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Bobcat Population Status and Management in North America: Evidence of Large-Scale Population Increase

November 2010
Journal of Fish and Wildlife Management 1:169-174

DOI:10.3996/122009-JFWM-026

Authors:

Nathan M Roberts

College of the Ozarks

Shawn Crimmins

U.S. Geological Survey

Bobcat Lynx rufus populations are thought to be increasing in North America; however, little information exists on their current population status. In the United States, management and monitoring of bobcat populations is the responsibility of state wildlife management agencies. We surveyed state wildlife management agencies in each of the 48 contiguous states regarding the current population status, distribution, and monitoring protocols of bobcats within each respective jurisdiction. We also surveyed the governments of Mexico and Canada regarding bobcat population status within their jurisdictions. We received responses from 47 U.S. states, Mexico, and 7 Canadian provinces. Responses indicate that bobcats occur in each of the contiguous states except for Delaware. Populations were reported to be stable or increasing in 40 states, with 6 states unable to report population trends and only 1 state (Florida) reporting decreases in bobcat populations. Of the 47 states in which bobcats occur, 41 employ some form of population monitoring. Population density estimates were available for 2,011,518 km2(33.6%) of the estimated bobcat range in the United States, with population estimates between 1,419,333 and 2,638,738 individuals for this portion of their range and an estimated 2,352,276 to 3,571,681 individuals for the entire United States. These results indicate that bobcat populations have increased throughout the majority of their range in North America since the late 1990s and that populations within the United States are much higher than previously suggested.

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Surveys

Bobcat Population Status and Management in North

America: Evidence of Large-Scale Population Increase

Nathan M. Roberts,* Shawn M. Crimmins

N.M. Roberts

Department of Natural Resources, Cornell University, Ithaca, New York 14853

S.M. Crimmins

Department of Forest Management, University of Montana, Missoula, Montana 59812

Abstract

Bobcat Lynx rufus populations are thought to be increasing in North America; however, little information exists

on their current population status. In the United States, management and monitoring of bobcat populations

is the responsibility of state wildlife management agencies. We surveyed state wildlife management agencies in

each of the 48 contiguous states regarding the current population status, distribution, and monitoring protocols

of bobcats within each respective jurisdiction. We also surveyed the governments of Mexico and Canada regarding

bobcat population status within their jurisdictions. We received responses from 47 U.S. states, Mexico, and 7

Canadian provinces. Responses indicate that bobcats occur in each of the contiguous states except for Delaware.

Populations were reported to be stable or increasing in 40 states, with 6 states unable to report population trends

and only 1 state (Florida) reporting decreases in bobcat populations. Of the 47 states in which bobcats occur, 41

employ some form of population monitoring. Population density estimates were available for 2,011,518 km

(33.6%) of

the estimated bobcat range in the United States, with population estimates between 1,419,333 and 2,638,738

individuals for this portion of their range and an estimated 2,352,276 to 3,571,681 individuals for the entire United

States. These results indicate that bobcat populations have increased throughout the majority of their range in North

America since the late 1990s and that populations within the United States are much higher than previously

suggested.

Keywords: bobcat; Lynx rufus; monitoring; North America; population status

Received: December 13, 2009; Accepted: June 10, 2010; Published Online Early: June 2010; Published: November

2010

Citation: Roberts NM, Crimmins SM. 2010. Bobcat population status and management in North America: evidence of

large-scale population increase. Journal of Fish and Wildlife Management 1(2):169–174; e1944-687X. doi: 10.3996/

122009-JFWM-026

reproduced or copied without permission. Citation of the source, as given above, is requested.

The findings and conclusions in this article are those of the author(s) and do not necessarily represent the views of the

U.S. Fish and Wildlife Service.

* Corresponding author: nmr25@cornell.edu

Introduction

Bobcats Lynx rufus are one of the most widely spread

and adaptable carnivores in North America (Anderson

1987). Bobcats serve as a top predator in many

ecosystems (Conner et al. 2001) and can have significant

effects on ecosystem function. For example, bobcats

have been identified as a significant source of predation,

in specific systems, for white-tailed deer Odocoileus

virginianus (Nelms et al. 2001), cotton rats Sigmodon

hispidus (Schnell 1968), and pronghorn Antilocapra

americana (Beale and Smith 1973). Thus, in many

situations, proper management of bobcat populations

may be an important component of managing for

ecosystem function and biodiversity.

In the United States, management of bobcat popula-

tions is the responsibility of state wildlife management

agencies. However, management of bobcats, as with

many other carnivores, can be difficult due to their

elusive nature and the lack of information on demo-

Journal of Fish and Wildlife Management | www.fwspubs.org November 2010 | Volume 1 | Issue 2 | 169

Table 1. Bobcat monitoring methods (Monitoring), population estimates (N), range extent (Habitat, in km

), and population

status (Status; 1981–present) for selected jurisdictions in North America. NR indicates data were not reported by jurisdiction.

Monitoring methods were public sightings (PS), harvest analysis (HA), hunter surveys (HS), population models (PM), scent or sign

stations (SS), snow track surveys (TS), incidental harvest (IH), vehicle collisions analysis (VC), or other (OT).

Jurisdiction Monitoring

Habitat Status

United States

Alabama HA 68,625 116,550 Increasing

Arizona HA,HS 62,395–65,909 294,315 Increasing

Arkansas HS 14,049 134,874 Unknown

California NR 69,429–72,735 330,614 Stable

Colorado NR NR NR NR

Connecticut PS,VC Unknown 11,655 Increasing

Delaware - 0 - Absent

Florida NR 303,338 151,669 Decreasing

Georgia HA,SS 209,870–249,845 149,907 Increasing

Idaho NR 1,705–13,640 170,500 Increasing

Illinois HS 2,252 143,960 Increasing

Indiana PS,IH Unknown 92,434 Increasing

Iowa PM,OT 1,155–2,331 34,153 Increasing

Kansas HA,HS,SS 29,666–31,785 211,900 Increasing

Kentucky HA 14,000 102,896 Increasing

Louisiana HA,HS 66,431 112,825 Increasing

Maine HA Unknown 40,000 Stable

Maryland SS Unknown Unknown Increasing

Massachusetts NR Unknown 12,051 Unknown

Michigan HS,SS Unknown 116,550 Increasing

Minnesota HA,PM,SS,TS 2,857 103,600 Increasing

Mississippi HA 52,436 90,753 Increasing

Missouri HA,HS,SS 18,000–20,000 121,489 Increasing

Montana HA,TS 7,641 375,550 Increasing

Nebraska NR Unknown 171,000 Increasing

Nevada HA,PM Unknown 284,449 Stable/Increasing

New Hampshire HS,VC,IH Unknown 20,098 Increasing

New Jersey OT 106 1,600 Increasing

New Mexico HA,SS 36,249–54,373 181,243 Stable

New York PS,HA,HS 5,078 103,600 Increasing

North Carolina HA 90,115 126,161 Increasing

North Dakota HA Unknown 36,838 Unknown

Ohio PS Unknown 22,286 Increasing

Oklahoma HA Unknown 178,202 Increasing

Oregon None Unknown 248,630 Unknown

Pennsylvania HA,VC,IH,PS,PM 18,766 85,300 Increasing

Rhode Island PS,VC Unknown Unknown Unknown

South Carolina HA,SS 40,552–94,622 56,773 Stable

South Dakota HA,PM Unknown 100,000 Increasing

Tennessee HA Unknown 106,739 Stable

Texas HA 287,444–1,357,928 495,594 Stable

Utah HA Unknown 202,020 Stable

Vermont HA 2,100–3,500 23,310 Increasing

Virginia HA Unknown 64,118 Increasing

Washington NR Unknown 170,000 Stable

West Virginia HA 8,743 56,656 Increasing

Wisconsin HA,HS,PM,TS 2,850 46,620 Increasing

Bobcat Status and Management in North America N.M. Roberts and S.M. Crimmins

Journal of Fish and Wildlife Management | www.fwspubs.org November 2010 | Volume 1 | Issue 2 | 170

graphic rates. Changes in bobcat management in

response to population trends are common (Rolley et

al. 2001); however, most population assessments or

studies of bobcat range have been limited in geographic

scope (e.g., Woolf et al. 2002). It is generally assumed by

managers that a harvest rate of 20% is sustainable (Knick

1990), but that variability in environmental factors may

confound this (Anderson and Lovallo 2003). The vast

geographic range of bobcats in North America highlights

the need for large-scale population assessments. Bluett

et al. (2001) reported that state agencies considered

distribution and relative abundance to be among the

most important research topics for bobcats.

Woolf and Hubert (1998) provided the most recent

assessment of bobcat population distribution and

management in North America, with the most recent

range-wide population assessment occurring in 1981

(USFS 1981). However a more contemporary assess-

ment is needed because human populations and

development have increased greatly during the past

decades. Although numerous regional or local studies

have suggested that bobcat populations are increasing

(e.g., Woolf et al. 2000), no empirical evidence of range-

wide increases in population abundance exists. Our

objective was to document monitoring efforts, spatial

distribution, and population trends of bobcats in North

America.

Methods

Agency surveys

We contacted wildlife management agencies from all

of the 48 contiguous states of the United States, 7

Canadian provinces (British Columbia, Manitoba, New

Brunswick, Nova Scotia, Ontario, Quebec, Saskatchewan),

and the country of Mexico in 2008. Each jurisdiction was

asked to report: 1) what methods are employed to

monitor bobcat status, 2) population estimates and

average densities (if available), 3) the area (reported here

in km

) of suitable bobcat habitat within the jurisdiction,

and 4) post-1981 population trends. Monitoring methods

were classified as public sightings, harvest analysis,

hunter surveys, population models, scent or sign

stations, snow track surveys, incidental harvest, vehicle

collisions analysis, or other. We primarily present

information from U.S. states to facilitate comparison

with previous studies and population estimates (USFWS

1982; Woolf and Hubert 1998) and for brevity.

Data analysis

We compared the proportion of states reporting

increasing or stable populations between 1996 and

2008 (Woolf and Hubert 1998) using chi-square tests. We

only included states that reported population trends in

this analysis. States that reported populations as ‘‘stable/

increasing’’ were assigned a status of ‘‘stable’’ for this

analysis. We estimated minimum population abundance

and total suitable habitat as the sum of population or

habitat estimates across all jurisdictions. Because not all

states reported estimated population abundance (n=

26) or area of suitable habitat (n= 5), we considered

these minimum estimates to be very conservative. To

estimate total population abundance across the contig-

uous United States, we calculated average bobcat

density for those states reporting both population and

area of habitat estimates and then multiplied this

average by the geographic range estimates for all states

that reported range estimates but no population

estimates (n= 17) and added this value to the minimum

count. This method provided a general estimate of

population abundance across the entire United States

that facilitates comparison with historic estimates that

used similar methods (USFWS 1982).

Results

We received responses from 47 of the 48 states, 7

Canadian provinces, and Mexico. Responses indicated

total area of suitable bobcat habitat of 8,708,888 km

with 71% (6,186,819 km

) in the United States, 20% in

Mexico (1,702,545 km

), and 9% in Canada (819,524 km

Twenty-eight (50.9%) of the jurisdictions reported

population estimates or densities (Table 1). Of the 48

jurisdictions that reported population trends, 31 (64.6%)

reported increasing populations while 15 (31.3%) report-

ed stable populations, and 1 reported fluctuating

populations. Only one jurisdiction, Florida, reported

decreasing bobcat populations (Figure 1). The minimum

population estimate in the United States was between

1,418,333 and 2,637,738 individuals, representing 68.4%

of the total estimated bobcat range in the United States

(Table 1). Using average density, the total population

Table 1. Continued.

Jurisdiction Monitoring

Habitat Status

Wyoming HA,SS 2,481–13,783 253,601 Increasing

Canada

British Columbia HA Unknown NR Stable

Manitoba NR Unknown NR Stable

New Brunswick HA,TS,OT Unknown 72,784 Stable

Nova Scotia HA,OT 5,170–9,910 43,086 Fluctuating

Ontario HA Unknown 400,015 Stable

Quebec PS,IH Unknown 55,000 Stable/Increasing

Saskatchewan HA,HS Unknown 248,639 Stable

Mexico NR Unknown 1,702,545 Unknown

Bobcat Status and Management in North America N.M. Roberts and S.M. Crimmins

Journal of Fish and Wildlife Management | www.fwspubs.org November 2010 | Volume 1 | Issue 2 | 171

abundance in the United States was estimated to be

between 2,352,276 and 3,571,681 individuals. A signifi-

cantly higher (x

= 5.64, P= 0.018, df = 1) proportion of

states reported increasing populations in 2008 than in

1996.

Of the 55 jurisdictions surveyed, 45 (81.2%) reported

methods used to monitor bobcat populations, 25 (55.6%)

of which used .1 method. Harvest data analysis and

hunter surveys were the most commonly used methods

(Table 2). No jurisdiction used .5 methods to monitor

bobcats. Only one jurisdiction (Oregon) reported having

bobcat populations but no monitoring method.

Discussion

Bobcats are highly adaptable carnivores and are the

most abundant of North America wild felids (Cowan

1971; Anderson and Lovallo 2003). Their ecological role

and economic value as furbearers are the primary

motivations behind research and management of

bobcats (Woolf and Nielsen 2001). Woolf and Hubert

(1998) reported that less than half of the states in the

contiguous United States (n= 20) had increasing bobcat

populations as of 1996; however, we found that 32 states

now report increasing populations (Table 1). All other

states that reported bobcat population trends, with the

exception of Florida, reported at least stable populations.

Although the magnitude of population increase likely

varies considerably among jurisdictions, the general trend

supports the hypothesis that bobcat populations are

expanding across much of their geographic range. The

reason for declining populations in Florida is unknown,

although extensive human development may be partly

responsible. Given the stability of bobcat populations

elsewhere in the United States, the decreasing population

in Florida does not pose any immediate threat to the

large-scale persistence of bobcat populations in the

United States. However, research into the vital rates and

demographic patterns of the Florida bobcat population

could provide useful information to wildlife managers if

populations elsewhere begin declining.

Minimum population estimates provided by jurisdic-

tions indicated that the United States’ bobcat population

is .1.4 million. This estimate is likely a substantial

underestimation of total population abundance, because

it only represented population estimates for approxi-

mately 68% of the reported bobcat range. In 1981 similar

methods were used to estimate bobcat populations; at

that time it was estimated there were 725,000–1,017,000

bobcats in the United States (USFWS 1982). Using these

methods, our data indicate that current bobcat popula-

tion abundance in the entire United States is 2,352,276–

3,571,681. This growth is likely the result of many factors

including changing agricultural and land-use practices,

range expansion, and habitat improvement programs

such as the Conservation Reserve Program (FSA 1985, 16

U.S.C. 3831). In addition, advances in wildlife manage-

ment and monitoring have allowed states to greatly

improve wildlife management programs in recent

decades, particularly furbearer management. As recently

as 1971, 40 of the 48 contiguous United States had no

protection or formal management of bobcats (Faulkner

1971). In New York, for example, bobcats were desig-

nated as an unprotected species and take was unregu-

lated through 1976, only 5 y prior to the 1981 population

estimate (USFWS 1982). After 1976, bobcats were

afforded legal status as a furbearer species to be

conserved, and harvest regulations were developed

and implemented. Similar shifts in management para-

digms have occurred in many jurisdictions; these have

clearly benefited bobcat populations. Bobcat harvests

did increase during 1976–1984, but recent harvest levels

are comparable to those three decades earlier (36,674

harvested during 1997–1998 verses 37,026 during 1975–

1976), despite this increase in population size (Associa-

tion of Fish and Wildlife Agencies, unpublished data).

This is likely due to decreased harvest effort.

Because population survey methods were not stan-

dardized across jurisdictions, there is likely substantial

variability in the accuracy of the estimates provided by

management agencies. For example, only six states used

any form of population model in their monitoring of

bobcat populations, likely because of the paucity of

accurate data available for developing such models.

Similarly, 19 states failed to report population estimates.

Although this variability may be substantial, it does not

preclude comparison to previous reports (USFWS 1982)

or interpretation of jurisdiction-specific population

Table 2. Methods used to monitor bobcat populations in

the lower 48 states and 7 Canadian provinces in 2008 (45

jurisdictions reporting). Twenty-five jurisdictions used .1

method.

Method No. of jurisdictions

Harvest data analysis 33

Public sightings 7

Hunter surveys 11

Population models 6

Scent or sign stations 9

Snow track surveys 4

Incidental harvest 4

Vehicle collision analysis 4

Other 4

None 1

Figure 1. Bobcat population trends in the contiguous United

States, 2004.

Bobcat Status and Management in North America N.M. Roberts and S.M. Crimmins

Journal of Fish and Wildlife Management | www.fwspubs.org November 2010 | Volume 1 | Issue 2 | 172

trends. Agency surveys such as this provide the only

feasible means of providing range-wide population

assessments, because field-based surveys would be

logistically and financially impractical. Although the level

of detail in such surveys is limited, they can provide a

cost-effective means to estimate large-scale population

trends. At the statewide scale, harvest surveys were the

most commonly used approach for monitoring bobcat

populations, which is not surprising given that these

data can be obtained for large geographic areas at

relatively low costs. Unlike harvest analysis or scent

stations, methods such as hunter surveys that do not

require market-based incentives or extensive field labor

may be more practical methods for monitoring bobcat

population trends.

As with many species, enumeration of population

abundance is not required for proper management.

Within jurisdictions, specific monitoring programs can be

implemented if needed. In the United States, 41 states

currently monitor bobcat population status or trends,

despite the fact that only one state reported bobcat

populations as declining. Population models, archer

surveys, hunter surveys, harvest data, field studies,

scent-post surveys, sign-station surveys, public sightings,

and detection dogs are all techniques used in North

America to monitor bobcat populations (Bluett et al.

2001; Anderson and Lovallo 2003). The majority of

jurisdictions that reported monitoring methods used

multiple methods (Table 2). The number of jurisdictions

monitoring bobcat populations, and the number of

methods used, is similar to previous reports (Woolf and

Hubert 1998). The number of jurisdictions reporting

increasing bobcat populations has increased from 20 to

32 since 1996 (Woolf and Hubert 1998), and overall

population estimates for the United States have more

than doubled since 1981 (USFWS 1981). Similarly, six of

the seven Canadian provinces reported stable bobcat

populations.

Bobcat populations are more widely distributed and

more abundant than they were in 1981. These increases

are likely attributable primarily to multiple factors

including habitat availability, increased prey density,

changing land-use practices, and intense harvest man-

agement at the state level. Standardization of monitoring

and density-estimation techniques would increase the

robustness of future comparisons. Thus, we suggest that

jurisdictions focus on developing standardized methods

for assessing bobcat distribution and abundance.

Acknowledgments

We thank the state, provincial, and national wildlife

management agencies for providing the data for this

analysis. The Ohio Division of Wildlife facilitated the

distribution and collection of the surveys. Logistical

support was provided by the Department of Natural

Resources at Cornell University and the Department of

Forest Management at the University of Montana. We

also thank the two anonymous reviewers and the

Subject Editor for providing valuable comments that

improved the quality of the manuscript.

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Full-text available

Apr 2024

Simple Summary Hunting can have direct effects (i.e., mortality) and indirect effects (i.e., behavior changes, such as shifting away from foraging areas to circumvent risk from hunters) on white-tailed deer (Odocoileus virginianus). Deer populations within the Chattahoochee National Forest of northern Georgia, USA, have declined significantly since the 1980s. Since deer population sustainability is a concern, understanding the potential negative effects of hunting on female deer is important. During the 2018–2019 and 2019–2020 hunting seasons, we evaluated the indirect effects of 7 firearms hunts for male deer on 20 non-target female deer. We used GPS locations recorded every 30 min during pre-hunt, hunt, and post-hunt periods to calculate and compare movement rates during the day and night, as well as the size and landscape characteristics of the space the deer utilized. Our results suggest that the low level of hunting pressure in our study area led to no biologically significant changes in female deer movements. To the extent of the findings presented in this paper, adjustments to the management of hunting in our study area do not appear to be necessary to minimize hunting-related disturbances for female deer. However, managers should continue to consider female deer behavior when evaluating future changes to hunting regulations. Abstract Perceived risk associated with hunters can cause white-tailed deer (Odocoileus virginianus) to shift their activity away from key foraging areas or alter normal movements, which are important considerations in managing hunting and its effects on a population. We studied the effects of seven firearms hunts on the movements of 20 female deer in two Wildlife Management Areas within the Chattahoochee National Forest of northern Georgia, USA, during the 2018–2019 and 2019–2020 hunting seasons. Deer populations and the number of hunters in our study area have declined significantly since the 1980s. In response, hunting regulations for the 2019–2020 hunting season eliminated opportunities for harvesting female deer. To evaluate the indirect effects of antlered deer hunting on non-target female deer, we calculated 90% utilization distributions (UDs), 50% UDs, and step lengths for pre-hunt, hunt, and post-hunt periods using the dynamic Brownian bridge movement model. Data included 30 min GPS locations for 44 deer-hunt combinations. Pre-hunt 50% UDs (x− = 7.0 ha, SE = 0.4 ha) were slightly greater than both hunt (x− = 6.0 ha, SE = 0.3 ha) and post-hunt (x− = 6.0 ha, SE = 0.2 ha) 50% UDs (F = 3.84, p = 0.03). We did not detect differences in step length, nor did we detect differences in size or composition of 90% UDs, among the periods. Overall, our results suggest that the low level of hunting pressure in our study area and lack of exposure to hunters led to no biologically significant changes in female deer movements. To the extent of the findings presented in this paper, adjustments to the management of hunting in our study area do not appear to be necessary to minimize hunting-related disturbances for female deer. However, managers should continue to consider female deer behavior when evaluating future changes to hunting regulations.

Urbanisation and Host Relatedness Shape Virome Composition in a Widespread, Generalist Carnivore

Article

Feb 2025
MOL ECOL

Urban wildlife species have the potential to serve as links in disease transmission between wildlife, humans and domestic animals at the wildland–urban interface (WUI), contributing to both sustained cross-species transmission of pathogens and the emergence of diseases in susceptible populations. However, the relative roles of host and environmental factors in shaping the composition of pathogen communities in urban wildlife is understudied. In this study, we integrated DNA and RNA virome data with host genomic and GPS datasets to investigate factors shaping virome composition in bobcats (Lynx rufus ) at the WUI in the Tucson Mountains, Arizona, USA. Using a hybrid-capture approach for 31 scats and 17 buccal swabs, we identified multiple viruses that could affect carnivore health at the WUI, including canine parvovirus, feline astrovirus, Felis catus papillomaviruses 2 and 3 and Lyon-IARC polyomavirus. Models of virome composition and distribution of viral taxa indicated contributions of host genetic relatedness and factors relating to urbanisation (such as percentages of urban land cover, road and building densities and distances to roads). Genetic associations with virome compositions were particularly influenced by females. While females exhibit significant isolation by distance, partial Mantel tests revealed a significant correlation between beta diversity and host genetic distance in females only. To our knowledge, this study represents the first assessment of factors shaping virome composition in a wild felid. Our finding of known feline and canine pathogens in bobcats underscores the potential of the WUI to facilitate cross-species transmission between wild and domestic animals.

Evidence of extensive home range sharing among mother–daughter bobcat pairs in the wildland–urban interface of the Tucson Mountains

Article

Dec 2024

Urbanization impacts the structure and viability of wildlife populations. Some habitat generalists, such as bobcats (Lynx rufus), maintain populations at the intersection of wild and urban habitats (wildland–urban interface), but the impacts of urbanization on bobcat social structure are not well understood. Although commonly thought to establish exclusive home ranges among females, instances of mother–daughter home range sharing have been documented. We combined Global Positioning System (GPS) localities with genomic relatedness inferences from double-digest restriction site associated DNA sequencing to investigate mother–daughter home range sharing in bobcats (n = 38) at the wildland–urban interface in the Tucson Mountains, Arizona, USA. We found the highest relatedness among females, which showed stronger isolation by distance than males and the population as a whole. Using mother–daughter relationships inferred from pedigree reconstruction, we found extensive mother–daughter home range sharing, compared with other females. Every mother identified as having at least one daughter, shared home ranges with one daughter, while other confirmed daughters established adjacent home ranges. Our results provide substantial support for the mother–daughter home range sharing hypothesis, as well as evidence of spatiotemporal overlap between mothers and daughters, adding to the body of research complicating the solitary felid paradigm. These results additionally challenge the notion of home range partitioning by prior-rights land tenure, suggesting a role of matrilineal land tenure in the home range establishment of daughters. Habitat fragmentation due to human population growth and urbanization thus has the potential to alter landscape genetic structure and social dynamics in bobcats.

First density estimates for a recovering bobcat population in Ohio using DNA from scat

Article

Mar 2024

The recovery of mammalian species in the US Midwest through natural recolonization constitutes a conservation success story, yet management remains challenging due to many unknowns related to population dynamics and numeric trends. Abundance is a critical parameter for management decisions, and estimating the density and abundance of elusive species, such as terrestrial carnivores, remains challenging despite recent technological advances. In this study, we evaluated density and abundance of a recovering carnivore species, the bobcat ( Lynx rufus ) in two areas of Ohio using non‐invasive DNA from scat. The target areas in eastern and southern Ohio have been shown to have uneven dynamics and recolonization success and we expected that this would be reflected in differences in density and abundance. We collected 298 bobcat scats between July 2018 and April 2019 on 150 km of repeated transects. Of these, 102 scats were successfully genotyped, and 55 individuals were identified (33 in eastern Ohio and 22 in southern Ohio). Using Spatially Explicit Capture–Recapture models, we estimated 18.9 ± 4.1 and 10.9 ± 2.7 bobcats/100 km ² in eastern and southern Ohio study areas, respectively. Our results support prior telemetry data which indicated that bobcats in eastern Ohio had smaller home‐ranges than bobcats in southern Ohio, and thus could support a higher density of individuals. The higher densities were similar to other eastern US populations and are much higher than other Midwestern recovering populations. Our results provide a snapshot of the population status and can be used to determine sustainable management strategies for Ohio's bobcat population.

Factors influencing population growth in a bobcat population

Article

Full-text available

Feb 2024

Bobcats (Lynx rufus) are the most broadly distributed native felid in North America and have substantial ecological and economic importance. Despite this importance, little is known about factors influencing population dynamics of this cryptic carnivore. Given recent apparent declines in abundance, we investigated population growth rate (λ) for a bobcat population in the Black Hills, South Dakota, USA, 2016-2022. We constructed and evaluated a females-only matrix population model. Our estimate of asymptotic λ, derived from estimates of vital rates obtained over 6 years, was 0.85 (95% CI = 0.72, 1.02), which indicates that the vital rates in 2016-2022 were inadequate to sustain the population. Elasticity and sensitivity values were highest for changes in adult survival probability followed by, in order, changes in kitten and juvenile survival and adult reproductive contribution. Life-stage simulation analysis also supported that adult survival was most important; however, the juvenile survival (91 day-1 year) component of a bobcat's first year of life was also important and a stronger influence on population growth than the kitten survival (first 90 days) component. For the combination of survival and reproductive rates we estimated positive population growth required either annual adult survival >0.85 or 275-day juvenile survival >0.35, regardless of other vital rates. When assuming a baseline harvest rate of 23.5%, reducing the harvest rate to Journal of Wildlife Management 2024;e22561. wileyonlinelibrary.com/journal/jwmg |

Ареали. Ссавці. Частина 1 : навчальний посібник

Book

Full-text available

Dec 2023

У навчальному посібнику детально розглянуто представників чоти-рьох родин хижаків, зокрема ведмедевих, псових (вовчих), котових (котя-чих) і мустелових (куницевих). Подано загальні відомості про тварин, ареа-ли їх поширення, спосіб життя, розмноження, харчування. Висвітлено про-блеми збереження і приналежність до видових категорій згідно з Червоним списком Міжнародного союзу охорони природи. Для студентів і викладачів географічних факультетів вищих закладів освіти, майбутніх фахівців у галузі географії і природничих наук, усіх, хто цікавиться життям тварин.

Multivariate habitat models for bobcats in southern forested landscapes

Article

Full-text available

Jan 2001

Status and management of bobcats in the United States over three decades: 1970s-1990s

Article

Jun 1998

Mortality of Pronghorn Antelope Fawns in Western Utah

Article

Jul 1973

Over a period of 5 years 117 pronghorn antelope (Antilocapra americana) fawns 1-5 days of age were captured in a 4,000-hectare enclosure and fitted with radio transmitters to provide a means of relocating them to determine causes of mortality. Each fawn was located and observed daily until approximately 4 months of age or until death. Fawns with transmitters that functioned beyond this period were thereafter checked periodically. A total of 55 cases of fawn mortality were discovered during the study. Bobcats (Lynx rufus) accounted for 27 deaths; golden eagles (Aquila chrysaetos) one; and coyotes (Canis latrans) one. Two died from salmonellosis, three from pneumonia, four from starvation, and one from an esophageal injury. Five died from unknown causes and eleven were abandoned by does as a result of handling. The ages of fawns definitely killed by bobcats ranged from 3 to 104 days; one weighed 22 kg at the time of kill.

The Limiting Effects of Natural Predation on Experimental Cotton Rat Populations

Article

Oct 1968

Jay H. Schnell

Survival curves for 2- to 6-month periods were plotted for 17 different populations of nonbreeding cotton rats (Sigmodon hispidus) introduced into isolated or enclosed areas of natural habitat. Eight populations were introduced onto predator-free islands or into a 1-acre, predator-proofed enclosure of old field habitat, and nine populations were released into 1-acre enclosures freely accessible to bird and mammal predators. Radioactive pins (cobalt-60 or zinc-65) inserted under the skin aided in determining the fate of cotton rats which failed to appear in live traps. Survival curves were linear or convex for introduced populations protected from predation and strongly concave for those open to natural predators. Abundant evidence for kills by hawks, foxes, and bobcats was found in the latter cases. A density of about 15/acre, the mean point of inflection in the survival curves, was considered to be a "predator-limited carrying capacity" since mortality was high above, and low below, this density when predators were active. The experimental study has special relevance to the fall and winter cotton rat populations in the southeastern United States. It is concluded that when diverse and highly mobile predator populations are present they are more important than food, social interaction, or weather in regulating cotton rat density.

Statewide modeling of bobcat, Lynx rufus, habitat in Illinois, USA

Article

Apr 2002
BIOL CONSERV

We used sighting location and remotely sensed habitat data, multivariate statistical techniques, and a geographic information system to model bobcat (Lynx rufus) habitat in Illinois, thereby providing state wildlife managers with information to review the listing of bobcats as a state-threatened species and contribute to the development of a statewide management plan. We used canonical discriminant function analysis to model presence/absence and relative abundance of bobcats statewide. These models suggested that bobcats occurred in moderate to high abundance in 23 of 98 counties statewide (23%). We used stepwise logistic regression (SLR) analysis to model statewide habitat suitability. Spatial modeling of the SLR equation predicted that 29% of Illinois contained suitable habitat classified as P>0.50. Models were accurate when validated with an independent data set and indicated the importance of woods-related habitat variables to bobcats. In conclusion, these models provided tools to rapidly assess status that contributed to delisting bobcats as a threatened species in Illinois and provided further information to guide conservation efforts.

The legal status of wildcats in the United States

Jan 1971

C E Faulkner

Faulkner CE. 1971. The legal status of wildcats in the United States. Pages 124-125 in Jorgensen RM, Mech LD, editors. Proceedings of a Symposium on the Native Cats of North America, Their Status and Management. 36th American Wildlife and Natural Resources Conference. Twin Cities, Minnesota: U.S. Fish and Wildlife Service. Available from the corresponding author.

Ecology of bobcats relative to exploitation and a prey decline in southeastern Idaho

Jan 1990
WILDLIFE MONOGR

S Knick

Knick S. 1990. Ecology of bobcats relative to exploitation and a prey decline in southeastern Idaho. Wildlife Monographs 108.

A critical review and annotated bibliography of literature on the bobcat

Jan 1987

E M Anderson

Anderson EM. 1987. A critical review and annotated bibliography of literature on the bobcat. Colorado Division of Wildlife Special Report 62. Available from the corresponding author.

Summary of the symposium on the native cats of North America Pages 2–8 in

Jan 1971

Im Cowan

Cowan IM. 1971. Summary of the symposium on the native cats of North America. Pages 2–8 in Jorgensen RM, Mech LD, editors. Proceedings of a Symposium on the Native Cats of North America, Their Status and Management. 36th American Wildlife and Natural Resources Conference. Twin Cities, Minnesota: U.S. Fish and Wildlife Service. Available from the corresponding author.

Proposal to remove the bobcat from Appendix II of the Convention on International Trade in Endangered Species of Wild Fauna and Flora

Jan 1982
1242-1246

U S Fish
Wildlife Service

U.S. Fish and Wildlife Service. 1982. Proposal to remove the bobcat from Appendix II of the Convention on International Trade in Endangered Species of Wild Fauna and Flora. Federal Register 47(6):1242-1246.