Ursus Americanus Research Articles

Survival of rehabilitated yearling American black bears

Scant information regarding the fate of rehabilitated American black bears (Ursus americanus) postrelease exists in the literature. We estimated survival of 28 rehabilitated bears that were released between 2015 and 2018 in North Carolina, USA, and investigated what biological, landscape, and behavioral factors influenced their survival in their first year postrelease. Sixty-one percent of the bears died within 1 year and 65% of the mortalities were from legal hunter harvest. Bear survival declined rapidly with increasing road density. Few mortalities were attributed to vehicular incidents; therefore, road density likely acts as proxy to hunting accessibility, especially in rural areas. Home ranges of bears in our study included 0–11% development and we estimated our bears had a 90% survival rate within their first year postrelease if their home range included 6–11% of developed land. In urban areas, ordinances and small parcels tend to restrict the opportunity for hunting, which may create a refugia for some black bears. Our results also indicate that female rehabilitated bears may be more susceptible to hunting pressures than are wild females. Release weight had a positive effect on survival; heavier bears were likely less attracted to anthropogenic food sources (e.g., crops, bird feeders) that would have made them susceptible to hunters compared with more reliable, natural food sources. Individuals that moved slightly more tortuous paths than average in our study had a lower survival probability, likely from remaining in the same area. We recommend that managers select release sites for bears that limit harvest via accessible roads. We also recommend ensuring 1.25–1.5-year-old bears are ≥71 kg at release to enhance survival probability. Our results add to the growing body of bear rehabilitation research and can inform programs in which rehabilitation is critical to species restoration efforts.

What drives spatially varying ecological relationships in a wide‐ranging species?

AbstractAimDecades of research on species distributions has revealed geographic variation in species‐environment relationships for a given species. That is, the way a species uses the local environment varies across geographic space. However, the drivers underlying this variation are contested and still largely unexplored. Niche traits that are conserved should reflect the evolutionary history of a species whereas more flexible ecological traits could vary at finer scales, reflecting local adaptation.LocationNorth America.MethodsWe used mammal observations during a 5‐year period from the iNaturalist biodiversity database and a local ensemble modelling approach to explore spatial variation in American black bear (Ursus americanus) relationships with eight ecological correlates. We tested four biologically driven hypotheses to explain the patterns of local adaptation. We evaluated non‐stationarity in ecological relationships using a Stationarity Index and tested predictive performance using an independent, national‐level animal occurrence data set.ResultsWe documented considerable spatial non‐stationarity in all eight environmental relationships, with the greatest spatial variation occurring in bear's relationship to climatic factors. Notably, the greatest variation in environmental relationships tended to occur along the current boundaries of the species' range, potentially representing the ecological limits to the species geographic range. We additionally documented that spatial variation in relationships with land cover and anthropogenic factors were best explained by niche conservatism at the subspecies level, whereas climatic relationships were better explained by local adaptation.Main ConclusionsBased on these results, we propose that the current distribution of American black bear is determined by an evolutionary legacy of habitat relationships unique to each subspecies combined with more fine‐scale local adaptation to climatic conditions. This result suggests that black bears should be adaptable to climatic changes over the 21st century and that management of habitat and human‐bear relationships could be considered at the subspecies level.

White-tailed deer exploit temporal refuge from multi-predator and human risks on roads.

Although most prey have multiple predator species, few studies have quantified how prey respond to the temporal niches of multiple predators which pose different levels of danger. For example, intraspecific variation in diel activity allows white‐tailed deer (Odocoileus virginianus) to reduce fawn activity overlap with coyotes (Canis latrans) but finding safe times of day may be more difficult for fawns in a multi‐predator context. We hypothesized that within a multi‐predator system, deer would allocate antipredation behavior optimally based on combined mortality risk from multiple sources, which would vary depending on fawn presence. We measured cause‐specific mortality of 777 adult (>1‐year‐old) and juvenile (1–4‐month‐old) deer and used 300 remote cameras to estimate the activity of deer, humans, and predators including American black bears (Ursus americanus), bobcats (Lynx rufus), coyotes, and wolves (Canis lupus). Predation and vehicle collisions accounted for 5.3 times greater mortality in juveniles (16% mortality from bears, coyotes, bobcats, wolves, and vehicles) compared with adults (3% mortality from coyotes, wolves, and vehicles). Deer nursery groups (i.e., ≥1 fawn present) were more diurnal than adult deer without fawns, causing fawns to have 24–38% less overlap with carnivores and 39% greater overlap with humans. Supporting our hypothesis, deer nursery groups appeared to optimize diel activity to minimize combined mortality risk. Temporal refuge for fawns was likely the result of carnivores avoiding humans, simplifying diel risk of five species into a trade‐off between diurnal humans and nocturnal carnivores. Functional redundancy among multiple predators with shared behaviors may partially explain why white‐tailed deer fawn predation rates are often similar among single‐ and multi‐predator systems.

Dietary niche separation of three Late Pleistocene bear species from Vancouver Island, on the Pacific Northwest Coast of North America

AbstractCompetition between taxa related to climate changes has been proposed as a possible factor in Pleistocene megafaunal extinctions, and here we present isotope evidence of the diets of three co‐existing bear species [black bear (Ursus americanus), brown bear (Ursus arctos), and the now extinct short‐faced bear (Arctodus simus)] from a locale in western North America dating to the Late (Terminal) Pleistocene (~14.5–11.7 ka). The three bear species were found at several sites on Vancouver Island, on the western coast of Canada. To examine the chronological overlap and niche partitioning between these species of bear, we used direct radiocarbon dating, stable isotope analysis and ZooMS proteomic identification methods. Here we present new radiocarbon evidence from Terminal Pleistocene U. americanus, U. arctos and A. simus from several sites on the island, along with both bulk collagen and compound‐specific isotope data for these species. Radiocarbon dates confirm the chronological overlap of Arctodus and both Ursus species in the montane regions of the island at the end of the Pleistocene. Stable isotope data reveal niche differentiation between these species, with U. americanus occupying a distinctly lower trophic position than the other two taxa.

Genetic diversity and population history of the Japanese black bear (Ursus thibetanus japonicus) based on the genome‐wide analyses

AbstractThe Japanese black bear (Ursus thibetanus japonicus) is a subspecies of the Asian black bear endemic to Mainland Japan. It has been reported that the extant Japanese bear population is genetically differentiated into several geographically restricted clusters with an estimated divergence time of 100,000–500,000 years ago. The ancestral population of the Japanese black bear migrated from the continent to the Japanese archipelago in the Pleistocene, and no interaction between continental and Japanese bear populations after their migration has been speculated. However, most of the previous studies are based only on mitochondrial DNA. Here, we sequenced the genome of a Japanese black bear and compared it with that of other Ursus individuals to evaluate the genetic status of this subspecies. We suggest that the Japanese black bear population is genetically almost uniform and has been structured only in recent 30,000 years. This inconsistency between mitochondria and nuclear DNA may be explained by the female philopatry and male‐mediated gene flow of this species. We also suggest ancestral admixture between the Japanese black bear and the Ussuri black bear (Ursus thibetanus ussuricus), implying a complex history of inter‐subspecies interactions of the Japanese black bears. Genomic evidence of ancient admixture between the Asian black bear and the American black bear (Ursus americanus) sheds new light on the population history of the Asian black bears. The genetic diversity of the Japanese black bears is remarkably lower compared to thaother bear populations, and conservation of this subspecies is an urgent issue.

Explaining detection heterogeneity with finite mixture and non-Euclidean movement in spatially explicit capture-recapture models.

Landscape structure affects animal movement. Differences between landscapes may induce heterogeneity in home range size and movement rates among individuals within a population. These types of heterogeneity can cause bias when estimating population size or density and are seldom considered during analyses. Individual heterogeneity, attributable to unknown or unobserved covariates, is often modelled using latent mixture distributions, but these are demanding of data, and abundance estimates are sensitive to the parameters of the mixture distribution. A recent extension of spatially explicit capture-recapture models allows landscape structure to be modelled explicitly by incorporating landscape connectivity using non-Euclidean least-cost paths, improving inference, especially in highly structured (riparian & mountainous) landscapes. Our objective was to investigate whether these novel models could improve inference about black bear (Ursus americanus) density. We fit spatially explicit capture-recapture models with standard and complex structures to black bear data from 51 separate study areas. We found that non-Euclidean models were supported in over half of our study areas. Associated density estimates were higher and less precise than those from simple models and only slightly more precise than those from finite mixture models. Estimates were sensitive to the scale (pixel resolution) at which least-cost paths were calculated, but there was no consistent pattern across covariates or resolutions. Our results indicate that negative bias associated with ignoring heterogeneity is potentially severe. However, the most popular method for dealing with this heterogeneity (finite mixtures) yielded potentially unreliable point estimates of abundance that may not be comparable across surveys, even in data sets with 136–350 total detections, 3–5 detections per individual, 97–283 recaptures, and 80–254 spatial recaptures. In these same study areas with high sample sizes, we expected that landscape features would not severely constrain animal movements and modelling non-Euclidian distance would not consistently improve inference. Our results suggest caution in applying non-Euclidean SCR models when there is no clear landscape covariate that is known to strongly influence the movement of the focal species, and in applying finite mixture models except when abundant data are available.

Rub tree use and selection by American black bears and grizzly bears in northern Yellowstone National Park

Several of the world's bear species exhibit tree-rubbing behavior, which is thought to be a form of scent-marking communication. Many aspects of this behavior remain unexplored, including differences in rub tree selection between sympatric bear species. We compiled rub tree data collected on Yellowstone National Park's Northern Range (USA) and compared rub tree selection of sympatric American black bears (Ursus americanus) and grizzly bears (U. arctos) at local and landscape scales. During 2017 and 2018, we identified 217 rub trees and detected black bears at 117 rub trees and grizzly bears at 18 rub trees, based on genetic analysis of collected hair samples. Rub trees generally were located in areas with gentle slopes and close to existing animal trails. Trees selected by black bears were typically in forested areas, whereas trees selected by grizzly bears were in forested and more open areas. Use of rub trees varied seasonally and between sexes for black bears, but seasonal data were inconclusive for grizzly bears. Black bears showed preferences for certain tree species for rubbing, but we did not find evidence that rub tree selection by grizzly bears differed among tree species. Both bear species selected trees that lacked branches on the lower portions of tree trunks and the maximum rub height was consistent with the body length of the bear species that used the tree. Although the sample size for grizzly bears was small, identifying the species and sex of bears based on genetic analysis enhanced interpretation of rub tree use and selection by bears. Scent-marking by black bears and grizzly bears on similar rub objects in well-traversed areas likely serves to enhance communication within and between the 2 species.

Human impacts on mammals in and around a protected area before, during, and after COVID-19 lockdowns.

The dual mandate for many protected areas (PAs) to simultaneously promote recreation and conserve biodiversity may be hampered by negative effects of recreation on wildlife. However, reports of these effects are not consistent, presenting a knowledge gap that hinders evidence‐based decision‐making. We used camera traps to monitor human activity and terrestrial mammals in Golden Ears Provincial Park and the adjacent University of British Columbia Malcolm Knapp Research Forest near Vancouver, Canada, with the objective of discerning relative effects of various forms of recreation on cougars (Puma concolor), black bears (Ursus americanus), black‐tailed deer (Odocoileus hemionus), snowshoe hares (Lepus americanus), coyotes (Canis latrans), and bobcats (Lynx rufus). Additionally, public closures of the study area associated with the COVD‐19 pandemic offered an unprecedented period of human‐exclusion through which to explore these effects. Using Bayesian generalized mixed‐effects models, we detected negative effects of hikers (mean posterior estimate = −0.58, 95% credible interval [CI] −1.09 to −0.12) on weekly bobcat habitat use and negative effects of motorized vehicles (estimate = −0.28, 95% CI −0.61 to −0.05) on weekly black bear habitat use. We also found increased cougar detection rates in the PA during the COVID‐19 closure (estimate = 0.007, 95% CI 0.005 to 0.009), but decreased cougar detection rates (estimate = −0.006, 95% CI −0.009 to −0.003) and increased black‐tailed deer detection rates (estimate = 0.014, 95% CI 0.002 to 0.026) upon reopening of the PA. Our results emphasize that effects of human activity on wildlife habitat use and movement may be species‐ and/or activity‐dependent, and that camera traps can be an invaluable tool for monitoring both wildlife and human activity, collecting data even when public access is barred. Further, we encourage PA managers seeking to promote both biodiversity conservation and recreation to explicitly assess trade‐offs between these two goals in their PAs.

The influence of human disturbance on Pacific salmon (Oncorhynchus spp.) in the diet of American black bears (Ursus americanus) in two areas of coastal British Columbia, Canada

Recent studies have highlighted the importance of salmon (genus Oncorhynchus Suckley, 1861) in the diet of bears, and of bears as consumers and key agents supporting the transport of salmon-derived nutrients to riparian ecosystems. Salmon abundance and human disturbance are known influences on bear ecology and behaviour, though few studies have quantified shifts in bear diet due to these effects. We used stable isotope analysis to investigate how salmon escapement and human presence influenced the proportion of salmon in the diet of American black bears ( Ursus americanus Pallas, 1780) in two locations in coastal British Columbia, Canada. We found that salmon constituted a small proportion of black bear diet across sexes and ecosystems, while bears appeared to gain a similar amount of energy and lean mass from terrestrial sources. Salmon consumption was not related to the total annual abundance of salmon in a watershed but was significantly lower in large streams with regular human presence, suggesting that human disturbance can cause a dietary shift in bears that could have important consequences to their fitness. We also observed that the isotopic signatures of key bear foods did not vary between foliage and fruit, simplifying data collection for future isotopic studies on bear diet.

Using psychometrics to characterize the cognitive antecedents of tolerance for black bears

ABSTRACT Tolerance for wildlife can be informed by a person’s beliefs, attitudes, norms, or other characteristics. Although theoretical papers emphasize the interrelations of these multiple antecedents of wildlife tolerance, empirical studies have not tested them using a rigorous scale development process. We used psychometrics to characterize the cognitive antecedents of tolerance toward black bears (Ursus americanus). Proposed scale items were tested via web-hosted questionnaire (n = 240) and refined into 29 items representing five antecedent dimensions of tolerance for black bears. We then administered these items to a different sample of recreational trail users in western Oregon (n = 210). Second-order confirmatory factor analysis confirmed a 19-item measure representing four distinct yet related antecedent dimensions of tolerance: antipathy, connection, lethal control (damage), and lethal control (danger to self, pets, and economics). These dimensions help better explain why people may be more or less tolerant toward black bears and, potentially, other wildlife.

The scavenger spyglass: how recruiting hunters to watch carrion boosts wildlife research

AbstractHunters support scavengers with seasonal pulses of carrion. If those hunters also deploy remote cameras at kill sites, they could simultaneously contribute data to wildlife research while gaining first‐hand knowledge of scavenger ecology. In 2018–2020, we recruited hunters to monitor carcasses and offal with remote cameras across western Montana, USA. We increased our sampling effort by also setting up cameras following successful elk (Cervus canadensis) hunts at a private ranch. Cameras recorded 19 scavenger species. Golden eagles (Aquila chrysaetos) appeared at 55% of sites, and 3 individuals wore auxiliary markers, demonstrating how hunters can augment efforts to detect tagged wildlife. Cameras also documented elusive predators (e.g., wolves [Canis lupus]) and a seasonality of scavenging among American black bears (Ursus americanus). At 42% of the sites, ≥1 cervid investigated the carrion within 1 m, a behavior that may transmit the prions associated with chronic wasting disease. Hunters are willing and competent citizen scientists that can help generate wildlife observations at a broad spatial scale.

Exposure of American black bears to various pathogens in Wisconsin

We compared location, sex, and season of 97 American black bears (Ursus americanus) captured and sampled from March 2003 to March 2006 near Lakewood and Hiles, Wisconsin, USA, relative to exposure to toxoplasmosis, canine distemper virus (CDV), eastern equine encephalitis virus, Venezuelan equine encephalitis, St. Louis encephalitis, canine parvovirus, and tularemia. A large percentage of black bears in both locations had antibodies against CDV and toxoplasmosis (41.1–56.9% and 41.8–67.4%, respectively). Exposure of bears to CDV was significantly higher in those sampled during the winter. There was strong evidence that exposure to toxoplasmosis was significantly greater in bears near Hiles than those near Lakewood. There was weak evidence that exposure to tularemia was different in bears near Hiles than those near Lakewood. There was also weak evidence that exposure to tularemia was different in females than males. We found only a small percentage of black bears with detectable antibodies against eastern equine encephalitis virus, Venezuelan equine encephalitis, and St. Louis encephalitis (2.2–3.8%, 2.2–4.3%, and 0–2.8%, respectively) at both locations. Our results are similar to those of other studies, suggesting that exposure to toxoplasmosis and CDV may be prevalent among black bears across North America. We also draw attention to the need for validation studies for serological tests in black bears, so that accurate measures of sensitivity and specificity of these tests may be provided.

Efficacy and ethics of intensive predator management to save endangered caribou

AbstractLethal population control has a history of application to wildlife management and conservation. There is debate about the efficacy of the practice, but more controversial is the ethical justification and methods of killing one species in favor of another. This is the situation facing the conservation of woodland caribou (Rangifer tarandus caribou) in Canada. Across multiple jurisdictions, large numbers of wolves (Canis lupus), and to a lesser extent bears (Ursus americanus) and coyotes (C. latrans), are killed through trapping, poisoning or aerial shooting to halt or reverse continued declines of woodland caribou. While there is evidence to support the effectiveness of predator management as a stop‐gap solution, questions remain about the extent to which this activity can make a meaningful contribution to long‐term recovery. Also, there are myriad ethical objections to the lethal removal of predators, even if that activity is in the name of conservation. Debates about predator management, just one of numerous invasive actions for maintaining caribou, are made even more complex by the conflation of ethics and efficacy. Ultimately, long‐term solutions for the recovery of caribou require governments to stop delaying difficult decisions that address the real causes of population decline, habitat change.

Precision and bias of spatial capture-recapture estimates: A multi-site, multi-year Utah black bear case study.

Spatial capture–recapture (SCR) models are powerful analytical tools that have become the standard for estimating abundance and density of wild animal populations. When sampling populations to implement SCR, the number of unique individuals detected, total recaptures, and unique spatial relocations can be highly variable. These sample sizes influence the precision and accuracy of model parameter estimates. Testing the performance of SCR models with sparse empirical data sets typical of low‐density, wide‐ranging species can inform the threshold at which a more integrated modeling approach with additional data sources or additional years of monitoring may be required to achieve reliable, precise parameter estimates. Using a multi‐site, multi‐year Utah black bear (Ursus americanus) capture–recapture data set, we evaluated factors influencing the uncertainty of SCR structural parameter estimates, specifically density, detection, and the spatial scale parameter, sigma. We also provided some of the first SCR density estimates for Utah black bear populations, which ranged from 3.85 to 74.33 bears/100 km2. Increasing total detections decreased the uncertainty of density estimates, whereas an increasing number of total recaptures and individuals with recaptures decreased the uncertainty of detection and sigma estimates, respectively. In most cases, multiple years of data were required for precise density estimates (<0.2 coefficient of variation [CV]). Across study areas there was an average decline in CV of 0.07 with the addition of another year of data. One sampled population with very high estimated bear density had an atypically low number of spatial recaptures relative to total recaptures, apparently inflating density estimates. A complementary simulation study used to assess estimate bias suggested that when <30% of recaptured individuals were spatially recaptured, density estimates were unreliable and ranged widely, in some cases to >3 times the simulated density. Additional research could evaluate these requirements for other density scenarios. Large numbers of individuals detected, numbers of spatial recaptures, and precision alone may not be sufficient indicators of parameter estimate reliability. We provide an evaluation of simple summary statistics of capture–recapture data sets that can provide an early signal of the need to alter sampling design or collect auxiliary data before model implementation to improve estimate precision and accuracy.

CO-OCCURRENCE OF FOUR ENDANGERED MAMMALS IN THE MEXICO–UNITED STATES BORDERLANDS: JAGUAR (PANTHERA ONCA), OCELOT (LEOPARDUS PARDALIS), BEAVER (CASTOR CANADENSIS) AND BLACK BEAR (URSUS AMERICANUS)

The unique biogeography of the Madrean Archipelago facilitates the cohabitation of species that otherwise rarely overlap in their spatial distributions. As part of a long-term study at Cuenca Los Ojos, Sonora, we deployed 25 cameras along washes within the property from October 2018 to April 2019, adding to the camera-trap information collected at the site since 2016. Ocelot (Leopardus pardalis) was recorded once in 2018, twice in 2016 and 2020, but not during the 2018–2019 study period. Black bear (Ursus americanus) was recorded regularly throughout the season with several images including cubs. One picture and several signs of beaver (Castor canadensis) were discovered in 2018 and 2019. Lastly, the first record of jaguar (Panthera onca) in Cuenca Los Ojos was recorded in February and March 2019 at four different sites. All species are considered endangered in Mexico and species of conservation concern in the United States and were recorded within 5 km south of the USA–Mexico border wall. Our addition of the new ocelot sighting in this region marks the only known location with records of all four species overlapping in space and time despite historical distribution ranges of black bears, jaguars, and beavers overlapping. Given the current border wall construction and highway development, which both affect the natural connectivity of the region, it will be necessary to incorporate the presence of the four species in all future mitigation efforts.

Evaluating how management policies affect red wolf mortality and disappearance.

Poaching is the major cause of death for large carnivores in several regions, contributing to their global endangerment. The traditional hypothesis used in wildlife management (killing for tolerance) suggests reducing protections for a species will decrease poaching. However, recent studies suggest reducing protections will instead increase poaching (facilitated illegal killing) and its concealment (facilitated cryptic poaching). Here, we build survival and competing risk models for mortality and disappearances of adult collared red wolves (Canis rufus) released in North Carolina, USA from 1987 to 2020 (n = 526). We evaluated how changes in federal and state policies protecting red wolves influenced the hazard and incidence of mortality and disappearance. We observed substantial increases in the hazard and incidence of red wolf reported poaching, and smaller increases in disappearances, during periods of reduced federal and state protections (including liberalizing hunting of coyotes, C. latrans); white-tailed deer (Odocoileus virginianus) and American black bear (Ursus americanus) hunting seasons; and management phases. Observed increases in hazard (85–256%) and incidence of reported poaching (56–243%) support the ‘facilitated illegal killing' hypothesis. We suggest improving protective policies intended to conserve endangered species generally and large carnivores in particular, to mitigate environmental crimes and generally improve the protection of wild animals.

Conserved and Taxon-Specific Patterns of Phenotypic Modularity in the Mammalian Dentition.

SynopsisPrevious genotype:phenotype mapping of the mouse and primate dentition revealed the presence of pre- and post-canine modules in mice and anthropoid primates, as well as molar and premolar submodules in anthropoid primates. We estimated phenotypic correlation matrices for species that sample broadly across Mammalia to test the hypothesis that these modules exist across a broader range of taxa and thereby represent a conserved mammalian trait. We calculated phenotypic correlation matrices from linear dental measurements of 419 individual specimens representing 5 species from 4 mammalian orders: Artiodactyla (Odocoileus hemionus), Carnivora (Canis latrans and Ursus americanus), Didelphimorphia (Didelphis virginiana), and Primates (Colobus guereza). Our results based on hierarchical clustering indicate a generally higher correlation within incisors and among post-canine teeth. However, the post-canine phenotypic correlation matrices do not consistently exhibit the premolar and molar submodularity observed in anthropoid primates. Additionally, we find evidence of sex differences in the Odocoileus phenotypic correlation matrices: Males of this species exhibit overall higher inter-trait correlations compared to females. Our overall findings support the interpretation that incisors and post-canine dentition represent different phenotypic modules, and that this architecture may be a conserved trait for mammals.

PATTERNS OF WILDLIFE ACTIVITY AND PREDATOR-PREY DYNAMICS IN A HIGHLY TOURISTED AREA

Tourist activity in natural areas may impact species' behavior and ecology as well as predator-prey dynamics. Although previous research has demonstrated effects of human disturbance on wildlife communities, only a limited number of studies have focused on small mammals and coyote predator-prey systems. To generate an overview of human impacts on these wildlife communities, we analyzed camera trap data from a human-disturbed site at Lake Tahoe, California. To compare species' activity patterns in relation to distances from human-disturbed areas, we used single-species occupancy models, estimations of species' temporal activity overlaps, and the time between detections of different species at camera sites. We found that in general black bears (Ursus americanus) avoided areas of high human disturbance, whereas coyotes (Canis latrans), rodents, and lagomorphs favored them. However, rodents and lagomorphs also avoided areas with high coyote detections, indicating that rodents and lagomorphs mostly used human-disturbed areas that were not highly frequented by coyotes. Additionally, all aforementioned species avoided humans temporally and this avoidance increased in closer proximity to human-disturbed areas. These findings indicate that while some species frequented human-disturbed areas more than others, all species studied exhibited greater temporal avoidance of humans when closer to areas of higher human activity. Our results also indicate that rodents' and lagomorphs' activity patterns overlapped more with coyotes' activity patterns closer to human-disturbed areas and rodents and lagomorphs avoided coyotes less in these areas. The greater overlap of the species' activity patterns suggests that there is likely more interaction between coyotes and their prey closer to areas of high human activity. The changes in the behavior and ecology of wildlife communities closer to human-disturbed areas reported here emphasize how proximity to human-disturbed areas may influence both predator and prey demographics.

Remotely triggered door and real‐time monitoring for bear cage traps

AbstractWe modified the bear cage trap with a low‐cost remotely triggered trap door and fitted the trap with a motion activated camera that relayed bear captures to researchers in real time. We built 4 modified bear cage traps and used them to capture free‐ranging American black bears (Ursus americanus) during summer 2020 on MPG Ranch in western Montana, USA. Lacking data on bear confinement time in traps from previous studies, we compared the amount of time that bears were confined in our modified traps with estimated confinement time had the same bears in our study been captured in traditional traps that were physically checked once daily at 0900, once daily at 1200, or twice daily at 0900 and 1600. We captured bears 30 times during 195 trap nights. The camera system relayed photos of all captures in real time and the remotely triggered door release was 100% successful. When we evaluated all bear captures and recaptures (n = 30), mean bear confinement time in our modified traps (4.92 hrs) was significantly lower than estimated mean confinement time had the same bears been captured in traditional traps that were checked once daily at 0900 (14.95 hrs), once daily at 1200 (10.73 hrs), or twice daily at 0900 and 1600 (7.01 hrs). For bears that were recaptured during regular trap monitoring hours (0700–1800) and remotely released without immobilization (n = 12), mean confinement time in our modified traps was &lt;1 hr. By remotely monitoring traps, we saved an estimated US $6,580 or $13,624 in gas and staff hours during 3 months of trapping, had we physically checked traps once or twice daily, respectively. Our modified traps minimized animal confinement time, eliminated unnecessary animal immobilizations, and helped us maximize time and resource efficiencies. Our findings are relevant to bear research and management, and the technology we used can be adapted for trapping other wildlife species.

Integrating video and genetic data to estimate annual age‐structured apparent survival of American black bears

AbstractCamera or genetic data are increasingly used to estimate wildlife abundance and density. We integrated video camera data with genetic data over 7 years to estimate annual age‐structured apparent survival of American black bears (Ursus americanus). We identified 70 individuals through meticulous scrutiny of 7531 video captures, cross‐referenced with 721 genetic captures from hair samples concurrently collected from stations in view of cameras. We used the Cormack–Jolly–Seber model in Program Mark to estimate annual age‐structured apparent survival for yearling males, yearling females, 2+ year‐old males, and 2+ year‐old females. We manually calculated cub survival. We compared parameter estimates based on combined video and genetic data with those based on only genetic data. Combining video and genetic data provided a means to test video‐based identification accuracy, which was highest for females (97%–100%). Annual apparent survival was highest for yearling females (φ = 0.92, SE = 0.07), followed by 2+ year‐old females (φ = 0.88, SE = 0.05), 2+ year‐old males (φ = 0.84, SE = 0.06), and yearling males (φ = 0.80, SE = 0.14). Annual cub survival (φ = 0.86, SE = 0.07) was likely biased because we could not account for mortality that occurred in‐den through early spring. Annual apparent survival and recapture probabilities derived from only genetic data were lower than those derived from combined video and genetic data. Our finding that noninvasive data can be used to estimate annual age‐structured apparent survival of a species with relatively indistinct traits is broadly relevant to wildlife research and conservation.