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In human‐dominated landscapes, rebounding bear populations share space with people, which may lead to bear–human conflicts and, consequently, a decrease in acceptance and an increase in bear mortality linked to human causes. Previous analyses of brown bear (Ursus arctos) movement data have shown that bears adopt a security‐food trade‐off strategy in response to variable human‐related risk. However, brown bear flexibility to cope with these risky situations may be reduced when resting, mating or stocking fat in preparation for hibernation. In this study, we measured the multi‐scale spatial response of brown bears to human‐related risk and food resource distribution in a highly heterogeneous human‐dominated landscape. We examined habitat selection both within the population range ('second‐order' selection) and at bedding site locations ('third‐order') for GPS‐tagged brown bears of a recently reintroduced population in the Italian Alps. We identified resting locations by field‐validated spatio‐temporal cluster analysis of telemetry locations. We mapped food availability and distribution using dynamic geographic layers of fruiting wild berries, and human‐related risk using human mobility data (Strava‐based Cumulated Outdoor activity Index). Brown bears appeared to compromise their need for food resources for avoidance of anthropogenic disturbance when selecting home ranges, as they utilized areas richer in wild berries less when human use of outdoor tracks was higher. Furthermore, selection of resting site locations strongly depended on the avoidance of human‐related risk only, with less frequented, more concealed and inaccessible sites being selected. We conclude that humans compete for space with bears beyond their infrastructural impact, that is, by actively occupying key areas for bear survival, thereby potentially restricting the bears' realized niche. We propose mitigating actions to promote bear–human coexistence by selectively restricting human access to key areas during sensitive annual physiological phases for bear survival. [ABSTRACT FROM AUTHOR]

Simple Summary: Fragmented habitats threaten animals by reducing genetic diversity. It is essential to understand the genetic composition and movement patterns of brown bears for effective conservation strategies and fostering coexistence with humans. This study analyzed 214 hair samples collected non-invasively from brown bears in the Trikala-Meteora area of Central Greece, revealing the genetic status and demographics of a local sub-population. Although the broader Central and South Pindos regions have not been examined in over ten years, findings indicate high genetic diversity, no signs of inbreeding, and an estimated effective population size of 99, suggesting a healthy conservation status. Additionally, a natural corridor facilitating bear movement between the western and eastern sections of the study area supports the population's sustainability. These results will aid in future conservation efforts aimed at maintaining natural corridors for brown bear habitats in Greece. Habitat fragmentation poses a significant threat to the existence and reproduction of large carnivores, such as brown bears, as it affects the genetic connectivity of populations and, consequently, their long-term viability. Understanding the genetic makeup and dispersal patterns in areas where brown bears live is crucial for developing effective conservation plans and promoting human-brown bear coexistence. In this study, 214 hair samples were collected non-invasively from brown bears and were genetically analyzed using fifteen specific microsatellite loci to shed light on the genetic status and demography of a sub-population residing in Central Greece (Trikala-Meteora area). The broader Central and South Pindos regions have not been studied for over a decade; however, high levels of genetic diversity, a lack of heterozygosity deficiency, and no signs of inbreeding, along with an estimated effective population size (Ne = 99), confirm the good conservation status of this sub-population. Moreover, the existence of a natural and apparently functional corridor in Central Pindos was demonstrated by bear movements between the western and eastern parts of the project area, enhancing the sustainability of the population. These findings will contribute to future efforts to conserve natural corridors that enable functional connectivity among large areas of brown bear territories in Greece. [ABSTRACT FROM AUTHOR]

Survival of juvenile ungulates represents an important demographic parameter that influences population dynamics within ecosystems. In many ecological systems, the mortality of juvenile ungulates is influenced by various factors, including predation by large carnivores, human hunting activities and weather. While wolves Canis lupus are known to prey on moose Alces alces throughout all seasons, brown bears Ursus arctos primarily engage in predation during early summer, while human harvest primarily occurs in autumn and early winter. Hence, understanding the impacts of predation, harvest, and weather on the survival of juvenile moose is crucial for adaptive population management and the determination of sustainable harvest rates. To investigate the summer and autumn–winter survival of moose calves in relation to carnivore occurrence (wolf presence and bear density), summer habitat productivity, winter severity, human harvest, and migratory behaviour (migratory versus resident), we analysed data collected from 39 GPS‐collared female moose in south‐central Scandinavia. Our findings revealed significant interannual variation in summer survival rates, with areas with relatively higher bear densities exhibiting calf mortality rates twice as high as those in regions with low bear density. During the autumn–winter period, calf survival was lowest in the presence of wolves and deep snow, and it exhibited a negative correlation with the proportion of clearcuts and young forests within the mother's home range. Additionally, calf survival was negatively correlated with the risk of human hunting, and calves of stationary females displayed ten times higher survival rates compared to migratory individuals. Our study provides valuable insights into the survival of moose calves coexisting with two large carnivores and humans. Improving our understanding of the mechanisms causing calf survival to fluctuate has become increasingly important as many local moose populations in Scandinavia are declining and exposed to expanding predator populations, intense hunting pressure, and other threats associated with climate change. [ABSTRACT FROM AUTHOR]

Prey must balance resource acquisition with predator avoidance for survival and reproduction. To reduce risk of predation, prey may avoid areas with high predator use, but if they are unable to due to resource acquisition requirements, they may instead change their habitat use or movement speed to mitigate predation risk. Prey risk response may depend on spatially or temporally varying forage availability as well as seasonal variation in prey vulnerability and availability of alternate foods for predators. To quantify how prey respond to spatial and temporal variation in risk of brown bear predation, we examined Roosevelt elk (Cervus canadensis roosevelti) spatiotemporal behavior responses to brown bear (Ursus arctos) habitat use on Afognak and Raspberry islands, Alaska, using Global Positioning System location data during elk parturition (20 May–15 June), summer (16 June–20 September), and autumn (21 September–10 November). During parturition and summer, elk used forest and shrub landcover in areas of higher brown bear probability of use. During parturition, elk used areas with lower forage productivity in areas of higher bear probability of use, and movement speed decreased with higher bear probability of use, especially in shrub landcover. During summer, elk used areas with higher forage productivity in areas of higher brown bear probability of use. During autumn, elk were less likely to use areas with higher bear habitat probability of use across landcover categories and forage productivity. During summer and autumn, elk movement speed increased with higher brown bear probability of use. Elk behavioral response to risk of brown bear predation could increase energy expenditure and decrease their ability to acquire forage, therefore negatively impacting survival and reproduction with spatiotemporal variation in risk response potentially amplifying these impacts. [ABSTRACT FROM AUTHOR]

During the reproductive period, mating strategies are a significant driver of adaptations in animal behaviour. For instance, for polygamous species, greater movement rates during the mating season may be advantageous due to the increased probability of encountering several potential mates. The brown bear Ursus arctos is a solitary carnivore that lives at low densities, with a polygamous mating system and an extended mating season of nearly 3 months. Here, we hypothesized that male brown bears may show changes in movement patterns and space‐use behaviour during their mating season. Using long‐term (2002–2013) telemetry data from the Finnish Karelia male population (n = 24 individuals; n = 10 688 GPS locations), we first analysed daily movement metrics, that is, speed, net and total distance with respect to the period (mating vs. post‐mating) and several environmental predictors. Then, we conducted a step‐selection analysis for each of these periods. Throughout the year, male bears selected forested/shrub habitats and increased movement rates near main roads. During the mating season, reproductive needs seem to trigger roaming behaviour in adult males to maximize encounter rates with potential receptive females. However, all movement metrics increased within areas of high human activity, suggesting a bear response to a higher risk perception while using those areas. During the post‐mating period, overlapping with the bear hyperphagia and the hunting season, males selected anthropogenic areas farther from main roads and trails, suggesting a trade‐off between foraging opportunities and risk avoidance. [ABSTRACT FROM AUTHOR]

Context: Large carnivores have faced severe extinction pressures throughout Europe during the last centuries, where human-induced disturbances reached unprecedented levels. In the late twentieth century, the Cantabrian brown bear population was on the verge of extinction, due to poaching. Yet, the end of the last century was a turning point for this population. Presence data on the western Cantabrian subpopulation was collected since the beginning of the century and insights provided by this long-term monitoring may be useful for brown bear conservation. Objectives: Here, we aim to: (i) identify the landscape features relevant to bears’ recovery; and (ii) understand if and how the landscape use patterns by bears changed over time. Methods: We tested the influence of landscape structure (i.e., composition and configuration) on bear occurrence patterns using MAXENT in three periods representative of land cover change. Results: Despite variation across the 19-year monitoring period, brown bears were more often detected near broad-leaf forests and bare rock areas and at lower to intermediate altitudes, but avoided arable lands, permanent crops, and burnt areas. Human population density or distance to roads—often used for modelling habitat suitability for Cantabrian brown bears—were not identified as relevant variables for this brown bear subpopulation. Artificial areas were identified as relevant landscape features, but not as disturbance. Conclusions: These findings reinforce the importance of preserving bears’ native habitats and provide new insights, namely on the use of humanized landscapes. [ABSTRACT FROM AUTHOR]

Fertility control has traditionally been applied in zoos to control captive populations, and reversible contraception is important. However, contraceptive methods for male bears have not been reported. We aimed to establish a reversible contraceptive for male brown bears by investigating the effects of a gonadotropin‐releasing hormone (GnRH) vaccine (Improvac®) that was developed for the immune castration of pigs. We vaccinated six bears with two sequential doses of 400 (n = 2) or 600 μg Improvac® (n = 4) with a 1‐month interval during the pre‐breeding season (February to April). We compared the reproductive parameters (testosterone levels and semen parameters) of the six vaccinated and four non‐vaccinated (control) bears once during the breeding season (May or June). To investigate whether the reproductive performance could be restored in the following year of contraception, we also compared the reproductive parameters once during the breeding season in two bears between the year with GnRH vaccination and the following year without vaccination. Vaccination treatments suppressed reproductive parameters in 5 bears, although vaccination with 400 μg of Improvac® was not effective in one bear. Testosterone levels and the rate of progressive sperm motility were significantly lower, and total sperm count and testis size tended to be lower in vaccinated bears, compared with the controls. Blood biochemical findings and direct observations after Improvac® vaccination did not reveal side effects. Moreover, testosterone levels and spermatogenic scores of two bears were restored in the following year. We confirmed that the Improvac® vaccine elicited a reversible contraceptive effect in male brown bears. [ABSTRACT FROM AUTHOR]

The polar bear (Ursus maritimus) is a species particularly vulnerable to the effects of climate change. As the climate warms, polar bears will be forced to move to more suitable habitats which are likely to shrink, adapt to the new conditions, or decline in population size. However, the genomic diversity within and among all 19 subpopulations of polar bears, and therefore their adaptive potential, is currently unknown. In addition, warmer climates are likely to result in more frequent contact between polar bears and grizzly bears (U. arctos), with which they can hybridize. Here we describe the development, quality control, and application of the Ursus maritimus V2 SNP chip. This 8 K SNP chip contains loci explicitly selected to assess both RAD-derived and transcriptome-derived loci, as well as SNPs to detect hybridization between species. A total of 7,239 loci (90.3% of those printed) were successfully genotyped, with over 99% genotype concordance for individuals typed in duplicate on this chip, and between individuals typed here and on the Ursus maritimus V1 SNP chip. Using simulations, we demonstrate that the markers have high accuracy and efficiency to detect hybridization and backcrosses between polar bears and grizzly bears. However, empirical analysis of 371 polar bears, 440 grizzly bears, and 8 known hybrids found no novel instances of recent hybridization. The Ursus maritimus V2 SNP chip provides a powerful tool for monitoring the adaptive potential of this species along with assessing population structure, quantitative genomics, and hybridization in polar bears. [ABSTRACT FROM AUTHOR]

Hibernation is a key adaptation for coping with unfavorable climatic conditions and low food availability in areas with severe winter conditions. While understanding the physiology and phenology of this adaptation has received considerable attention, comparatively little information is available on how hibernation will be affected by changing climate conditions. We used GPS telemetry data from 20 free‐ranging brown bears monitored over 31 winters between 2007 and 2022, to identify behavioral strategies of bears during winter. We applied behavioral change point analysis to quantify brown bears' hibernation phenology in a population close to the bear's southern latitudinal range limit in Europe where supplementary food is available to bears year‐round. We observed winter behavior patterns that varied across age and reproductive classes but also within individuals between winters. Among 31 winter events, we registered six cases in which bears exhibited a single hibernation/stationary period and 19 events where hibernation was split into up to five stationary periods. Moreover, six winter events did not show behaviors consistent with hibernation and individuals remained partly or completely active throughout winter. The movement of these active bears decreased with increasing snow depth. In addition, these winter‐active bears showed higher fidelity to supplementary feeding sites during the winter period compared to the rest of the year. Our data suggest that an abundance of human‐provided food resources during winter may facilitate the emergence of different wintering strategies in brown bears. Furthermore, supplemental feeding sites in combination with predicted mild winters and prolonged natural food availability suggest that the use of hibernation as an energy‐saving strategy to overcome severe environmental conditions may decrease in the future. [ABSTRACT FROM AUTHOR]

Harvest regulations commonly attenuate the consequences of hunting on specific segments of a population. However, regulations may not protect individuals from non‐lethal effects of hunting and their consequences remain poorly understood. In this study, we compared the movement rates of Scandinavian brown bears (Ursus arctos, n = 47) across spatiotemporal variations in risk in relation to the onset of bear hunting. We tested two alternative hypotheses based on whether behavioural responses to hunting involve hiding or escaping. If bears try to reduce risk exposure by avoiding being detected by hunters, we expect individuals from all demographic groups to reduce their movement rate during the hunting season. On the other hand, if bears avoid hunters by escaping, we expect them to increase their movement rate in order to leave high‐risk areas faster. We found an increased movement rate in females accompanied by dependent offspring during the morning hours of the bear hunting season, a general decrease in movement rate in adult lone females, and no changes in males and subadult females. The increased movement rate that we observed in females with dependant offspring during the hunting season was likely an antipredator response because it only occurred in areas located closer to roads, whereas the decreased movement rate in lone females could be either part of seasonal activity patterns or be associated with an increased selection for better concealment. Our study suggests that female brown bears accompanied by offspring likely move faster in high‐risk areas to minimize risk exposure as well as the costly trade‐offs (i.e. time spent foraging vs. time spent hiding) typically associated with anti‐predator tactics that involve changes in resource selection. Our study also highlights the importance of modelling fine‐scale spatiotemporal variations in risk to adequately capture the complexity in behavioural responses caused by human activities in wildlife. [ABSTRACT FROM AUTHOR]

Harvest regulations commonly attenuate the consequences of hunting on specific segments of a population. However, regulations may not protect individuals from non‐lethal effects of hunting and their consequences remain poorly understood. In this study, we compared the movement rates of Scandinavian brown bears (Ursus arctos, n = 47) across spatiotemporal variations in risk in relation to the onset of bear hunting. We tested two alternative hypotheses based on whether behavioural responses to hunting involve hiding or escaping. If bears try to reduce risk exposure by avoiding being detected by hunters, we expect individuals from all demographic groups to reduce their movement rate during the hunting season. On the other hand, if bears avoid hunters by escaping, we expect them to increase their movement rate in order to leave high‐risk areas faster. We found an increased movement rate in females accompanied by dependent offspring during the morning hours of the bear hunting season, a general decrease in movement rate in adult lone females, and no changes in males and subadult females. The increased movement rate that we observed in females with dependant offspring during the hunting season was likely an antipredator response because it only occurred in areas located closer to roads, whereas the decreased movement rate in lone females could be either part of seasonal activity patterns or be associated with an increased selection for better concealment. Our study suggests that female brown bears accompanied by offspring likely move faster in high‐risk areas to minimize risk exposure as well as the costly trade‐offs (i.e. time spent foraging vs. time spent hiding) typically associated with anti‐predator tactics that involve changes in resource selection. Our study also highlights the importance of modelling fine‐scale spatiotemporal variations in risk to adequately capture the complexity in behavioural responses caused by human activities in wildlife. [ABSTRACT FROM AUTHOR]

Background: The co-existence between brown bears (Ursus arctos Linnaeus, 1758) and farmers in the Pyrenees has been a major concern for several decades. The bear's depredation on livestock has multiple implications for traditional practices of extensive grazing and calls for a better understanding of the various ways in which humans and non-humans interact across different territories. The present dataset stems from "The Pastoralism and Bears in the Pyrenees" research project led by the GEODE laboratory (UMR 5602 CNRS-UT2J) in partnership with the Association Dissonances. Focusing on three summer pastures as places of encounter, this project proposes to explore the definition of co-existence, based on context-dependent and constantly evolving relationships between bears and pastoralists. As part of an interdisciplinary approach combining animal geography and ecology, the spatio-temporal activity of the different species was explored using a network of 118 camera traps. New information: The 118 camera traps were installed on the three summer pastures while livestock was present in the mountains between May and October, from 2021 to 2023 and were set in a 400 m x 400 m grid covering a total area of around 2,000 ha. The present dataset contains 57,928 occurrences of 22 taxon categories, including 19 identified species, two family categories (equids and mustelids) and one class category (birds). As pastoral activity is significantly present in these areas, livestock (sheep (Ovis aries Linnaeus, 1758), equids, cows (Bos taurus Linnaeus, 1758) and goats ( Capra hircus Linnaeus, 1758)) account for 16,207 occurrences across the three pastures. The three main wild species captured over the three years and three pastures were the red deer (Cervus elaphus Linnaeus, 1758; 9,517 occurrences), red fox (Vulpes vulpes Linnaeus, 1758; 9,400 occurrences) and wild boar (Sus scrofa Linnaeus, 1758; 4,016 occurrences). Data are aggregated at the grid scale. Nonetheless, the exact locations of each camera trap as well as the photos can be requested from us. [ABSTRACT FROM AUTHOR]

Large carnivores have recently increased in number and recolonized in human‐dominated landscapes; however, their ecological roles in these landscapes have not been well studied. In the Shiretoko World Heritage (SWH) site, brown bears have recolonized a previously abandoned mosaic landscape of natural forests and conifer plantations after land abandonment. We previously reported that the bears had recently begun to dig for cicada nymphs in association with the creation of larch plantations. As a result, this digging activity decreased soil nutrients. To deepen the understanding of the novel ecological role of brown bears within human‐modified landscapes, we examined the impacts of brown bear digging on the growth of larch trees. We found that brown bear digging decreased fine root biomass of larch, soil water, and nitrogen availability. Brown bear digging negatively affected needle nitrogen content, but not carbon isotope ratios, a water stress index of trees. Tree ring data suggest that digging negatively affected the radial growth of larches. The results imply that digging decreases tree growth due to limited soil nitrogen uptake. Our findings indicate that the ecological roles of large carnivores may differ between natural and anthropogenic landscapes. [ABSTRACT FROM AUTHOR]

The Cantabrian brown bear (Ursus arctos) population is threatened although in a constant process of recovery during the last 20 years. Since data on the parasitological status of this bear is still limited, the objective of the present study was to assess the diversity and prevalence of parasites in this population. Thus, 111 bear faecal samples were collected in north-western Spain and analysed for estimating the occurrence of gastrointestinal and bronchopulmonary parasites. Samples were processed by flotation in saline and sucrose solution, sedimentation and Baermann-Wetzel techniques. In addition, a commercial immunofluorescent assay was performed for detecting Giardia duodenalis and Cryptosporidium spp. Dicrocoelium dendriticum was the most prevalent parasite (58.6%), followed by Baylisascaris transfuga (43.2%) and nematodes of the Suborder Strongylida (18.9%) and Spirurida (2.7%). Mixed infections were detected in the 41.4% of the samples. The presence of D. dendriticum was significantly highest in bears from the autonomous region of Castile and León as well as in those in which grass or nuts/acorns were the predominant food item. Moreover, the risk of being positive to B. transfuga was significantly higher during autumn–winter, and in those, faecal samples were mainly composed of fleshy fruit. Some of the parasites detected could infect other wildlife and even humans, and therefore, the risk of pathogen transmission deserves further investigation. Since the impact of endoparasites in the health status of bears is poorly understood, the establishment of a disease surveillance protocol is strongly recommended in order to assess the potential risk of these infections for bears. [ABSTRACT FROM AUTHOR]

Understanding mortality causes is important for the conservation of endangered species, especially in small and isolated populations inhabiting anthropized landscapes where both natural and human-caused mortality may hinder the conservation of these species. We investigated the mortality causes of 53 free-ranging brown bears (Ursus arctos) found dead between 1998 and 2023 in the Cantabrian Mountains (northwestern Spain), a highly human-modified region where bears are currently recovering after being critically threatened in the last century. We detected natural traumatic injuries in 52.63% and infectious diseases in 39.47% of the 38 bears for which the mortality causes were registered, with 21.05% of these cases presenting signs of both infectious diseases and traumas. More specifically, almost 30% of the bears died during or after intraspecific fights, including sexually selected infanticide (10.53%). In addition, primary infectious diseases such as infectious canine hepatitis, distemper, clostridiosis and colibacillosis caused the death of 15.79% of the bears. The number of direct human-caused deaths (i.e., shooting, poisoning, snare) decreased over the study period. This study also reveals three new mortality causes triggered by pathogens, two of which—Clostridium novyi and verotoxigenic Escherichia coli—not previously described in ursids, and the other one, canine distemper virus, never reported in brown bears as cause of death. New management strategies for the conservation of Cantabrian bears, which are urgently needed due to the rapid expansion of the population, should consider the mortality causes described in this study and must promote further research to elucidate how the high prevalence of infectious diseases may threaten the current recovery of the population. [ABSTRACT FROM AUTHOR]

How organisms obtain energy to survive and reproduce is fundamental to ecology, yet researchers use theoretical concepts represented by simplified models to estimate diet and predict community interactions. Such simplistic models can sometimes limit our understanding of ecological principles. We used a polyphagous species with a wide distribution, the brown bear (Ursus arctos), to illustrate how disparate theoretical frameworks in ecology can affect conclusions regarding ecological communities. We used stable isotope measurements (δ13C, δ15N) from hairs of individually monitored bears in Sweden and Bayesian mixing models to estimate dietary proportions of ants, moose, and three berry species to compare with other brown bear populations. We also developed three hypotheses based on predominant foraging literature, and then compared predicted diets to field estimates. Our three models assumed (1) bears forage to optimize caloric efficiency (optimum foraging model), predicting bears predominately eat berries (~70% of diet) and opportunistically feed on moose (Alces alces) and ants (Formica spp. and Camponotus spp; ~15% each); (2) bears maximize meat intake (maximizing fitness model), predicting a diet of 35%–50% moose, followed by ants (~30%), and berries (~15%); (3) bears forage to optimize macronutrient balance (macronutrient model), predicting a diet of ~22% (dry weight) or 17% metabolizable energy from proteins, with the rest made up of carbohydrates and lipids (~49% and 29% dry matter or 53% and 30% metabolizable energy, respectively). Bears primarily consumed bilberries (Vaccinium myrtillus; 50%–55%), followed by lingonberries (V. vitis‐idaea; 22%–30%), crowberries (Empetrum nigrum; 8%–15%), ants (5%–8%), and moose (3%–4%). Dry matter dietary protein was lower than predicted by the maximizing fitness model and the macronutrient balancing model, but protein made up a larger proportion of the metabolizable energy than predicted. While diets most closely resembled predictions from optimal foraging theory, none of the foraging hypotheses fully described the relationship between foraging and ecological niches in brown bears. Acknowledging and broadening models based on foraging theories is more likely to foster novel discoveries and insights into the role of polyphagous species in ecosystems and we encourage this approach. [ABSTRACT FROM AUTHOR]

Avoiding humans will be more difficult and energetically costly for animals as outdoor recreation increases and people venture farther into wildland areas that provide high‐quality habitat for wildlife. Restricting human access can be an attractive management tool to mitigate effects of human recreation activities on wildlife; however, the efficacy of such measures is rarely assessed. In 1982, Yellowstone National Park identified areas important to grizzly bears (Ursus arctos) to help protect critical grizzly bear habitat and reduce the likelihood of human injuries by bears. Referred to as bear management areas (BMAs), human access is restricted in these areas for 2–8 months each year, with timing and type of restrictions varying by area. We examined 2 datasets to evaluate grizzly bear selection of BMAs and differences of bear density in BMAs and non‐BMAs. First, we used 17 years of recent global positioning system telemetry data for grizzly bears to assess their selection of BMAs during periods when human access was allowed, and when access was restricted. We used step‐selection functions to test the hypothesis that bears spend time in places that allow them to avoid people and select quality food sources. There was support that grizzly bears differentially select for BMAs regardless of whether human access was restricted at the time, compared with areas outside BMAs, and that selection changed with sex and season. Only males during the summer and hyperphagic seasons changed their selection of BMAs based on whether access restrictions were in place, and overall, male bears preferred unrestricted BMAs (BMAs without restrictions in place). Females preferentially selected BMAs regardless of whether the area had access restrictions in place only during the mating season. Individuals varied widely in their preference for BMAs and access restrictions. Bears likely choose to spend time in BMAs based on available food resources rather than restrictions to human access. Supporting this interpretation, our analyses indicated that a greater proportion of BMA in an area was associated with higher densities of grizzly bear. Thus, restrictions to human access likely help reduce the potential for human–bear interactions, accomplishing one of the original objectives for establishing the BMAs. [ABSTRACT FROM AUTHOR]

Brown bears (Ursus arctos) were extinct in Portugal by 1843. In the spring of 2019, a male bear was officially confirmed in northern Portugal, and more bears will likely reach the country shortly. We surveyed participants in a workshop held in Bragança in October 2021 to understand the perceptions and attitudes of different stakeholder groups (Administration, Research, Nongovernmental Organizations, and Local Stakeholders) regarding the return of brown bears to Portugal. Results indicate that, generally, participants would feel safe in areas where bears are present, are positive toward the return of brown bears, and see it as an opportunity for local development rather than a threat. Results also indicate a high level of consensus among groups of stakeholders concerning the issues analyzed. These preliminary results provide a baseline for perceptions and attitudes to consider when planning the conservation of brown bears returning to Portugal. [ABSTRACT FROM AUTHOR]

Although the advent of high‐resolution GPS tracking technology has helped increase our understanding of individual and multispecies behavior in wildlife systems, detecting and recording direct interactions between free‐ranging animals remains difficult. In 2023, we deployed GPS collars equipped with proximity sensors (GPS proximity collars) on brown bears (Ursus arctos) and moose (Alces alces) as part of a multispecies interaction study in central Sweden. On 6 June, 2023, a collar on an adult female moose and a collar on an adult male bear triggered each other's UHF signal and started collecting fine‐scale GPS positioning data. The moose collar collected positions every 2 min for 89 min, and the bear collar collected positions every 1 min for 41 min. On 8 June, field personnel visited the site and found a female neonate moose carcass with clear indications of bear bite marks on the head and neck. During the predation event, the bear remained at the carcass while the moose moved back and forth, moving toward the carcass site about five times. The moose was observed via drone with two calves on 24 May and with only one remaining calf on 9 June. This case study describes, to the best of our knowledge, the first instance of a predation event between two free ranging, wild species recorded by GPS proximity collars. Both collars successfully triggered and switched to finer‐scaled GPS fix rates when the individuals were in close proximity, producing detailed movement data for both predator and prey during and after a predation event. We suggest that, combined with standard field methodology, GPS proximity collars placed on free‐ranging animals offer the ability for researchers to observe direct interactions between multiple individuals and species in the wild without the need for direct visual observation. [ABSTRACT FROM AUTHOR]

Copyright of Conservation Biology is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

A morphological description is provided for a unique find of a frozen mummified subfossil brown bear (Ursus arctos L., 1758), found for the first time ever. The find is a well-preserved bear carcass of approximately 3500 years in age. Results of computed tomography and DNA testing are discussed. [ABSTRACT FROM AUTHOR]

Copyright of Wildlife Monographs is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Herbivorous animals tend to seek out plants at intermediate phenological states to improve energy intake while minimizing consumption of fibrous material. In some ecosystems, the timing of green‐up is heterogeneous and propagates across space in a wave‐like pattern, known as the green wave. Tracking the green wave allows individuals to prolong access to higher‐quality forage. While there is a plethora of empirical support for such behavior in herbivorous taxa, the green wave hypothesis (GWH) is nuanced based on factors such as body morphometrics and digestive capacity. Furthermore, little is known about whether other taxa, such as omnivores, track the green wave. Our objective was to assess whether the GWH can be extended to explain the movements of omnivores. Using GPS collar data from seven populations (n = 127 individuals) of brown bears Ursus arctos across their entire North American range, we first tested whether bears tracked the green wave. Using conditional resource selection functions (RSFs), we found that variation in proxies of vegetative forage quality better explained movement and habitat selection than proxies of forage biomass in over half of the bears in our study, providing evidence of green wave tracking. Second, we assess factors that explained variation in green wave tracking using linear mixed effects models. Green wave tracking in brown bears was explained by the variation in availability of green‐up within spring home ranges, and how green‐up transitioned across those home ranges. Our results demonstrate that the GWH can partially explain movement of a non‐migratory omnivorous species, extending the generality of the GWH as a broad predictor of animal space use. The green wave is another resource wave brown bears track, and our findings help predict brown bear space use, which can be used to guide conservation and habitat restoration efforts. [ABSTRACT FROM AUTHOR]

Aggregated use along salmon‐bearing (Oncorhynchus spp.) streams is common for coastal brown bears Ursus arctos; however, it is much less common in non‐coastal (interior) environments, especially in the Arctic. A concurrent study of GPS‐collared brown bears in the interior Brooks Range mountains, northern Alaska, revealed that salmon‐bearing streams and their use by brown bears were more prevalent than previously known. Our goal was to estimate the number, gender, and species of bears (Ursus spp.) using anadromous streams while salmon were present in an area of northern, interior Alaska. We deployed single‐catch breakaway hair snares on heavily‐used bear trails along 7 km sections of two anadromous streams to identify individual animals through DNA genotypes. We collected 119 hair samples from August and September in 2016 and 2017 which revealed 31 unique brown bears and five American black bears Ursus americanus across both streams. Using a capture‐with‐replacement analysis, we estimated 24 (95% CI: 22–27) brown bears used 7 km of one stream and 15 (95% CI: 9–35) brown bears used 7 km of the other. Across both streams, we detected a higher proportion of females than males, more brown bears than black bears, and greater relatedness among bears that used the same stream. The high number of brown bears estimated along these streams belies their overall low densities in the region, while relatedness patterns suggests that bears obtain behavioral specialization through social learning. A 354 km industrial road is permitted to be constructed along the southern flanks of the Brooks Range, bisecting numerous streams and rivers, including the two sampled above. Given our findings, we identify potential mitigation measures to reduce human‐bear conflicts related to aggregated brown bear use along anadromous streams. [ABSTRACT FROM AUTHOR]

Understanding the density-dependent processes that drive population demography in a changing world is critical in ecology, yet measuring performance-density relationships in long-lived mammalian species demands long-term data, limiting scientists' ability to observe such mechanisms. We tested performance-density relationships for an opportunistic omnivore, grizzly bears (Ursus arctos, Linnaeus, 1758) in the Greater Yellowstone Ecosystem, with estimates of body composition (lean body mass and percent body fat) serving as indicators of individual performance over two decades (2000-2020) during which time pronounced environmental changes have occurred. Several high-calorie foods for grizzly bears have mostly declined in recent decades (e.g., whitebark pine [Pinus albicaulis, Engelm, 1863]), while increasing human impacts from recreation, development, and long-term shifts in temperatures and precipitation are altering the ecosystem. We hypothesized that individual lean body mass declines as population density increases (H1), and that this effect would be more pronounced among growing individuals (H2). We also hypothesized that omnivory helps grizzly bears buffer energy intake from changing foods, with body fat levels being independent from population density and environmental changes (H3). Our analyses showed that individual lean body mass was negatively related to population density, particularly among growing-age females, supporting H1 and partially H2. In contrast, population density or sex had little effect on body fat levels and rate of accumulation, indicating that sufficient food resources were available on the landscape to accommodate successful use of shifting food sources, supporting H3. Our results offer important insights into ecological feedback mechanisms driving individual performances within a population undergoing demographic and ecosystem-level changes. However, synergistic effects of continued climate change and increased human impacts could lead to more extreme changes in food availability and affect observed population resilience mechanisms. Our findings underscore the importance of long-term studies in protected areas when investigating complex ecological relationships in an increasingly anthropogenic world. [ABSTRACT FROM AUTHOR]

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During the Late Pleistocene, major parts of North America were periodically covered by ice sheets. However, there are still questions about whether ice‐free refugia were present in the Alexander Archipelago along the Southeast (SE) Alaska coast during the last glacial maximum (LGM). Numerous subfossils have been recovered from caves in SE Alaska, including American black (Ursus americanus) and brown (U. arctos) bears, which today are found in the Alexander Archipelago but are genetically distinct from mainland bear populations. Hence, these bear species offer an ideal system to investigate long‐term occupation, potential refugial survival and lineage turnover. Here, we present genetic analyses based on 99 new complete mitochondrial genomes from ancient and modern brown and black bears spanning the last ~45,000 years. Black bears form two SE Alaskan subclades, one preglacial and another postglacial, that diverged >100,000 years ago. All postglacial ancient brown bears are closely related to modern brown bears in the archipelago, while a single preglacial brown bear is found in a distantly related clade. A hiatus in the bear subfossil record around the LGM and the deep split of their pre‐ and postglacial subclades fail to support a hypothesis of continuous occupancy in SE Alaska throughout the LGM for either species. Our results are consistent with an absence of refugia along the SE Alaska coast, but indicate that vegetation quickly expanded after deglaciation, allowing bears to recolonize the area after a short‐lived LGM peak. [ABSTRACT FROM AUTHOR]

Hunters can affect the behavior of wildlife by inducing a landscape of fear, selecting individuals with specific traits, or altering resource availability across the landscape. Most research investigating the influence of hunting on wildlife resource selection has focused on target species and less attention has been devoted to nontarget species, such as scavengers that can be both attracted or repelled by hunting activities. We used resource selection functions to identify areas where hunters were most likely to kill moose (Alces alces) in south‐central Sweden during the fall. Then, we used step‐selection functions to determine whether female brown bears (Ursus arctos) selected or avoided these areas and specific resources during the moose hunting season. We found that, during both day and nighttime, female brown bears avoided areas where hunters were more likely to kill moose. We found evidence that resource selection by brown bears varied substantially during the fall and that some behavioral changes were consistent with disturbance associated with moose hunters. Brown bears were more likely to select concealed locations in young (i.e., regenerating) and coniferous forests and areas further away from roads during the moose hunting season. Our results suggest that brown bears react to both spatial and temporal variations in apparent risk during the fall: moose hunters create a landscape of fear and trigger an antipredator response in a large carnivore even if bears are not specifically targeted during the moose hunting season. Such antipredator responses might lead to indirect habitat loss and lower foraging efficiency and the resulting consequences should be considered when planning hunting seasons. [ABSTRACT FROM AUTHOR]

Malassezia pachydermatis (phylum Basidiomycota, class Malasseziomycetes) is a zoophilic opportunistic pathogen with recognized potential for invasive infections in humans. Although this pathogenic yeast is widespread in nature, it has been primarily studied in domestic animals, so available data on its genotypes in the wild are limited. In this study, 80 yeast isolates recovered from 42 brown bears (Ursus arctos) were identified as M. pachydermatis by a culture-based approach. MALDITOF mass spectrometry (MS) was used to endorse conventional identification. The majority of samples exhibited a high score fluctuation, with 42.5% of isolates generating the best scores in the range confident only for genus identification. However, the use of young biomass significantly improved the identification of M. pachydermatis at the species confidence level (98.8%). Importantly, the same MALDI-TOF MS efficiency would be achieved regardless of colony age if the cut-off value was lowered to ≥1.7. Genotyping of LSU, ITS1, CHS2, and β-tubulin markers identified four distinct genotypes in M. pachydermatis isolates. The most prevalent among them was the genotype previously found in dogs, indicating its transmission potential and adaptation to distantly related hosts. The other three genotypes are described for the first time in this study. However, only one of the genotypes consisted of all four loci with bear-specific sequences, indicating the formation of a strain specifically adapted to brown bears. Finally, we evaluated the specificity of the spectral profiles of the detected genotypes. MALDI-TOF MS exhibited great potential to detect subtle differences between all M. pachydermatis isolates and revealed distinct spectral profiles of bear-specific genotypes. [ABSTRACT FROM AUTHOR]

Aggregated use along salmon‐bearing (Oncorhynchus spp.) streams is common for coastal brown bears Ursus arctos; however, it is much less common in non‐coastal (interior) environments, especially in the Arctic. A concurrent study of GPS‐collared brown bears in the interior Brooks Range mountains, northern Alaska, revealed that salmon‐bearing streams and their use by brown bears were more prevalent than previously known. Our goal was to estimate the number, gender, and species of bears (Ursus spp.) using anadromous streams while salmon were present in an area of northern, interior Alaska. We deployed single‐catch breakaway hair snares on heavily‐used bear trails along 7 km sections of two anadromous streams to identify individual animals through DNA genotypes. We collected 119 hair samples from August and September in 2016 and 2017 which revealed 31 unique brown bears and five American black bears Ursus americanus across both streams. Using a capture‐with‐replacement analysis, we estimated 24 (95% CI: 22–27) brown bears used 7 km of one stream and 15 (95% CI: 9–35) brown bears used 7 km of the other. Across both streams, we detected a higher proportion of females than males, more brown bears than black bears, and greater relatedness among bears that used the same stream. The high number of brown bears estimated along these streams belies their overall low densities in the region, while relatedness patterns suggests that bears obtain behavioral specialization through social learning. A 354 km industrial road is permitted to be constructed along the southern flanks of the Brooks Range, bisecting numerous streams and rivers, including the two sampled above. Given our findings, we identify potential mitigation measures to reduce human‐bear conflicts related to aggregated brown bear use along anadromous streams. [ABSTRACT FROM AUTHOR]

Rubbing against various objects or self‐anointing with pungent substances are behaviours observed in many mammal species. The brown bear (Ursus arctos) is a non‐territorial species that rubs against trees with the main purpose being intraspecific communication. In addition, some odorous substances are known for eliciting rubbing behaviour and hence are used to lure bears to trees in studies relying on non‐invasive hair collection. Tree‐rubbing is often accompanied by clawing and debarking which release tree resin that impregnates the fur and can potentially deter ectoparasites. Here, we present a study aiming to determine whether ticks, being widely spread and an important vector of pathogens, are repelled by resin products known to attract bears and elicit rubbing behaviour, namely turpentine and beech tar. Dermacentor reticulatus ticks were offered a binary microhabitat choice by placing them in the middle of individual horizontal tubes with tested substances placed on filter paper at one end, and distilled water as a control (neutral) substance at the other. Their behaviour was recorded for three minutes. Ticks consistently touched the neutral end of the tube while avoiding treated ones. Overall, ticks remained at greater distances from treatments than from water. A fitted logarithmic regression showed ticks did not spend more than seconds at a treated side, supporting our prediction that ticks are repelled by turpentine and beech tar. Parasite repellency may bring a further advantage in rubbing behaviour trade‐offs, compensating some energetical costs, and adds a trait to the behaviour important in seemingly divergent contexts of intraspecific communication and defense against ectoparasites. [ABSTRACT FROM AUTHOR]

Intraspecific communication in mammals is well-documented but generally restricted to chemical and acoustic signaling. However, other overlooked channels, such as visual signaling, may be used to communicate among conspecifics. Here, by using experimental manipulations together with camera traps on 13 brown bear (Ursus arctos) rubbing trees in the Cantabrian Mountains (northwestern Spain), we document detailed temporal patterns and behavioral aspects of a recently discovered novel communication channel for this species, visual signaling through the trunk debarking of focal trees. Video footage showed that visual marking is a sex-, age-, and time-specific means of communication in brown bears, being performed exclusively by adult males during the mating season (mainly April–June in the study area). Trunk debarking was always associated with chemical marking and was never an isolated behavior, suggesting that visual and chemical signals might be complementary. Visual and chemical marks may provide different information; for example, visual marks could be an indicator of individual size and, thus, the dominance status of adult males looking for mating opportunities. This is the first time that evidence is provided showing that visual signaling in a large carnivore is exclusive to a specific class of individuals (adult males) and linked to reproductive needs only. Bear visual signaling not only represents an advance in our comprehension of animal communication but may also serve to easily locate the mating areas of mammals, which are crucial for large carnivore species, such as the brown bear, that frequently need specific and urgent plans for conservation and management. [ABSTRACT FROM AUTHOR]

Livestock depredation by brown bears is one of the main source of human–wildlife conflict in rural Eastern Europe. Thus, identifying environmental and anthropogenic drivers of human–bear conflict, and developing spatial predictions for predation intensity are critical to mitigate such conflicts. We used 756 records of bear‐caused livestock predation collected between 2008 and 2016 in the Romanian Carpathians and evaluated predictors and spatial distribution of bear livestock predation events (BPEs) using separate binomial generalized linear mixed models for cows, sheep, and other livestock. Despite differences in the direction and magnitude of the effect, the prevalence of BPE for all livestock was driven by the interaction between environmental drivers along with relative bear abundance. Distance from forest was a strong negative predictor for cows and sheep, while distance to villages was a strong negative predictor for cows. Landscape heterogeneity was positively associated with cow and other livestock predation and negatively associated with sheep. Relative bear abundance data collected by wildlife managers was a positive predictor for predation on all livestock. Livestock damage was more prevalent near villages, showcasing plasticity of food resources sought by bears. Our work informs brown bear and livestock management strategies to develop awareness and implement damage prevention measures. [ABSTRACT FROM AUTHOR]

Within optimal foraging theory animals should maximize their net energy gain while minimizing energetic costs. Energetic expenditure in wild animals is therefore key to measure proxies of fitness. Accelerometers are an effective tool to study animal movement-based energetics, but retrieval of the device is usually required and often difficult. Accelerometers measure movement across three axes (x, y, and z) and can be calibrated to measures of oxygen consumption from captive animals, providing estimates of overall energy expenditure. Measuring energetic expenditures using a global positioning system (GPS) approach could provide an alternative method to study energetic ecology. This technique uses locomotor speeds across a range of slopes from successive GPS locations, which can be linked to the energy expenditure from captive individuals. We compared accelerometer and GPS methods of energetic expenditures in free-roaming brown bears (Ursus arctos) on the Kodiak Archipelago, Alaska, USA. We then applied the GPS method to examine how multiple factors influenced brown bear movement-based daily energetic expenditures (MDEE). We found that while the two energetic measurements differed (Wilcoxon signed rank test: V = 2116, p < 0.001), they were positively correlated (r = 0.82, p < 0.001). The GPS method on average provided 1.6 times greater energy estimates than the accelerometer method. Brown bears had lower MDEE during periods of high food abundance, supporting optimal foraging theory. Reproductive status and age did not influence MDEE, however movement rates had a positive linear relationship. Energetic ecology is important for understanding drivers of animal movements. Data from GPS collars can provide useful information on energetic expenditures, but should be validated for the specific taxa, ecosystem, and GPS sampling rate used. Additionally, while movement-based estimates of energy expenditure can elucidate the mechanisms driving habitat use decisions, they may not fully reflect an animal's overall energy demands. Brown bear movement-based energetic expenditure was influenced by food abundance and movement rates, which highlighted the importance of access to prime foraging sites to enhance energetic efficiency. [ABSTRACT FROM AUTHOR]

In an era of increasing human pressure on nature, understanding the spatiotemporal patterns of wildlife relative to human disturbance can inform conservation efforts, especially for large carnivores. We examined the temporal activity and spatial patterns of wolves and eight sympatric mammals at 71 camera trap stations in Greece. Grey wolves temporally overlapped the most with wild boars (Δ = 0.84) and medium-sized mammals (Δ > 0.75), moderately with brown bears (Δ = 0.70), and least with roe deer (Δ = 0.46). All wild mammals were mainly nocturnal and exhibited low temporal overlap with human disturbance (humans, vehicles, livestock, and dogs; Δ = 0.18–0.36), apart from roe deer, which were more diurnal (Δ = 0.80). Six out of nine species increased their nocturnality at sites of high human disturbance, particularly roe deer and wolves. The detection of wolves was negatively associated with paved roads, the detection of roe deer was negatively associated with human disturbance, and the detection of wild boars was negatively associated with dogs. The detection of bears, boars, and foxes increased closer to settlements. Our study has applied implications for wolf conservation and human–wildlife coexistence. [ABSTRACT FROM AUTHOR]

Pulsed resources have prominent effects on community and ecosystem dynamics; however, there is little research on how resource pulses affect human–wildlife interactions. Tree masting is a common type of pulsed resource that represents a crucial food for many species and has important bottom‐up effects in food webs. In anthropogenic landscapes, years of food shortage after mast years can have negative outcomes for both people and wildlife, for instance when an increased use of anthropogenic foods by animals exacerbates human–wildlife conflicts. Here, we used novel remote sensing indicators of forest productivity and phenology, together with weather cues and ground measures of mast production, to assess whether years of masting and crop failures lead to changes in human–wildlife conflict occurrence. We used a unique 14‐year dataset including the production of European beech Fagus sylvatica seeds and brown bear Ursus arctos damage in the northeastern Carpathians as our model system. Linking these data in a panel regression framework, we found that temporal fluctuations in damage occurrence were sensitive to the year‐to‐year variation in beechnut production. Specifically, the number of damages during bear hyperphagia (i.e., September to December, when bears need to accumulate fat reserves prior to hibernation) was significantly higher in years with low beechnut production than in normal or mast years. Furthermore, we provide evidence that beech masting and failure can be predicted through a combination of remote‐sensing, weather, and field indicators of forest productivity and phenology. We demonstrate how pulsed resources, such as tree masting, can percolate through food webs to amplify human–wildlife conflict in human‐dominated landscapes. Given the recent range expansion of large carnivores and herbivores in many regions, including Europe, predicting years of natural food shortage can provide a pathway to proactive damage prevention, and thus to foster coexistence between wildlife and people. [ABSTRACT FROM AUTHOR]

Human–wildlife interactions (HWIs) are increasingly common human disturbances as development continues to remove wildlife habitats. Documenting HWI is critical for environmental protection agencies to develop strategies and management decisions that meet the needs of both people and wildlife. However, evaluation of the frequency and types of HWI at broad spatial scales (e.g., national or regional level) can be costly and difficult to implement by managers. In this study, we apply a novel method for the evaluation of patterns of HWI in urban areas by using publicly available data from emergency calls (ECs) placed by inhabitants of Romania's urban areas. We used information from 4601 ECs placed at the Romanian National Emergency Call System 112, which consisted of (1) wildlife species, (2) spatial location, (3) date and time, and (4) a short description of the emergency. Of the 318 analyzed cities, 300 cities documented ECs on HWI between 2015 and 2020, with roe deer and brown bear being the most frequently mentioned species. We recorded an increasing trend in HWI‐related ECs in 73% of the urban areas over the five‐year period. We mapped the large‐scale distribution of HWI by species and type of interactions in order to capture variations at the national level. Further, we analyzed the social and the biophysical factors potentially influencing the occurrence and frequency of HWI. The results showed that social factors have the same effect on all species, while the effect of the biophysical factors varied between species. Particularly, the presence of large natural habitats, represented by forests, influenced the number of calls only for brown bears. Seminatural landscapes with agricultural land have a different influence in terms of effect and significance for the considered species. Our results suggest that publicly available data from ECs can be used for the rapid assessment of HWI and for evaluating trends and predictors of HWI at broad spatial scales. [ABSTRACT FROM AUTHOR]

Brown bears hibernate throughout half of the year as a survival strategy to reduce energy consumption during prolonged periods with scarcity of food and water. Thyroid hormones are the major endocrine regulators of basal metabolic rate in humans. Therefore, we aimed to determine regulations in serum thyroid hormone levels in hibernation compared to the active state to investigate if these are involved in the adaptions for hibernation. We used electrochemiluminescence immunoassay to quantify total triiodothyronine (T3) and thyroxine (T4) levels in hibernation and active state in paired serum samples from six subadult Scandinavian brown bears. Additionally, we determined regulations in the liver mRNA levels of three major thyroid hormone-binding proteins; thyroxine-binding globulin (TBG), transthyretin (TTR), and albumin, by analysis of previously published grizzly bear RNA sequencing data. We found that bears were hypothyroid when hibernating with T4 levels reduced to less than 44% (P = 0.008) and T3 levels reduced to less than 36% (P = 0.016) of those measured in the active state. In hibernation, mRNA levels of TBG and albumin increased to 449% (P = 0.031) and 121% (P = 0.031), respectively, of those measured in the active state. TTR mRNA levels did not change. Hibernating bears are hypothyroid and share physiologic features with hypothyroid humans, including decreased basal metabolic rate, bradycardia, hypothermia, and fatigue. We speculate that decreased thyroid hormone signaling is a key mediator of hibernation physiology in bears. Our findings shed light on the translational potential of bear hibernation physiology to humans for whom a similar hypometabolic state could be of interest in specific conditions. [ABSTRACT FROM AUTHOR]

While the location of wildlife mortalities provides some insight on the cause of death, identifying the risk factors associated with mortality events and in which cases these factors result in death requires information on individual behaviour prior to death. With access to a long-term database of grizzly bear (Ursus arctos L., 1758) GPS locations, we investigated how behaviour differed between individuals that died of anthropogenic causes and those that survived across different temporal scales. We analyzed movement (diurnality and daily displacement) and habitat use (modelled risk and habitat quality) of grizzly bears residing in Alberta, Canada, from 2005 to 2021 to determine whether grizzly bears that died and grizzly bears that survived differed in these behaviours 2–4 years, 1 year, and 1 week prior to death, and whether patterns changed over time. We found that diurnality increased in the last year of life, while displacement increased in the last week of life, with differences becoming greater nearer the day of death. Grizzly bears that died used high-risk and low-quality habitat at all time scales, and these behaviours increased as death approached. Our analysis suggests that grizzly bear mortalities do not occur randomly but happen at times when individuals exhibit high-risk behaviours. This information can be used to make management decisions related to habitat management, road use, and human access. [ABSTRACT FROM AUTHOR]

Roads are human infrastructure that heavily affect wildlife, often with marked impacts on carnivores, including brown bears Ursus arctos. Here, we assessed the potential impact of road networks on the distribution of brown bears in the small, isolated and endangered Cantabrian population of north‐western Spain. To ascertain whether local road networks affect brown bear spatial distribution, we first assessed potential influences on the distance of bear locations to roads using candidate models which included topographic variables, landcover types, bear age and reproductive status, traffic volume and road visibility. Then, we built two sets of habitat suitability models, both with and without roads, to discern the possible loss of habitat suitability caused by roads. The mean distance of bear locations to the nearest road was 968 ± 804 m and the closest road was a low traffic road in 72.5% of cases. Candidate models showed little influence of our variables on bear distance to the nearest road, with the exception of elevation. Habitat suitability models revealed that road networks in our study area seem to have almost no effect on brown bear habitat suitability, except for females with yearlings during the denning season. However, this result may also be a consequence of the fact that only a small proportion (16.5%) of the cells classified as suitable bear habitats were crossed by roads, that is, most of the roads are primarily located in unsuitable bear habitats in the Cantabrian Mountains. Compared to previous studies conducted in other populations, mainly North American ones, our findings might suggest a different response of Eurasian brown bears to roads due to a longer bear‐human coexistence in Europe versus North America. However, the indirect approach used in our study does not exclude other detrimental effects, for example, road mortality, increased stress and movement pattern disruption, only detectable by more direct approaches such as telemetry. [ABSTRACT FROM AUTHOR]

Ecosystem services are the benefits that people gain directly or indirectly from the ecosystems. Golestan National Park as one of the world's biosphere reserves and one of the best habitats of brown bears (Ursus arctos) as the biggest carnivore in the country, has been truly important. The brown bear has been considered a model species in this research due to its high ecological value. Assessment models of habitat and ecosystem services can be used as a suitable tool for conservation, planning, and management purposes. Ecosystem service indicators were determined through the Co$ting Nature web model and based on the results, the entire region had the highest priority for protection. The index of region future threats showed the average threat (0.55) in 77% of the national park area. However, the potential ecosystem services index showed that 50.9% of the park has a high potential for ecosystem services. Mainly, Golestan National Park has a suitable quality brown bear habitat and it has relatively appropriate conditions in terms of ecosystem services. However, it is necessary to adopt strategies to protect the region and improve the conditions, especially in the area of the Tehran-Mashhad Road in Golestan national park. [ABSTRACT FROM AUTHOR]

The brown bear Ursus arctos undergoes exceptional physiological adaptions during annual hibernation that minimize energy consumption, including profound decrease in heart rate, cardiac output, and respiratory rate. These changes are completely reversible after the bears reenter into the active state in spring. In this case report, we show episodes of sinus arrest in a hibernating Scandinavian brown bear and in humans, recorded by implantable loop recorders and discuss the possible underlying mechanisms. Lessons learned from cardiac adaptations in hibernating bears might prove useful in the treatment of patients with sinus node dysfunction. [ABSTRACT FROM AUTHOR]

Trapping bears (Ursidae) with Aldrich leg snares has established itself as one of the most successful methods of trapping live animals with minimal injury. Most documented injuries are related to damage caused by the trap and prolonged exposure to it. Various physiological and behavioural responses have been observed, however self-eating of the toes of the captured foot has not been described so far. In November 2017 an adult male brown bear was caught with a standard Aldrich type leg snare. When the research team arrived, the bear teared off and swallowed phalanges of the first toe of its rear left foot before it could be sedated. The bear was measured and marked with GPS-GSM collar. Following the instalment of the collar, the animal was monitored for the duration of 23 months when the drop-off mechanism of the collar was activated. This rule out the possibility that a serious life threatening complications arised from the trauma. [ABSTRACT FROM AUTHOR]

Species distribution models (SDMs) are powerful tools in ecology and conservation. Choosing the right environmental drivers and filtering species' occurrences taking their biases into account are key factors to consider before modeling. In this case study, we address five common problems arising during the selection of input data for presence‐only SDMs on an example of a generalist species: the endangered Cantabrian brown bear. First, we focus on the selection of environmental variables that may drive its distribution, testing if climatic variables should be considered at a 1‐km analysis grain. Second, we investigate how filtering the species' data in view of (1) their collection procedures, (2) different time frames, (3) dispersal areas, and (4) subpopulations affects the performance and outputs of the models at three different spatial analysis grains (500 m, 1 km, and 5 km). Our results show that models with different input data yielded only minor differences in performance and behaved properly in terms of model validation, although coarsening the analysis grain deteriorated model performance. Still, the contribution of individual variables and the habitat suitability predictions differed among models. We show that a combination of limited data availability and poor selection of environmental variables can lead to inaccurate predictions. Specifically for the brown bear, we conclude that climatic variables should not be considered for exploring habitat suitability and that the best input data for modeling habitat suitability in the study area originate from (1) observations and traces from the (2) most recent period (2006–2019) in which the population is expanding, (3) not considering cells of dispersing bear occurrences and (4) modeling subpopulations independently (as they show distinct habitat preferences). In conclusion, SDMs can serve as a useful tool for generalist species including all available data; still, expert evaluation from the perspective of data suitability for the purpose of modeling and possible biases is recommended. This is especially important when the results are intended for management and conservation purposes at the local level, and for species that respond to the environment at coarse analysis grains. [ABSTRACT FROM AUTHOR]

Significant palaeoecological and paleoclimatic changes that took place during Late Pleistocene—Early Holocene transition are considered important factors that led to megafauna extinctions. Unlike many other species, the brown bear (Ursus arctos) has survived this geological time. Despite the fact that several mitochondrial DNA clades of brown bears became extinct at the end of the Pleistocene, this species is still widely distributed in Northeast Eurasia. Here, using the ancient DNA analysis of a brown bear individual that inhabited Northeast Asia in the Middle Holocene (3460 ± 40 years BP) and comparative phylogenetic analysis, we show a significant mitochondrial DNA similarity of the studied specimen with modern brown bears inhabiting Yakutia and Chukotka. In this study, we clearly demonstrate the maternal philopatry of the Northeastern Eurasian U. arctos population during the several thousand years of the Holocene. [ABSTRACT FROM AUTHOR]

The mechanisms determining habitat use in animal populations have important implications for population dynamics, conservation, and management. Here, we investigated how an increase in annual numbers of brown bear females with cubs of the year (FCOY) in a growing, yet threatened population, could explain differences in the habitat characteristics around reproductive dens. Habitat characteristics around FCOY dens were compared between a low bear density period (1995–2005) and a period when the population was increasing (2006–2016). We also compared the distance to the nearest breeding area and to all other breeding areas observed during the same year. The results suggested that during the second period, breeding areas were closer to rivers, fruit trees, and anthropogenic sources of disturbance (trails, highways) than in 1995–2005. There were also shorter distances to the closest neighboring breeding area, while the mean distance among FCOY breeding areas increased as the population grew and expanded at the landscape level. These changes may reflect that the best den locations were increasingly occupied (i.e., ideal-despotic distribution), and may be further explained by the avoidance of conspecifics by FCOY in a critical time of the year, when newborn cubs are most vulnerable. We suggest that both density-dependent factors and human-related features of the landscape are crucial to understanding long-term dynamics in the habitat use of a threatened species. [ABSTRACT FROM AUTHOR]

Salmon (Oncorhynchus spp.) are an important food source for Grizzly Bear (Ursus arctos), but many salmon populations are declining. While most research on Grizzly Bear-salmon interactions occurs in coastal ecosystems, declining salmon may also affect Grizzly Bears in inland ecosystems where salmon are also an important part of their diet. We document changes in the number and distribution of observations of Grizzly Bears and changing Kokanee (i.e., landlocked Sockeye Salmon, Oncorhynchus nerka) abundance at an inland river. We hypothesized that reduced abundance of Kokanee would limit the number of Grizzly Bear observations at the river. We compared Kokanee abundance and Grizzly Bear observations (n = 535) between 2012 and 2019 at the Lardeau River, British Columbia, Canada. We used a generalized linear mixed model to test if the number of bear observations changed as a function of Kokanee abundance among four river reaches during eight consecutive years of study. Kokanee abundance was a strong statistical predictor of Grizzly Bear observations (ß = 0.52, P = 0.001, CI = 0.12-0.87), and Kokanee abundance and reach explained 73% of the variance. Our results suggest that reduced Kokanee abundance also reduces Grizzly Bear presence, likely because bears seek out other, more available food sources, away from Kokanee spawning habitat. This pattern could limit ecosystem services provided by Grizzly Bears adjacent to spawning areas and it could have implications for bear management and conservation. [ABSTRACT FROM AUTHOR]

The increasing demand for resources to meet the needs of our society has transformed the environment and increased the likelihood of human-wildlife interactions. Romania has the highest density of brown bears in Europe, with more than 7000 individuals populating the Carpathian Mountains and neighboring areas. The large brown bear population in Romania inhabits ever-increasing human-dominated landscapes, which frequently results in conflict with humans. The means and frequency by which the media communicates information to the readership influence the public perception of human-wildlife conflicts. This research is intended to contribute to the existing knowledge on human-brown bear coexistence in Romania by (1) exploring how the Romanian media depicts human-brown bear interactions in terms of the main themes discussed, framing of issues (emotions and key messages), and likely impacts on public perception; (2) analyzing the changes in reporting on human brown-bear interactions following the transition of the legal status of the brown bear from game to strictly protected species; and (3) investigating suggested policy and management solutions. The results indicate that news stories related to brown bears became common in Romanian mass media after 2016, when a provisional one-year ban on culling was instated, after which it increased abruptly in 2021, following the whistleblowing of an alleged trophy hunting event. The focus on human-bear interaction and hunting/poaching themes has not changed; however, the position of the media toward brown bears has become increasingly negative, even when presenting news stories covering human-bear interactions that incur no harm. To facilitate human-brown bear coexistence in Romania, scientists and practitioners should communicate with media representatives and provide a supplementary context for news stories. Evidence-informed news can help authorities better understand conflicts and create bottom-up pathways toward an optimistic future for brown bears and Romanian society. [ABSTRACT FROM AUTHOR]

Knowledge concerning the relative importance of biotic and abiotic factors associated with the long-term settlement of large carnivores in human-dominated landscapes is important for effective species conservation. However, identifying the major drivers of large carnivore occurrences at a continental scale is challenging as several factors can act in concert to affect large carnivore distributions. Thus, we investigated the relationship between the permanent and sporadic occurrences of large carnivores (brown bear, Eurasian lynx, grey wolf and wolverine) and three groups of predictor variables (i.e., landscape attributes, human disturbance and prey availability) on the continental scale in Europe. Specifically, we used generalized linear models (GLMs) and variation partitioning to estimate the independent and cumulative effects of the three predictor groups on large carnivore occurrences. The explained variance for permanent vs. sporadic occurrence was highest for the wolverine (42.8% and 29.7%), followed by the brown bear (20.5% and 16.4%), Eurasian lynx (15.2% and 11.6%) and grey wolf (15.8% and 6.1%). Landscape attributes, such as forest cover, shrub-land cover, altitude and slope, were positively related to the occurrence of grey wolf, brown bear and Eurasian lynx, whereas human disturbance (human population density, distance to roads and to human settlements) was negatively related to wolverine occurrence. For all species, shared effects between landscape attributes and human disturbance accounted for a considerable portion of the explained variation in both permanent and sporadic occurrence, and landscape attributes were generally more important for explaining permanent than sporadic occurrence, except for the wolverine. Prey availability was marginally associated with the permanent occurrence of the grey wolf but we found no statistical effect of prey availability on the occurrence of the other large carnivores. In conclusion, the sporadic occurrence of large carnivores in Europe is more stochastic and less predictable than their permanent occurrence. Landscape attributes and their joint effects with human disturbance are the most important factors related to the recolonization dynamics of large carnivores, although wolverine distributions appear strongly limited by human disturbance itself. Domestic prey availability seems to play a subordinate role in driving the recent distribution dynamics of large carnivores at the continental scale. Thus, our results are relevant also in light of the ongoing recolonization of large carnivores which, in many rural areas, caused concerns among the locals, especially in relation to conflicts with human activities. For these reasons, we stress the need to continue and improve large carnivore monitoring across Europe. [ABSTRACT FROM AUTHOR]

The daily activity patterns of animals are modulated by external factors such as habitat selection, temporal niche selection, prey availability and predation risk. Furthermore, different species show a variety of responses to human disturbance; therefore, to understand the effects of human activities on wildlife, it is crucial to consider the disturbance characteristics (e.g. type, frequency, timing and location of human activity). Our objective was to evaluate whether vehicles on forest roads altered the daily temporal activity patterns of three apex predators; Eurasian lynx (Lynx lynx), the grey wolf (Canis lupus) and brown bear (Ursus arctos), using an extensive camera trap data set collected across a gradient of forest roads and wildlife trails in the Croatian part of the Dinaric mountains. We expected a low temporal overlap between humans and apex predators but predicted this even lower at sites where vehicles are present. Consistent with our expectations, the general overlap in temporal activity of all three apex predators and humans was low, the former being primarily active at night/dawn/dusk hours and the latter during daylight hours. In contrast, our results showed similarity in the temporal activity of all three predators on wildlife trails and forest roads where human activity was more frequent and diverse. [ABSTRACT FROM AUTHOR]