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Conservation triage at the trailing edge of climate envelopes

DOI:10.1111/cobi.13401
Authors:
Sophie Louise Gilbert at University of Idaho
Sophie Louise Gilbert
Kate Broadley at Fuse Consulting Ltd.
Kate Broadley
  • Fuse Consulting Ltd.
Darcy Doran-Myers at University of Florida
Darcy Doran-Myers
Amanda Droghini at University of Alaska Anchorage
Amanda Droghini
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Abstract

Article impact statement: Resources should target leading edges of species’ climate envelopes rather than populations at the trailing edge of climate change. This article is protected by copyright. All rights reserved
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Diversity
Conservation triage at the trailing edge of climate
envelopes
Sophie L. Gilbert ,1Kate Broadley,2Darcy Doran-Myers,2Amanda Droghini,2
Jessica A. Haines ,2Anni H¨
am¨
al¨
ainen,3Clayton T. Lamb,2Eric W. Neilson,2and Stan Boutin2
1Department of Fish & Wildlife Sciences, University of Idaho, Moscow, ID, 83844, U.S.A., email sophiegilbert@uidaho.edu
2Department of Biological Sciences, University of Alberta, Edmonton, AB, T6G0C5, Canada
3School of Optometry, Universit´
edeMontr
´
eal, Montr´
eal, QC CAN, H3T1P1, Canada
Introduction
Species protection via geographically fixed conservation
actions is a primary tool for maintenance of biodiversity
worldwide (Pimm et al. 2014). Yet, for many species,
the assumption that currently suitable sites will remain
so is undermined by climate change (Urban 2015; Wiens
2016). Climate-change-associated range shifts (Chen et al.
2011), a process driven by populations at the trailing
edge of the climate envelope going extinct or moving and
those at the leading edge becoming established, are be-
coming widespread around the world (Wiens 2016). We
argue that conservation of populations of at-risk species
should be prioritized across each species’ range based on
future climatic suitability of an area with the goal of main-
taining or increasing the number of viable populations
range wide. Such range-wide prioritization could help
conserve species in a changing climate when resources
are limited; effort would be reallocated to viable popu-
lations (Oliver et al. 2012; Alagador & Cerdeira 2016).
Promisingly, resistance to this approach (Oliver et al.
2016) may be waning. Many nongovernment organiza-
tions (e.g., International Panel on Climate Change, World
Wildlife Fund) now use climate-informed range-wide ap-
proaches, as do some national and state agencies (e.g.,
Association of Fish & Wildlife Agencies 2018; Cornwall
2018). We aimed to advance discussion and implemen-
tation of climate-informed prioritization across species’
ranges and considered when populations behind the trail-
ing edge of climate change should be deprioritized.
Article impact statement: Resources should target leading edges of species’ climate envelopes rather than populations at the trailing edge of
climate change.
Paper submitted November 25, 2017; revised manuscript accepted June 22, 2019.
An Urgently Needed Approach
Deprioritizing populations that are no longer viable under
climate change is critical but remains rarely discussed.
Most decision tools and conservation plans focus on en-
hancements within and on the leading edge of climate
envelopes (connectivity, habitat improvement, refugia
protection, and assisted migration [Jones et al. 2016]),
whereas decisions for trailing-edge populations are rarely
discussed. As climate conditions worsen at the trailing
edge, affected populations will near extinction despite
conservation actions (e.g., threat mitigation, protection
of habitat). Nevertheless, species-specific, geographically
static conservation actions are status quo and common.
One-fifth of protected areas worldwide aim to protect
specific species (IUCN 2008; Supporting Information).
For example, protection and restoration designed to stop
declines of woodland caribou (Rangifer tarandus cari-
bou) do not consider that these populations may already
be outside their climate envelope (Murray et al. 2015);
likewise, sea-level rise will eventually drive Florida key
deer (Odocoileus virginianus clavium) to extinction,
yet in situ conservation actions continue (Maschinski
et al. 2011).
Principles of conservation prioritization could be used
to reallocate resources from climate-change unviable
to climate-change viable populations within each at-
risk species’ shifting climate envelopes, which we term
trailing-edge triage. Unlike multispecies conservation
triage, in which resources are reallocated among species
1
Conservation Biology,Volume0,No.0,1–4
C
2019 Society for Conservation Biology
DOI: 10.1111/cobi.13401
2Conservation Triage
!"#
N
Climate is driving decline of
a trailing-edge population?
Continue in situ
conservation
N
BACD
Pole
Population still present?
N
Re-allocate actions
within the climate
envelope
Is remaining population
critically important?
Reallocate actions
within the climate
envelope
N
Is there viable habitat within
the climate envelope?
Relocate population
within climate
envelope
Y
Intensive management
intervention in situ
N
YYY
(a) (b) (c) (d) (e)
Reallocate actions
within the climate
envelope
Figure 1. Conceptual diagram of 4 primary scenarios (rectangles) and actions (ovals) resulting from the
difference between a protected-area (PA) designated for a population of a target species (solid-line polygon) and
the PA designed to encompass the species’ climate envelope (dashed-line polygon). Shown as an example are a
population of woodland caribou and their northward-shifting climate envelope. Scenarios are (a) no range shift;
(b) population shifts range, leaving unoccupied, but protected habitat; (c) population does not shift range, but is
not essential for species persistence; (d) protected population does not shift range, is essential, and viable habitat
exists elsewhere; and (e) protected population does not shift range, is critical, and no habitat exists elsewhere.
(Hobbs & Kristjanson 2003; Bottrill et al. 2008; Gerber
2016), trailing-edge triage allocates resources within the
range of a target species toward populations likely to
remain viable under future climate change and away from
those at the trailing edge, where efforts are least likely to
be effective (Oliver et al. 2012; Alagador et al. 2014). Such
an approach should maximize the preservation of biodi-
versity with limited resources in a changing climate. Four
primary scenarios could occur for populations behind the
trailing edge (Fig. 1). These scenarios and potential triage
actions do not encompass all the social, economic, and
political complexities inherent in conservation decision
making (Wintle et al. 2011; Hagerman & Satterfield 2014),
which are beyond the scope of this article but are critical
to resolve if trailing-edge triage is to succeed in the long
term (Sinclair et al. 2018). Further, our arguments also
apply to species assemblages of conservation concern
(e.g., coral reefs, short-grass prairie).
Reprioritization
Determining which populations to deprioritize requires
species-specific, range-wide analysis of climate vulner-
ability to identify climate-change unviable and viable
populations so that resources can be reallocated. Range-
wide vulnerability analysis currently encompasses several
approaches (e.g., correlative, mechanistic, or trait-based
[Pacifici 2015]), and recent advances show promise for
integrating these approaches (Razgour et al. 2018). The
potential for in situ evolutionary adaptation to climate
change should simultaneously be facilitated and thresh-
olds for decline agreed on by decision makers prior to
prioritization (Doak & Morris 2010; Boutin & Lane 2014).
Careful analysis and decision making should be used to
disentangle interactive effects, reduce attribution uncer-
tainty, and make robust, adaptive decisions (Oliver &
Morecroft 2014).
Several frameworks exist that can inform decisions
about how to address climate-change unviable popula-
tions. They offer practical, detailed guidance (e.g., Oliver
et al. 2012; Alagador & Cerdeira 2016); therefore, we
only highlight the general process (Fig. 1). First, if a
population shifts range to keep pace with its climate
envelope, then what remains behind the trailing edge
is a remnant population and potentially a relict, species-
specific protected or management area (Fig. 1b). In this
situation, conservation actions, including continued habi-
tat protection, would likely cease (but not in multispecies
protected areas such as national parks) (Schneider et al.
2010; Alagador et al. 2014).
If a population cannot track the climate envelope and is
not critical to the persistence of the species (Fig. 1c), then
active management of that population would likewise
cease, although considerations such as maintenance of
genetic diversity must be taken into account. In contrast,
populations unable to follow their moving climate enve-
lope but deemed critical and with viable habitat (i.e.,
areas with suitable environmental and socioeconomic
conditions [Schneider et al. 2010; Corlett 2016]) else-
where (Fig. 1d) would require ex situ management, such
as assisted migration or captive breeding (Dawson et al.
2011). Finally, some populations deemed critical to the
persistence of a species would become stranded outside
Conservation Biology
Volume 0, No. 0, 2019
Gilbert et al. 3
their climate envelopes and would lack viable habitat
elsewhere (Fig. 1e). In this case, drastic and ongoing
interventions would be required (e.g., maintenance of
a conservation-reliant population [Shoo et al. 2013]).
Seizing the Opportunity
Unless geographically static conservation policies are
adapted to include trailing-edge triage, increasing con-
servation failures and economic costs are likely as popu-
lations fall behind the trailing edge of climate envelopes
and the cost of conserving them escalates. Yet, depriori-
tizing trailing-edge populations that are no longer climate-
change viable is so far a rarely adopted strategy.
We see a number of barriers to adoption, foremost
among which may be trepidation and loss aversion within
the conservation community. We acknowledge that triag-
ing trailing-edge populations is unsettling and therefore
suggest that further research into understanding and mit-
igating resistance to prioritization and triage is key to
further progress. There is a growing recognition of the
joint need to both increase and better allocate total con-
servation resources within the conservation community
(Hagerman & Satterfield 2014), which has sparked a sub-
sequent resurgence in discussions of conservation triage
(Cornwall 2018). Yet, some level of uncertainty will al-
ways remain when determining whether a population is
climate-change unviable, which points to the need for
involvement of social scientists (e.g., decision science,
behavioral economics, etc.) in the conservation prioriti-
zation process. Further, we see the evaluation of these
populations and their responses to climate change as
an ongoing process to be incorporated into an adaptive-
management framework. Regular monitoring and adap-
tive management will increase the chance of success.
Another key challenge to adoption of trailing-edge
triage is the multijurisdictional nature of prioritization
decisions. Inevitably, some target species will shift range
across intra- and international boundaries, challenging
resource-reallocation efforts, although existing multina-
tional agreements could be adapted or serve as a produc-
tive starting point (e.g., The Migratory Bird Treaty Act,
UN Convention on Migratory Species, Convention on Bi-
ological Diversity, and the Convention on International
Trade in Endangered Species).
Adoption of trailing-edge triage is urgent. Range shifts
are occurring faster than anticipated (Chen et al. 2011),
and protective policies that are spatially static could
erode public support due to real or perceived conser-
vation failure behind the trailing edge (Tam & McDaniels
2013). As the no-analog climate future unfolds, novel
tools such as trailing-edge triage could increase conserva-
tion success for at-risk species and provide a mechanism
for funding conservation efforts elsewhere in species’
ranges. Given the increasing interest in climate-informed
prioritization and the escalating costs of continued in-
vestment in trailing-edge populations, we suggest that
now is the time for rapid investment into all aspects of
trailing-edge triage and subsequent widespread adoption.
Acknowledgments
We thank, R. Serrouya, C. DeMars, M. Dickie, M. Peers, Y.
Majchrzak, and R. Schneider for productive discussions
of these ideas.
Supporting Information
Calculations regarding species-specific protected areas
(Appendix S1) are available online. The authors are solely
responsible for the content and functionality of these
materials. Queries (other than absence of the material)
should be directed to the corresponding author.
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Supplementary resource (1)

Gilbert et al 2019 Trailing Edge Triage.pdf
Data
August 2019
Sophie Louise Gilbert · Kate Broadley · Darcy Doran-Myers · Amanda Droghini · Stan A Boutin
... Given widespread threats and limited conservation funding, threatened species managers often need to prioritise management interventions across multiple locations (Pritchard et al., 2022;Thomson et al., 2020). Although widely used, conservation prioritisation can be contentious when managers are faced with decisions to deprioritise some locations, potentially accepting declines in populations in these locations to improve overall outcomes for a species (Gilbert et al., 2020). Without substantial increases in conservation funding, such decisions are likely to become commonplace as the effects of climate and land-use change intensify and previously suitable locations for a species become unsuitable (Cornwall, 2018). ...
... Without substantial increases in conservation funding, such decisions are likely to become commonplace as the effects of climate and land-use change intensify and previously suitable locations for a species become unsuitable (Cornwall, 2018). For example, predicted increases in the frequency and intensity of drought across many parts of the world may necessitate decisions to establish new populations in locations with persistent surface-or ground-water while deprioritising those in the most drought-affected locations (Gilbert et al., 2020). Decisions about where and how to manage threatened species should be informed by the likely long-term outcomes for individual populations as well as the species as a whole, accounting for potential future climates and land uses. ...
... Without additional resources, the prioritisation of some populations (or locations) at the expense of others is likely to become commonplace as threats to biodiversity escalate (Cornwall, 2018;Gilbert et al., 2020). Where resources are limited, prioritisation may require conservation managers to emphasise the locations least exposed to future risk and allocate fewer resources to those most at risk (Gilbert et al., 2020). ...
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There is an urgent need to quantify the potential for conservation interventions to effectively manage the impacts of climate change on species' populations and ecological communities. In this first quantitative global assessment of biodiversity conservation interventions for climate change adaptation, we identified 77 peer-reviewed studies, including 443 cases describing the response of individual species' populations or assemblages to particular interventions, whilst also accounting for responses to climate change or particular climatic variables. Eighty-two percent of studies were from Europe or North America. In 30% of reported cases, interventions were regarded as beneficial (having a significant positive impact on a population also affected by a climatic variable). However, beneficial outcomes were more likely to be reported when fewer responses were analysed, suggesting a publication bias in the reporting of beneficial responses. Management focused on particular species (e.g. targeted habitat management and species recovery interventions) was modelled to have a higher probability (73%) of being beneficial than more generic interventions such as land and water management (22%) or protection (17%). Although more data on the effectiveness of climate change adaptation for species conservation are required, the diversity of examples reviewed suggests that climate change adaptation can successfully reduce negative impacts of, or enhance positive responses to, climate change. Targeted interventions maximise the persistence of the most vulnerable populations, whilst expanding habitat management and site protection interventions may benefit the largest number of species and ecosystems. The effective monitoring and evaluation of adaptation interventions is required to improve this evidence-base for future decision-making.
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... As a result of steep population declines, and conflicting political and societal priorities between land stewardship and resource extraction, wildlife managers have shifted their focus from working solely on longer-term strategies of protecting habitat to shorter-term efforts (Nagy-reis et al. 2021). These short-term efforts focus on caribou predators and competitors (i.e., wolf removal or increased deer and moose hunting) (Hervieux et al. 2014;Serrouya et al. 2019), protecting neonate calves via maternal penning (Serrouya et al. 2019), with growing calls for, and concerns of, conservation triage in some cases (Schneider et al. 2010;Vucetich, Nelson & Bruskotter 2017;Cornwall 2018;Gilbert et al. 2020). ...
Indigenous-led conservation: Pathways to recovery for the nearly extirpated Klinse-Za mountain caribou
Article
Full-text available
  • Mar 2022
Indigenous Peoples around the northern hemisphere have long relied on caribou for subsistence, ceremonial, and community purposes. Unfortunately, despite recovery efforts by Federal and Provincial agencies, caribou are currently in decline in many areas across Canada. In response to recent and dramatic declines of mountain caribou populations within their traditional territory, West Moberly First Nations and Saulteau First Nations (collectively, the 'Nations') came together to create a new vision for caribou recovery on the lands they have long stewarded and shared. The Nations focused on the Klinse-Za subpopulation, which had once encompassed so many caribou that West Moberly Elders remarked that they were "like bugs on the landscape". The Klinse-Za caribou declined from ~250 in the 1990's to only 38 in 2013, rendering Indigenous harvest of caribou non-viable and infringing on treaty rights to a subsistence livelihood. In collaboration with many groups and governments, this Indigenous-led conservation initiative paired short-term population recovery actions-predator reduction and maternal penning-with long-term habitat protection in an effort to create a self-sustaining caribou population. Here, we review these recovery actions and the promising evidence that the abundance of Klinse-Za caribou has more than doubled from 38 animals in 2013 to 101 in 2021, representing rapid population growth in response to recovery actions. With looming extirpation averted, the Nations focused efforts on securing a landmark conservation agreement in 2020 that protects caribou habitat over a 7,986 km2 area. The Agreement provides habitat protection for >85% of the Klinse-Za subpopulation (up from only 1.8% protected pre-conservation agreement) and affords moderate protection for neighboring caribou subpopulations (29-47% of subpopulation areas, up from 0-20%). This Indigenous-led conservation initiative has set both the Indigenous and Canadian governments on the path to recover the Klinse-Za subpopulation and reinstate a culturally meaningful caribou hunt. This effort highlights how Indigenous governance and leadership can be the catalyst needed to establish meaningful conservation actions, enhance endangered species recovery, and honor cultural connections to now imperilled wildlife.
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Organismal effects of heat in a fixed ecological niche: Implications on the role of behavioral buffering in our changing world
Article
Increasingly frequent and intense heatwaves generate new challenges for many organisms. Our understanding of the ecological predictors of thermal vulnerability is improving, yet, at least in endotherms, we are still only beginning to understand one critical component of predicting resilience: exactly how do wild animals cope with sub-lethal heat? In wild endotherms, most prior work focuses on one or a few traits, leaving uncertainty about organismal consequences of heatwaves. Here, we experimentally generated a 2.8 °C heatwave for free-living nestling tree swallows (Tachycineta bicolor). Over a week-long period coinciding with the peak of post-natal growth, we quantified a suite of traits to test the hypotheses that (a) behavioral or (b) physiological responses may be sufficient for coping with inescapable heat. Heat-exposed nestlings increased panting and decreased huddling, but treatment effects on panting dissipated over time, even though heat-induced temperatures remained elevated. Physiologically, we found no effects of heat on: gene expression of three heat shock proteins in blood, muscle, and three brain regions; secretion of circulating corticosterone at baseline or in response to handling; and telomere length. Moreover, heat had a positive effect on growth and a marginal, but not significant, positive effect on subsequent recruitment. These results suggest that nestlings were generally buffered from deleterious effects of heat, with one exception: heat-exposed nestlings exhibited lower gene expression for superoxide dismutase, a key antioxidant defense. Despite this one apparent cost, our thorough organismal investigation indicates general resilience to a heatwave that may, in part, stem from behavioral buffering and acclimation. Our approach provides a mechanistic framework that we hope will improve understanding of species persistence in the face of climate change.
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References
Chapter
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  • Apr 2022
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The application of assisted migration as a climate change adaptation tactic: An evidence map and synthesis
Article
Full-text available
Assisted migration entails the human assisted movement of individuals to more climatically-suitable areas within or outside of their current species range to help species respond to climate change. To better understand the potential for assisted migration to benefit species threatened by climate change, we conducted an evidence synthesis to map examples where assisted migration has been implemented around the world. With this mapping exercise, we collate and describe the quantity and key characteristics of the available evidence base, including the taxa, species conservation status, locations, and contexts relating to the use of this conservation tactic. Findings from this exercise highlight that assisted migration has been implemented very few times as a conservation tactic, though assisted migration has been conducted experimentally (for research purposes) and inadvertently (e.g., for reforestation) much more frequently. Assisted migration was most common for plants (particularly trees), followed by birds, and was rarely implemented for other taxa. Our review highlights the need for more research on assisted migration, with particular emphasis on understanding the population- and community-level outcomes of these actions. Our discussion focuses on the potential for assisted migration of Canadian species but will be informative to those considering assisted migration in other jurisdictions.
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The use, and usefulness, of spatial conservation prioritizations
Article
Full-text available
  • Apr 2018
Spatial conservation prioritization is used globally to guide decision making with the aim of delivering the best conservation gain per unit investment. However, despite many publications on the topic, the extent to which this approach is used by decision makers has been unclear. To investigate the degree to which prioritization has been adopted by practitioners to guide conservation implementation we conducted an online survey, collecting data on the approaches used to develop prioritizations and the reported extent of translation to on‐the‐ground action. Using a cluster analysis, we identified two categories of prioritizations, those developed to advance the field (42% of responses) and those intended for implementation (58% of responses). Respondents reported 74% of the prioritizations intended for implementation had translated to on‐the‐ground action. Additionally, we identified strong collaboration between academics and practitioners in prioritization development, suggesting a bridging of the theory‐practice gap. We recommend continued collaboration and research into the effectiveness of prioritizations in delivering conservation impacts. This article is protected by copyright. All rights reserved. Open access link: https://onlinelibrary.wiley.com/doi/full/10.1111/conl.12459
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An integrated framework to identify wildlife populations under threat from climate change
Article
Full-text available
Climate change is a major threat to global biodiversity that will produce a range of new selection pressures. Understanding species responses to climate change requires an interdisciplinary perspective, combining ecological, molecular and environmental approaches. We propose an applied integrated framework to identify populations under threat from climate change based on their extent of exposure, inherent sensitivity due to adaptive and neutral genetic variation and range shift potential. We consider intraspecific vulnerability and population-level responses, an important but often neglected conservation research priority. We demonstrate how this framework can be applied to vertebrates with limited dispersal abilities using empirical data for the bat Plecotus austriacus. We use ecological niche modelling and environmental dissimilarity analysis to locate areas at high risk of exposure to future changes. Combining outlier tests with genotype-environment association analysis we identify potential climate-adaptive SNPs in our genomic dataset and differences in the frequency of adaptive and neutral variation between populations. We assess landscape connectivity and show that changing environmental suitability may limit the future movement of individuals, thus affecting both the ability of populations to shift their distribution to climatically suitable areas and the probability of evolutionary rescue through the spread of adaptive genetic variation among populations. Therefore a better understanding of movement ecology and landscape connectivity is needed for predicting population persistence under climate change. Our study highlights the importance of incorporating genomic data to determine sensitivity, adaptive potential and range shift potential, instead of relying solely on exposure to guide species vulnerability assessments and conservation planning.
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Climate-Related Local Extinctions Are Already Widespread among Plant and Animal Species
Article
Full-text available
Current climate change may be a major threat to global biodiversity, but the extent of species loss will depend on the details of how species respond to changing climates. For example, if most species can undergo rapid change in their climatic niches, then extinctions may be limited. Numerous studies have now documented shifts in the geographic ranges of species that were inferred to be related to climate change, especially shifts towards higher mean elevations and latitudes. Many of these studies contain valuable data on extinctions of local populations that have not yet been thoroughly explored. Specifically, overall range shifts can include range contractions at the “warm edges” of species’ ranges (i.e., lower latitudes and elevations), contractions which occur through local extinctions. Here, data on climate-related range shifts were used to test the frequency of local extinctions related to recent climate change. The results show that climate-related local extinctions have already occurred in hundreds of species, including 47% of the 976 species surveyed. This frequency of local extinctions was broadly similar across climatic zones, clades, and habitats but was significantly higher in tropical species than in temperate species (55% versus 39%), in animals than in plants (50% versus 39%), and in freshwater habitats relative to terrestrial and marine habitats (74% versus 46% versus 51%). Overall, these results suggest that local extinctions related to climate change are already widespread, even though levels of climate change so far are modest relative to those predicted in the next 100 years. These extinctions will presumably become much more prevalent as global warming increases further by roughly 2-fold to 5-fold over the coming decades.
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Incorporating climate change into spatial conservation prioritisation: A review
Article
Full-text available
To ensure the long-term persistence of biodiversity, conservation strategies must account for the entire range of cli- mate change impacts. A variety of spatial prioritisation techniques have been developed to incorporate climate change. Here, we provide the first standardised review of these approaches. Using a systematic search, we analysed peer-reviewed spatial prioritisation publications (n = 46) and found that the most common approaches (n = 41, 89%) utilised forecasts of species distributions and aimed to either protect future species habitats (n = 24, 52%) or identify climate refugia to shelter species from climate change (n = 17, 37%). Other approaches (n = 17, 37%) used well-established conservation planning principles to combat climate change, aimed at broadly increasing ei- ther connectivity (n = 11, 24%) or the degree of heterogeneity of abiotic factors captured in the planning process (n = 8, 17%), with some approaches combining multiple goals. We also find a strong terrestrial focus (n = 35, 76%), and heavy geographical bias towards North America (n = 8, 17%) and Australia (n = 11, 24%). While there is an increasing trend of incorporating climate change into spatial prioritisation, we found that serious gaps in cur- rent methodologies still exist. Future research must focus on developing methodologies that allow planners to incor- porate human responses to climate change and recognise that discrete climate impacts (e.g. extreme events), which are increasing in frequency and severity, must be addressed within the spatial prioritisation framework. By identi- fying obvious gaps and highlighting future research needs this review will help practitioners better plan for conser- vation action in the face of multiple threats including climate change.
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Climate change, species range shifts and dispersal corridors: An evaluation of spatial conservation models
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Full-text available
1.The notion that conservation areas are static geographical units for biodiversity conservation should be revised when planning for climate change adaptation. Since species are expected to respond to climate change by shifting their distributions, conservation areas can lose the very same species that justified their designation. Methods exist to take into account the potential effects of climate on spatial priorities for conservation. One of such methods involves the identification of time-ordered linkages between conservation areas (hereafter termed climate change corridors), thus enabling species tracking their suitable changing climates. 2.We critically review and synthesise existing quantitative approaches for spatial conservation planning under climate change. We extend these approaches focusing on the identification of climate change corridors, using three alternative models that vary on the objective function (minimum cost or maximum benefit sought) and on the nature of conservation targets (area-based or persistence probabilities). 3.The three models for establishing climate change corridors are illustrated with a case study involving two species distributed across the Iberian Peninsula. The species were modelled in relation to climate change scenarios using ensembles of bioclimatic models and theoretical dispersal kernels. The corridors obtained are compared for their location, the temporal sequence of priorities, and the effectiveness with which solutions attain persistence and cost objectives. 4.By clearly framing the climate change corridors problem as three alternative models and providing the corresponding mathematical descriptions and solving tools, we offer planners a wide spectrum of models that can be easily adapted to a variety of conservation goals and constraints.
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Should it be saved?
Article
  • Sep 2018
Proposals to focus resources on some endangered species and let others go extinct are stirring fierce debate.
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Conservation triage or injurious neglect in endangered species recovery
Article
  • Mar 2016
Significance Although government funding available for species protection and recovery is one of the best predictors of successful recovery, government spending is both insufficient and highly disproportionate among groups of species. Here I demonstrate that expenditures for recovery in excess of the recommended recovery budget would not necessarily translate into better conservation outcomes. More importantly, elimination of the budget surplus for “costly yet futile” recovery plans can provide sufficient funding to offset funding deficits for more than 180 species. Using a return on investment analysis, I show that triage by budget compression provides better funding for a larger sample of species, and that a larger sample of adequately funded recovery plans should produce better outcomes even if by chance.
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Restoration, Reintroduction, and Rewilding in a Changing World
Article
The increasing abandonment of marginal land creates new opportunities for restoration, reintroduction, and rewilding, but what do these terms mean in a rapidly and irreversibly changing world? The ‘re’ prefix means ‘back’, but it is becoming clear that the traditional use of past ecosystems as targets and criteria for success must be replaced by an orientation towards an uncertain future. Current opinions in restoration and reintroduction biology range from a defense of traditional definitions, with some modifications, to acceptance of more radical responses, including assisted migration, taxon substitution, de-extinction, and genetic modification. Rewilding attempts to minimize sustained intervention, but this hands-off approach is also threatened by rapid environmental change.
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