Integrating sign surveys and telemetry data for estimating brown bear (Ursus arctos) density in the Romanian Carpathians

Accurate population size estimates are important information for sustainable wildlife management. The Romanian Carpathians harbor the largest brown bear (Ursus arctos) population in Europe, yet current management relies on estimates of density that lack statistical oversight and ignore uncertainty deriving from track surveys. In this study, we investigate an alternative approach to estimate brown bear density using sign surveys along transects within a novel integration of occupancy models and home range methods. We performed repeated surveys along 2‐km segments of forest roads during three distinct seasons: spring 2011, fall‐winter 2011, and spring 2012, within three game management units and a Natura 2000 site. We estimated bears abundances along transects using the number of unique tracks observed per survey occasion via N‐mixture hierarchical models, which account for imperfect detection. To obtain brown bear densities, we combined these abundances with the effective sampling area of the transects, that is, estimated as a function of the median (± bootstrapped SE) of the core home range (5.58 ± 1.08 km²) based on telemetry data from 17 bears tracked for 1‐month periods overlapping our surveys windows. Our analyses yielded average brown bear densities (and 95% confidence intervals) for the three seasons of: 11.5 (7.8–15.3), 11.3 (7.4–15.2), and 12.4 (8.6–16.3) individuals/100 km². Across game management units, mean densities ranged between 7.5 and 14.8 individuals/100 km². Our method incorporates multiple sources of uncertainty (e.g., effective sampling area, imperfect detection) to estimate brown bear density, but the inference fundamentally relies on unmarked individuals only. While useful as a temporary approach to monitor brown bears, we urge implementing DNA capture–recapture methods regionally to inform brown bear management and recommend increasing resources for GPS collars to improve estimates of effective sampling area.     

Grizzly bear population vital rates and trend in the Northern Continental Divide Ecosystem,Montana

We estimated grizzly bear (Ursus arctos) population vital rates and trend for the Northern Continental Divide Ecosystem (NCDE), Montana, between 2004 and 2009 by following radio-collared females and observing their fate and reproductive performance. Our estimates of dependent cub and yearling survival were 0.612 (95% CI = 0.300–0.818) and 0.682 (95% CI = 0.258–0.898). Our estimates of subadult and adult female survival were 0.852 (95% CI = 0.628–0.951) and 0.952 (95% CI = 0.892–0.980). From visual observations, we estimated a mean litter size of 2.00 cubs/litter. Accounting for cub mortality prior to the first observations of litters in spring, our adjusted mean litter size was 2.27 cubs/litter. We estimated the probabilities of females transitioning from one reproductive state to another between years. Using the stable state probability of 0.322 (95% CI = 0.262–0.382) for females with cub litters, our adjusted fecundity estimate (m_x) was 0.367 (95% CI = 0.273–0.461). Using our derived rates, we estimated that the population grew at a mean annual rate of approximately 3% (λ = 1.0306, 95% CI = 0.928–1.102), and 71.5% of 10,000 Monte Carlo simulations produced estimates of λ > 1.0. Our results indicate an increasing population trend of grizzly bears in the NCDE. Coupled with concurrent studies of population size, we estimate that over 1,000 grizzly bears reside in and adjacent to this recovery area. We suggest that monitoring of population trend and other vital rates using radioed females be continued. © 2011 The Wildlife Society.     

Range and local population densities of brown bear Ursus arctos in Slovenia

Solid understanding of species’ range and local population densities is important for successful wildlife management and research. Specific behavioral and ecological characteristics make brown bear Ursus arctos a difficult species to study. We present a map of range and local population densities of brown bears in Slovenia, made with the use of a new approach similar to voting classifications based on a combination of four datasets: Global Positioning System telemetry data, records of bear removals, systematic and opportunistic direct observations and signs of bear presence, and noninvasive genetic samples. Results indicate that the majority of bears in Slovenia live in Dinaric Mountains in the southern part of the country where local bear population densities exceed 40 bears/100 km². This is one of the highest population densities reported so far for this species worldwide. Population densities decrease towards the north (Alpine region) and are very low along the border with Italy and Austria where almost no females are present. This explains slow past and present expansion of this transboundary bear population into the Alps and should be considered in future bear re-colonization management strategies. Results also showed that data from observations and removals overestimate bear population densities at low values, while mortality and genetic data overestimate population densities in areas with more people. Nevertheless, all data types appeared useful for describing the general bear distribution patterns. Similar approach could be applied to studies of other charismatic or game species, for which several types of data are often available.     

Safe space in the woods: Mechanistic spatial models for predicting risks of human–bear conflicts in India

Human–wildlife interactions can have negative consequences when they involve large carnivores. Spatial risk modelling could serve as a useful management approach for predicting and pre-emptively mitigating negative interactions. We present a mechanistic modelling framework and examine interactions between humans and sloth bears (Melursus ursinus) in a multi-use forest landscape of central India. We first assessed patterns and determinants of bear distribution across the landscape using indirect sign surveys. At the same spatial scale, we then estimated spatial probabilities of bear attacks on people using information from 675 interviews with local residents, incorporating estimates of distribution probabilities from the previous step. We found the average occupancy probability across 128 grid-cells to be 0.77 (SE = 0.03). Bear occupancy was influenced by terrain ruggedness, forest composition and configuration, vegetation productivity and size of human settlements. The average probability of a bear attack in any given grid-cell was 0.61 (SE = 0.03), mostly determined by bear occurrence patterns, forest cover, terrain ruggedness, and size of human settlements. Using spatial information on people's dependence on forest resources, we identified locations with the highest risk of bear attacks. Our study demonstrates that human attacks by bears—generally believed to be random or incidental—in fact showed deterministic patterns. Our framework can be applied to other scenarios involving human–wildlife conflicts. Based on our findings, we propose that a proactive co-management approach which involves collaboration between wildlife managers and local residents could help better manage human–bear conflicts in central India and elsewhere across the species' range.     

Introgressive hybridization: brown bears as vectors for polar bear alleles

The dynamics and consequences of introgression can inform about numerous evolutionary processes. Biologists have therefore long been interested in hybridization. One challenge, however, lies in the identification of nonadmixed genotypes that can serve as a baseline for accurate quantification of admixture. In this issue of Molecular Ecology, Cahill et al. (2015) analyse a genomic data set of 28 polar bears, eight brown bears and one American black bear. Polar bear alleles are found to be introgressed into brown bears not only near a previously identified admixture zone on the Alaskan Admiralty, Baranof and Chichagof (ABC) Islands, but also far into the North American mainland. Elegantly contrasting admixture levels at autosomal and X chromosomal markers, Cahill and colleagues infer that male‐biased dispersal has spread these introgressed alleles away from the Late Pleistocene contact zone. Compared to a previous study on the ABC Island population in which an Alaskan brown bear served as a putatively admixture‐free reference, Cahill et al. (2015) utilize a newly sequenced Swedish brown bear as admixture baseline. This approach reveals that brown bears have been impacted by introgression from polar bears to a larger extent (up to 8.8% of their genome), than previously known, including the bear that had previously served as admixture baseline. No evidence for introgression of brown bear into polar bear is found, which the authors argue could be a consequence of selection. Besides adding new exciting pieces to the puzzle of polar/brown bear evolutionary history, the study by Cahill and colleagues highlights that wildlife genomics is moving from analysing single genomes towards a landscape genomics approach.     

Brown Bear Density and Estimated Harvest Rates in Northwestern Alaska

Human-caused mortality in general, and unregulated hunting in particular, have been implicated in reductions in brown bear (Ursus arctos) populations throughout much of their range. In northwestern Alaska, USA, bear densities have not been assessed in 20 years while harvest regulations have been liberalized, raising concerns that broad undetected population declines might occur. We used a modified mark-resight approach to estimate brown bear density during 2005–2018 in 4 subareas throughout the region. We also summarized harvest information for each subarea and used our survey results to estimate harvest rates. We estimated densities for independent bears assuming constant or heterogeneous probabilities of detection and occurrence. We present the results of the constant model for more direct comparison with past work and the heterogeneity model results to provide estimates of density that are less likely to be negatively biased. Using the constant model, we estimated the density of independent bears was 17.0, 49.2, 24.9, and 19.4/1,000 km² on portions of the Seward Peninsula, the lower Noatak River, the upper Noatak River, and Gates of the Arctic National Park and Preserve, respectively. These estimates are broadly similar to those from past work in interior and northwestern Alaska, with the exception of the lower Noatak River subarea where our estimates are the highest reported for a bear population in northern Alaska. We estimated that the harvest rate on the Seward Peninsula was approximately 5.2% or 7.7% on average, depending upon the model used. In the remaining areas, we estimated annual harvest rates were <2.5%, well within sustainability guidelines from past work. Overall, our results suggest that brown bear densities are similar or somewhat higher than in the past in much of northwestern Alaska and that current harvest rates are sustainable in most areas, except perhaps the Seward Peninsula. Ongoing survey work will be useful for further evaluating the assumptions of the modified mark-resight survey approach, assessing population trajectory, and determining the effect of harvest on brown bear populations. © 2021 The Wildlife Society.     

Use of Occupancy Models to Estimate the Influence of Previous Live Captures on DNA-Based Detection Probabilities of Grizzly Bears

Abstract: Large carnivores potentially change their behavior following physical capture, becoming less responsive to the attractants that resulted in their capture, which can bias population estimates where the change in behavior is not appropriately modeled. We applied occupancy models to efficiently estimate and compare detection probabilities of previously collared grizzly bears (Ursus arctos) with bears captured at DNA hair-snag sites that were not previously collared. We found that previously captured bears had lower detection probabilities, although their detection probabilities were still >0, implying that they were still visible to be sampled via the DNA hair-snag grid, which was able to detect finer differences in capture probabilities of previously collared bears compared with Huggins closed-captures population models. To obtain relatively unbiased population estimates for DNA surveys, heterogeneity caused by previous live capture should be accounted for in the population estimator. (JOURNAL OF WILDLIFE MANAGEMENT 72(3):589–595; 2008)     

Effect of Harvest on a Brown Bear Population in Alaska

There is a long and contentious history of brown bear (Ursus arctos) harvest management in Alaska, USA, the state that hosts the largest brown bear population in North America. In the mid-1990s, the Alaska Board of Game set the population objective for brown bears in Game Management Unit 13 A, located in interior southcentral Alaska, to be reduced by 50% to improve survival of moose (Alces alces) calves. The Board began further liberalizing brown bear harvest regulations for the unit beginning in regulatory year 1995, though adult females and their dependent offspring (i.e., cubs <2 yrs old) were protected. To evaluate progress toward this abundance objective, we captured and collared bears between 2006 and 2011 and conducted a capture-mark-resight density survey during summer 2011 for comparison to a similar baseline survey conducted in 1998. We report the results of the density survey and vital rates estimated from resight histories of collared bears and harvest information spanning from 1985 (10 years before establishment of the population objective) to 2012. There was a 25–40% reduction in abundance between 1998 and 2011. Population growth rates derived from density estimates and a matrix population projection model indicated that the population declined by 2.3–4.2% annually. We estimated harvest rates to be 8–15% annually, but harvest composition data indicated no changes in skull size, age distribution, or overall sex ratio. There was evidence of an increase in the proportion of older females in the harvest. Demographic analysis indicated high reproductive output and recruitment, potentially indicating a density-dependent compensatory response to reduced population size. Despite 13 years of harvest rates in excess of what had previously been considered to be sustainable for this population, the objective of reducing bear abundance by 50% had not been achieved as of 2011. The protection of females and dependent offspring in our study population appears to be a sufficient safeguard against a precipitous population decline while still permitting progress toward the population objective through high harvest on other segments of the population. © 2020 The Wildlife Society.     

The power of genetic monitoring for studying demography,ecology and genetics of a reintroduced brown bear population

Genetic monitoring has rarely been used for wildlife translocations despite the potential benefits this approach offers, compared to traditional field‐based methods. We applied genetic monitoring to the reintroduced brown bear population in northern Italy. From 2002 to 2008, 2781 hair and faecal samples collected noninvasively plus 12 samples obtained from captured or dead bears were used to follow the demographic and geographical expansion and changes in genetic composition. Individual genotypes were used to reconstruct the wild pedigree and revealed that the population increased rapidly, from nine founders to >27 individuals in 2008 (λ = 1.17–1.19). Spatial mapping of bear samples indicated that most bears were distributed in the region surrounding the translocation site; however, individual bears were found up to 163 km away. Genetic diversity in the population was high, with expected heterozygosity of 0.74–0.79 and allelic richness of 4.55–5.41. However, multi‐year genetic monitoring data showed that mortality rates were elevated, immigration did not occur, one dominant male sired all cubs born from 2002 to 2005, genetic diversity declined, relatedness increased, inbreeding occurred, and the effective population size was extremely small (Ne = 3.03, ecological method). The comprehensive information collected through genetic monitoring is critical for implementing future conservation plans for the brown bear population in the Italian Alps. This study provides a model for other reintroduction programmes by demonstrating how genetic monitoring can be implemented to uncover aspects of the demography, ecology and genetics of small and reintroduced populations that will advance our understanding of the processes influencing their viability, evolution, and successful restoration.     

DNA-Based Population Demographics of Black Bears in Coastal North Carolina and Virginia

ABSTRACT Noninvasive genetic sampling has become a popular method for obtaining population parameter estimates for black (Ursus americanus) and brown (U. arctos) bears. These estimates allow wildlife managers to develop appropriate management strategies for populations of concern. Black bear populations at Great Dismal Swamp (GDSNWR), Pocosin Lakes (PLNWR), and Alligator River (ARNWR) National Wildlife Refuges in coastal Virginia and North Carolina, USA, were perceived by refuge biologists to be at or above cultural and perhaps biological carrying capacity, but managers had no reliable abundance estimates upon which to base population management. We derived density estimates from 3,150 hair samples collected noninvasively at each of the 3 refuges, using 6–7 microsatellite markers to obtain multilocus genotypes for individual bears. We used Program MARK to calculate population estimates from capture histories at each refuge. We estimated densities using both traditional buffer strip methods and Program DENSITY. Estimated densities were some of the highest reported in the literature and ranged from 0.46 bears/km² at GDSNWR to 1.30 bears/km² at PLNWR. Sex ratios were male-biased at all refuges. Our estimates can be directly utilized by biologists to develop effective strategies for managing and maintaining bears at these refuges, and noninvasive methods may also be effective for monitoring bear populations over the long term.     

Characteristics of natural and anthropogenic mortality of an endangered brown bear population

Large carnivores’ far ranging habits and their requirements for wide areas often led them to move into unprotected lands, making them especially vulnerable to various human threats. Therefore, it is crucial to better understand their mortality characteristics and potential threats so to help guide conservation efforts. Brown bear is a protected species in Iran, however, knowledge on its population structure and causes of mortality are sparse. The main objective of this study was to understand the causes and spatio-temporal patterns of brown bear mortality in Iran. We carried out a systematic survey of internet media sources to answer (1) the mortality of which age and sex group is reported in the media; (2) what are the most common causes of mortality; (3) what are the temporal and spatial patterns of brown bear mortality?. Overall, we found 135 mortalities of brown bears in Iran from 2004 to 2019. Our findings showed that 84% of mortalities were related to anthropogenic causes and being shot (59%) was the most common cause followed by vehicle collisions (18.7%). Only 2% of reported mortalities were due to natural causes, and no information on the causes of mortality was available for 14%. We further found no differences in the sex distribution of bears killed, but adults (68%) were more commonly killed than subadults (22%); and age was unknown in 9% of mortalities. Most mortalities (75%) were reported in summer and autumn. We found that the number of bear mortality increased with increasing elevation, road density, proportion of forest cover, and that it was higher in areas with a higher proportion of protected areas (PA). However, most reported mortality cases were found outside of PAs. The main takeaway messages from our study are that the conservation of large carnivores in Iran must occur in co-existence with humans in a human-dominated landscape. It is also essential to obtain reliable data on population structure as well as more data on mortality rates and causes. We propose, among other conservation actions, the establishment of a central database for the systematic collection of data on human-carnivore conflicts as well as a compensation scheme for reimbursement of damages by large carnivores.     

Evolutionary and ecological traps for brown bears Ursus arctos in human‐modified landscapes

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Using a reference population yardstick to calibrate and compare genetic diversity reported in different studies: an example from the brown bear

In species with large geographic ranges, genetic diversity of different populations may be well studied, but differences in loci and sample sizes can make the results of different studies difficult to compare. Yet, such comparisons are important for assessing the status of populations of conservation concern. We propose a simple approach of using a single well-studied reference population as a ‘yardstick'' to calibrate results of different studies to the same scale, enabling comparisons. We use a well-studied large carnivore, the brown bear (Ursus arctos), as a case study to demonstrate the approach. As a reference population, we genotyped 513 brown bears from Slovenia using 20 polymorphic microsatellite loci. We used this data set to calibrate and compare heterozygosity and allelic richness for 30 brown bear populations from 10 different studies across the global distribution of the species. The simplicity of the reference population approach makes it useful for other species, enabling comparisons of genetic diversity estimates between previously incompatible studies and improving our understanding of how genetic diversity is distributed throughout a species range.     

Estimating population size and density of a low-density population of black bears in Rocky Mountain National Park, Colorado

Rocky Mountain National Park (RMNP) is home to a low-density black bear (Ursus americanus) population that exists at >2,400?m with a very limited growing season. A previous study (1984–1991) found bear densities among the lowest reported (1.37–1.52 bears/100?km²). Because of concerns of viability of this small population, we assessed population size and density of black bears from 2003 to 2006 to determine the current status of RMNP’s bear population. We used three approaches to estimate population size and density: (1) minimum number known, (2) occupancy modeling, and (3) catch per unit effort (CPUE). We used information from capture and remote-triggered cameras, as well as visitor information, to derive a minimum known population estimate of 20–24 individuals and a median density estimate of 1.35 bears/100?km². Bear occupancy was estimated at 0.46 (SE?=?0.11), with occupancy positively influenced by lodgepole pine stands, non-vegetated areas, and patch density but negatively influenced by mixed conifer stands. We combined the occupancy estimate with mean home-range size and overlap for bears in RMNP to derive a density estimate of 1.44 bears/100?km². We also related CPUE to density estimates for eight low-density black bear populations to estimate density in RMNP; this estimate (1.03 bears/100?km²) was comparable to the occupancy estimate and suggests that this approach may be useful for future population monitoring. The use of corroborative techniques for assessing population size of a low-density black bear population was effective and should be considered for similar low-density wildlife populations.     

Evidence of a large carnivore population recovery: Counting bears in Greece

Reliable population and density estimates are the cornerstone of effective conservation and management planning, as conservation priorities often arise in relation to population numbers. Despite increased public interest and costly conservation programs limited information on brown bear (Ursus arctos, Linnaeus, 1758) abundance and density in Greece exists. We carried out systematic non-invasive genetic sampling using hair traps on power poles, as part of a capture-mark-recapture study design in order to rigorously estimate abundance and density of the Pindos bear population in Greece. From 2007–2010 we identified 211 and estimated a mean of 182.3 individuals in four sampling areas; bear densities ranged from 10.0 to 54 bears/1000 km². These results indicate an important population recovery of this large carnivore in Greece in recent years; a conservative population estimate would place the population size in the entire country >450 individuals. Considering the results of the study and the increased negative interactions between humans and bears recorded currently in Greece, we suggest that systematic genetic monitoring using power poles should continue in order to collect the necessary information that will enable the definition of an effective Action Plan for the long-term conservation of this species.     

Identifying the risk regions of house break‐ins caused by Tibetan brown bears (Ursus arctos pruinosus) in the Sanjiangyuan region,China

Damage to homesteads by brown bears (Ursus arctos) has become commonplace in Asia, Europe, and the Americas. Science‐based solutions for preventing damages can contribute to the establishment of mechanisms that promote human–bear coexistence. We examined the spatial distribution patterns of house break‐ins by Tibetan brown bears (U. a. pruinosus) in Zhiduo County of the Sanjiangyuan region in China. Occurrence points of bear damage were collected from field surveys completed from 2017 to 2019. The maximum entropy (MaxEnt) model was then used to assess house break‐in risk. Circuit theory modeling was used to simulate risk diffusion paths based on the risk map generated from our MaxEnt model. The results showed that (a) the total risk area of house break‐ins caused by brown bears was 11,577.91 km², accounting for 29.85% of Zhiduo County, with most of the risk areas were distributed in Sanjiangyuan National Park, accounting for 58.31% of the total risk area; (b) regions of alpine meadow located in Sanjiangyuan National Park with a high human population density were associated with higher risk; (c) risk diffusion paths extended southeast to northwest, connecting the inside of Sanjiangyuan National Park to its outside border; and (d) eastern Suojia, southern Zhahe, eastern Duocai, and southern Jiajiboluo had more risk diffusion paths than other areas examined, indicating higher risk for brown bear break‐ins in these areas. Risk diffusion paths will need strong conservation management to facilitate migration and gene flow of brown bears and to alleviate bear damage, and implementation of compensation schemes may be necessary in risk areas to offset financial burdens. Our analytical methods can be applied to conflict reduction efforts and wildlife conservation planning across the Qinghai–Tibet Plateau.     

Distribution and genetic status of brown bears in FYR Macedonia: implications for conservation

Conservation and management of large carnivores is often hampered by the lack of information of basic biological parameters. This is particularly true for brown bears (Ursus arctos) in the Former Yugoslav Republic (FYR) of Macedonia. The bear population in this country is important, as it links bear populations of the central part of the Dinaric–Pindos population and the endangered population to the south in Greece. The aim of this study was to assess bear presence in FYR Macedonia and to provide the first evaluation of the genetic status of the species in this country. Bear presence was assessed through a questionnaire and sign surveys, while the genetic status of the species was evaluated through noninvasive genetic sampling from power poles and microsatellite analysis. The results of the study indicate the continuous and permanent presence of brown bears in FYR Macedonia from the border to Kosovo in the northwest, along the border to Albania and Greece in the south; bear presence around Mount Ko?uf in the south of the country was seasonal. High levels of genetic diversity were recorded, and it appears that this bear population is currently not threatened by low genetic variability. Cross-border movements of bears between FYR Macedonia and Greece were documented, indicating the presence of an interconnected population and outlining the necessity for a coordinated international approach in the monitoring and conservation of the species in southeastern Europe.     

Mandible size and shape in extant Ursidae (Carnivora,Mammalia): A tool for taxonomy and ecogeography

The family Ursidae is currently one of the taxonomic groups with the lowest number of species among Carnivora. Extant bear species exhibit broad ecological adaptations both at inter‐ and intraspecific level, and taxonomic issues within this family remain unresolved (i.e., the number of recognizable subspecies). Here, we investigate a sample of bear mandibles using two‐dimensional geometric morphometrics to better characterize bear taxonomy and evolution with a focus on one of the most widespread species: the brown bear (Ursus arctos). Our analyses confirm that both size and shape data are useful continuous characters that discriminate with very high percentage of accuracy extant bears. We also identify two very distinct mandibular morphologies in the subspecies Ursus actos isabellinus and Ursus arctos marsicanus. These taxa exhibit a high degree of morphological differentiation possibly as a result of a long process of isolation. Ecogeographical variation occurs among bear mandibles with climate impacting the diversification of the whole family.     

Alaskan brown bears (Ursus arctos) aggregate and display fidelity to foraging neighborhoods while preying on Pacific salmon along small streams

The interaction between brown bears (Ursus arctos) and Pacific salmon (Oncorhynchus spp.) is important to the population dynamics of both species and a celebrated example of consumer‐mediated nutrient transport. Yet, much of the site‐specific information we have about the bears in this relationship comes from observations at a few highly visible but unrepresentative locations and a small number of radio‐telemetry studies. Consequently, our understanding of brown bear abundance and behavior at more cryptic locations where they commonly feed on salmon, including small spawning streams, remains limited. We employed a noninvasive genetic approach (barbed wire hair snares) over four summers (2012–2015) to document patterns of brown bear abundance and movement among six spawning streams for sockeye salmon, O. nerka, in southwestern Alaska. The streams were grouped into two trios on opposite sides of Lake Aleknagik. Thus, we predicted that most bears would forage within only one trio during the spawning season because of the energetic costs associated with swimming between them or traveling around the lake and show fidelity to particular trios across years because of the benefits of familiarity with local salmon dynamics and stream characteristics. Huggins closed‐capture models based on encounter histories from genotyped hair samples revealed that as many as 41 individuals visited single streams during the annual 6‐week sampling season. Bears also moved freely among trios of streams but rarely moved between these putative foraging neighborhoods, either during or between years. By implication, even small salmon spawning streams can serve as important resources for brown bears, and consistent use of stream neighborhoods by certain bears may play an important role in spatially structuring coastal bear populations. Our findings also underscore the efficacy of noninvasive hair snagging and genetic analysis for examining bear abundance and movements at relatively fine spatial and temporal scales.     

Challenges of DNA-Based Mark-Recapture Studies of American Black Bears

Abstract: We explored whether genetic sampling would be feasible to provide a region-wide population estimate for American black bears (Ursus americanus) in the southern Appalachians, USA. Specifically, we determined whether adequate capture probabilities (p > 0.20) and population estimates with a low coefficient of variation (CV < 20%) could be achieved given typical agency budget and personnel constraints. We extracted DNA from hair collected from baited barbed-wire enclosures sampled over a 10-week period on 2 study areas: a high-density black bear population in a portion of Great Smoky Mountains National Park and a lower density population on National Forest lands in North Carolina, South Carolina, and Georgia. We identified individual bears by their unique genotypes obtained from 9 microsatellite loci. We sampled 129 and 60 different bears in the National Park and National Forest study areas, respectively, and applied closed mark-recapture models to estimate population abundance. Capture probabilities and precision of the population estimates were acceptable only for sampling scenarios for which we pooled weekly sampling periods. We detected capture heterogeneity biases, probably because of inadequate spatial coverage by the hair-trapping grid. The logistical challenges of establishing and checking a sufficiently high density of hair traps make DNA-based estimates of black bears impractical for the southern Appalachian region. Alternatives are to estimate population size for smaller areas, estimate population growth rates or survival using mark-recapture methods, or use independent marking and recapturing techniques to reduce capture heterogeneity.