increasedfirefrequencyinpinyon‐juniperandshrublandhabitatthatsupportC.eastwoodiae
populations.
Distribution:EndemictotheColoradoPlateau.FoundinUtah(sevencounties),Arizona(2
counties),andColorado(2counties,USDANRCS2012).Habitat:InColoradothisspeciesisfound
onclaysoilsderivedfromMancosshalewithAtriplexgardneriadominantassociate.Elevation:
4,570‐6,050feet.
EcologicalSystem:SaltbushFlatsandFans,Pinyon‐Juniper
CCVI Scoring
B1)Exposuretosealevelrise.Neutral.
B2a)Distributionrelativetonaturalbarriers.Neutral.
B2b)Distributionrelativetoanthropogenicbarriers.Neutral.
B3)Impactoflandusechangesresultingfromhumanresponsestoclimatechange.Increase.
AreasofC.eastwoodiaehabitatmayhavepotentialforincreasedoilandgas,aswellaswindand
solardevelopment.
ClimateChangeVulnerabilityAssessmentforColoradoBLM391
C1)Dispersalandmovements.Increase.Seedslikelyfallclosetoparentplant.
C2ai)Predictedsensitivitytotemperature:historicthermalniche.SomewhatDecrease.
Consideringthemeanseasonaltemperaturevariationforoccupiedcells,thespecieshas
experiencedgreaterthanaverage(>77°F/43.0°C)temperaturevariationinthepast50years.
C2aii)Predictedsensitivitytotemperature:physiologicalthermalniche.Neutral.Thisspecies
isnotlimitedtocoolorcoldhabitatsthatareexpectedtobelosttoclimatechange.
C2bi) Predictedsensitivitytochangesinprecipitation,hydrology,ormoistureregime:
historicalhydrologicalniche.Increase.Consideringtherangeofmeanannualprecipitationacross
occupiedcells,thespecieshasexperiencedsmall(4‐10inches/100‐254mm)precipitation
variationinthepast50years.
C2bii)Predictedsensitivitytochangesinprecipitation,hydrology,ormoistureregime:
physiologicalhydrologicalniche.SomewhatIncrease.Climatemodelsprojecthotter
temperaturesforColorado,withtrendstowardmoreseveresoil‐moisturedroughtconditionsin
Colorado(Lukasetal.2014).Warmertemperatureswillresultinhigherevapotranspirationrates
forplants.C.eastwoodiaeoccursinasemi‐aridclimatewithanaverageof11.33inchesof
precipitationperyearinnearbyGrandJunction,CO(WesternRegionalClimateCenter2015).
Althoughtolerancelimitsforlackofmoistureareunknownforthisspecies,ahotterclimate
combinedwithhigherevapotranspirationmayresultinstressfulconditionsforC.eastwoodiae.
C2c)Dependenceonaspecificdisturbanceregimelikelytobeimpactedbyclimatechange.
SomewhatIncrease.Increasedfirefrequencymayoccurinshrublandsandpinyon‐juniper
ecosystemsthatsupportpopulationsofC.eastwoodiae.
C2d)Dependenceonice,ice‐edge,orsnowcoverhabitats.Neutral.Thisspeciesisnotrestricted
toordependentoniceorsnowcoverhabitats.
C3)Restrictiontouncommongeologicalfeaturesorderivatives.Neutral.
C4a)Dependenceonotherspeciestogeneratehabitat.Neutral.Thereisnoevidencethatthis
speciesisdependentonotherspeciestogeneratehabitat.
C4c)PollinatorVersatility.Unknown.
C4d)Dependenceonotherspeciesforpropaguledispersal.Neutral.
C4e)FormspartofaninterspecificinteractionnotcoveredbyC4a‐d.Unknown.
C5a)Measuredgeneticvariation.Unknown.
C5b)Occurrenceofbottlenecksinrecentevolutionaryhistory.Unknown.
C6)Phenologicalresponsetochangingseasonaltemperatureandprecipitationdynamics.
Unknown.
392ColoradoNaturalHeritageProgram©2015
Literature Cited
ColoradoNaturalHeritageProgram.1997+.ColoradoRarePlantGuide.www.cnhp.colostate.edu.Latestupdate:June30,
2014.
ColoradoNaturalHeritageProgram(CNHP).2014.BiodiversityTrackingandConservationSystem(BIOTICS).Colorado
NaturalHeritageProgram,ColoradoStateUniversity,FortCollins.
FracFocusWells.2013.MapProvidedbyFracTrackerAllianceonFracTracker.org.Availableat:
http://www.fractracker.org/map/national/
Littell,J.,D.McKenzie,D.Peterson,andA.Westerling.2009.ClimateandwildfireareaburnedinwesternU.S.
ecoprovinces,1916‐2003.EcologicalApplications19:1003‐1021
Lukas,J.,J.Barsugli,N.Doesken,I.Rangwala,andK.Wolter2014.ClimateChangeinColorado,ASynthesistoSupport
WaterResourcesManagementandAdaptation,SecondEdition.Availableat:
http://wwa.colorado.edu/climate/co2014report/.Accessed:2014.
USDA,NRCS.2012.ThePLANTSDatabase.NationalPlantDataTeam,Greensboro,NC27401‐4901USA.
WesternRegionalClimateCenter.2015.AverageannualprecipitationforGrandJunction,Colorado.
http://www.wrcc.dri.edu/cgi‐bin/cliMAIN.pl?co3488.AccessedFeb24,2015.PeriodofRecord:1900to2015.

ClimateChangeVulnerabilityAssessmentforColoradoBLM393
Cleome(Peristome)multicaulis
Slenderspiderflower
G2G3/S2S3
Family:Capparaceae
Photo:GeorgiaDoyle
Climate Vulnerability Rank: Extremely Vulnerable
ThisColoradostate‐widerankisbasedonthefollowingfactors:1)barrierstomovement;2)
potentialforsolarandwinddevelopmentinSanLuisValley;3)likelihoodoflimitedseeddispersal;
4)specieshasexperienceverysmallprecipitationvariationinlast50years;4)restrictionto
alkalineorsalinesoilsinwetlands.
Distribution:Mexico,Texas,Arizona,NewMexico,Wyoming,andColorado(USDANRCS2013).
WeberandWittmann(2012)reportthatthisspeciesiswidelydistributedinMexico.Habitat:
Cleomemulticaulisisrestrictedtosalineoralkalinesoils,aroundalkalisinks,ponds,alkaline
meadows,oroldlakebeds.Thesurroundingplantcommunityissalinebottomlandshrubland
(dominatedbySarcobatusandChrysothamnus).Theplantoftengrowsinbandsjustaboverushes
(Juncussp.)andmayextendintogreasewoodandsaltgrass(Graff1992,Spackmanetal.1997,
ColoradoNaturalHeritageProgram2014).Elevation:7,500‐8,200feet.
EcologicalSystem:Grass/ForbDominatedWetlands;Playas
CCVI Scoring
B1)Exposuretosealevelrise.Neutral.
B2a)Distributionrelativetonaturalbarriers.Greatlyincrease.Knownoccurrencesarelimited
totheflooroftheSanLuisValley,andsurroundinghighmountainsmayactasabarriersto
movement.
B2b)Distributionrelativetoanthropogenicbarriers.Neutral.
394ColoradoNaturalHeritageProgram©2015
B3)Impactoflandusechangesresultingfromhumanresponsestoclimatechange.Increase.
AnincreaseinsolarandwinddevelopmentcouldoccurintheSanLuisValley.
C1)Dispersalandmovements.Increase.Noinformationisavailableondispersal,butseedslikely
fallclosetoparentplants.
C2ai)Predictedsensitivitytotemperature:historicthermalniche.SomewhatDecrease.
Consideringthemeanseasonaltemperaturevariationforoccupiedcells,thespecieshas
experiencedgreaterthanaverage(>77°F/43.0°C)temperaturevariationinthepast50years.
C2aii)Predictedsensitivitytotemperature:physiologicalthermalniche.Neutral.Thisspecies
isnotlimitedtocoolorcoldhabitatsthatarelikelytobelosttoclimatechange.
C2bi) Predictedsensitivitytochangesinprecipitation,hydrology,ormoistureregime:
historicalhydrologicalniche.GreatlyIncrease.Consideringtherangeofmeanannual
precipitationacrossoccupiedcells,thespecieshasexperiencedverysmall(<4inches/100mm)
precipitationvariationinthepast50years.
C2bii)Predictedsensitivitytochangesinprecipitation,hydrology,ormoistureregime:
physiologicalhydrologicalniche.GreatlyIncrease.Cleomemulticaulisisrestrictedtosalineor
alkalinesoils,aroundalkalisinks,ponds,alkalinemeadows,oroldlakebeds.Thesewetlandsites
occurinthearidclimateSanLuisValley,whereaverageannualprecipitationis9.39inchesinDel
Norte,CO(WesternRegionalClimateCenter2015).
C2c)Dependenceonaspecificdisturbanceregimelikelytobeimpactedbyclimatechange.
Neutral.
C2d)Dependenceonice,ice‐edge,orsnowcoverhabitats.Neutral.Thisspeciesisnotrestricted
toordependentoniceorsnowcoverhabitats.
C3)Restrictiontouncommongeologicalfeaturesorderivatives.Neutral.
C4a)Dependenceonotherspeciestogeneratehabitat.Neutral.Thereisnoevidencethatthis
speciesisdependentonotherspeciestogeneratehabitat.
C4c)PollinatorVersatility.Unknown.
C4d)Dependenceonotherspeciesforpropaguledispersal.Neutral.