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19 pages, 7787 KB  
Article
High-Mountain Carnivore Assemblage and Sustainable Conservation Priorities in the K2 Landscape
by Muhammad Shakil, Zubair Shah, Shoaib Hameed, Ejaz Ur Rehman, Fathul Bari, Sadam Hussain, Tahir Mehmood, Shakeel Ahmad, Tahir Mehmood and Muhammad Ali Nawaz
Sustainability 2026, 18(8), 3888; https://doi.org/10.3390/su18083888 - 14 Apr 2026
Viewed by 522
Abstract
Mammalian carnivores play an important role in maintaining the integrity of an ecosystem; therefore, their conservation as an umbrella species ensures the conservation of other species as well as the entire ecosystem. The northern area of Pakistan has a rich diversity of globally [...] Read more.
Mammalian carnivores play an important role in maintaining the integrity of an ecosystem; therefore, their conservation as an umbrella species ensures the conservation of other species as well as the entire ecosystem. The northern area of Pakistan has a rich diversity of globally and regionally significant carnivore species, many of which are threatened mainly due to conflict with humans. In the current study, we used multiple survey techniques: camera trapping, sign surveys, and questionnaire surveys in the Basha–Braldu Valleys of the Central Karakoram National Park (CKNP) during the period 20 May–31 July 2017. The objectives were to document mammalian carnivore diversity and relative abundance and to assess community perceptions of carnivores and human–carnivore conflicts associated with economic losses from livestock depredation. Camera trapping was only carried out in the Basha valley, where 30 motion-triggered cameras were deployed for two months, maintaining a minimum spatial distance of 1 km between the nearest cameras. Sign surveys were carried out in both valleys by dividing the area into 5 km × 5 km grids. Signs of carnivores were searched in a 50 m radius of the sampling point, and a minimum distance of 100 m was maintained between the two nearest sampling points. The questionnaire survey was conducted in communities residing in both valleys. Overall, 140 randomly selected locals from 23 villages were interviewed about the human–carnivore interaction in the area. The questionnaire covered the respondents’ demographics, carnivore sightings and status, economic loss due to livestock depredation, and local perceptions towards carnivores. The study confirmed the presence of seven carnivore species, including the snow leopard (Panthera uncia), grey wolf (Canis lupus), red fox (Vulpes vulpes), brown bear (Ursus arctos), Himalayan lynx (Lynx lynx), stone marten (Martes foina), and weasel (Mustela altaica). Of the total livestock losses reported, carnivores accounted for 30% (394 animals), while 70% (1347 animals) were attributed to disease, resulting in an overall economic loss of USD 138,778 (USD 991 per household). Livestock depredation varied with season, prey type, location, livestock guarding practices, and predator species. Due to high levels of livestock depredation, local communities perceived the grey wolf as the most dangerous carnivore, with many respondents favoring its reduction or elimination. Our findings indicate that the Basha–Braldu Valleys support a rich diversity of globally important carnivore species; however, human–carnivore conflict driven by livestock depredation remains a major conservation challenge. Effective conflict-mitigation interventions are essential to promote sustainable conservation practices and long-term coexistence within these mountain ecosystems. Further studies are recommended to improve the understanding of carnivore population status, distribution, and dietary ecology. Full article
(This article belongs to the Section Environmental Sustainability and Applications)
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15 pages, 1325 KB  
Article
Activity Patterns of Black Bears (Ursus americanus) and Their Relationship with the Enhanced Vegetation Index (EVI) in the El Cielo Biosphere Reserve, Tamaulipas, Mexico
by Jesse R. Wong-Smer, Jorge V. Horta-Vega, Crystian S. Venegas-Barrera, Rogelio Carrera-Treviño, Yuriana Gómez-Ortiz and Leroy Soria-Díaz
Ecologies 2026, 7(2), 34; https://doi.org/10.3390/ecologies7020034 - 9 Apr 2026
Viewed by 403
Abstract
The daily activity patterns of wild animal species are driven by environmental conditions and plant productivity although the degree of dependence varies according to their ecological niche. Bear ecology is intrinsically linked to seasonal vegetative availability. As omnivores with high metabolic demands, these [...] Read more.
The daily activity patterns of wild animal species are driven by environmental conditions and plant productivity although the degree of dependence varies according to their ecological niche. Bear ecology is intrinsically linked to seasonal vegetative availability. As omnivores with high metabolic demands, these species rely heavily on botanical resources including fruits, seeds, and roots. Consequently, differences in primary productivity across the landscape influence how individuals distribute their circadian activity patterns. The Enhanced Vegetation Index (EVI) is a tool that quantifies the quality and vigor of vegetation. Relating the EVI to activity patterns allows us to understand how vegetation dynamics and conditions influence the use of time at different times of the day. This study analyzes the daily activity pattern of the American black bear (Ursus americanus) in the El Cielo Biosphere Reserve (ECBR) using camera traps and its association with spatial variations in the Enhanced Vegetation Index (EVI). The results show that the daily activity pattern of the American black bear in the ECBR exhibits a diurnal–crepuscular tendency. In areas with high primary productivity and higher temperatures, activity occurs before sunrise and at sunset, with low activity during the rest of the day. In contrast, in areas with less vegetation and lower temperatures, activity occurs throughout the day. This suggests that, in the ECBR, the activity pattern of black bears could be modulated by temperature variations related to changes in vegetation productivity. Full article
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21 pages, 9880 KB  
Article
Investigating Intraspecific Attacks in Brown Bears (Ursus arctos) Using a Forensic Approach: Evidence from Northern Italy
by Cristina Marchetti, Roberto Guadagnini, Rosanna Di Lecce, Luca Ferrari, Gennaro Carrozzo, Sofia Guadagnini and Andrea Mazzatenta
Animals 2026, 16(7), 1119; https://doi.org/10.3390/ani16071119 - 6 Apr 2026
Viewed by 851
Abstract
Fatal intraspecific aggression in brown bears (Ursus arctos) remains poorly documented, yet elucidating its dynamics is critical in order to understand species’ physiology, informing management strategies, and advancing wildlife forensic science applications, which are useful in cases where a natural or [...] Read more.
Fatal intraspecific aggression in brown bears (Ursus arctos) remains poorly documented, yet elucidating its dynamics is critical in order to understand species’ physiology, informing management strategies, and advancing wildlife forensic science applications, which are useful in cases where a natural or illegal cause of death needs to be discerned. In this study, we reported four confirmed cases of lethal aggression (two yearlings and two adults) in the Italian Alps. Comprehensive autopsies were performed to characterize lesion patterns and infer the aggressor identity. Claw-induced lacerations, bite marks and the aspect of hemorrhages suggested the attack sequence. Aggressor identity was investigated by using forensic odontology through inter-canine distance (I-CD) and genetic analysis of peri-lesional saliva. I-CD allowed us to plausibly hypothesize the aggressor’s species and, in the cases where it was possible, to classify the sex and/or age group of the aggressors. While genetic analysis allowed the identification of the four brown bear victims, it did not provide informative results on the aggressors. The cause and manner of death were coded according to international criteria (International Classification of Diseases 11th Revision [ICD-11], WHO). Adult fatalities, supported by gastric content analysis, reflect trophic competition regardless of the mating context and highlight the role of anthropogenic food sources in conflict emergence. These findings underscore the value of integrated approaches in wildlife investigations and provide new insights into ecophysiological factors driving lethal intraspecific aggression. Full article
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23 pages, 1485 KB  
Review
Tradeoffs Among Predator Control, Moose Harvests, and Trophy Antlers: Principles Pertinent to Managing Alaska’s Wildlife
by R. Terry Bowyer, Sterling D. Miller and David K. Person
Animals 2026, 16(3), 472; https://doi.org/10.3390/ani16030472 - 3 Feb 2026
Viewed by 1520
Abstract
The State of Alaska, USA, has a long and controversial history of controlling predators to enhance ungulate populations, including moose (Alces alces). Moose management is complicated by a dual system in which the Federal and State governments prioritize harvesting moose for [...] Read more.
The State of Alaska, USA, has a long and controversial history of controlling predators to enhance ungulate populations, including moose (Alces alces). Moose management is complicated by a dual system in which the Federal and State governments prioritize harvesting moose for human consumption over other considerations, such as trophy or sport hunting, but have conflicting regulations regarding who is eligible to harvest moose. Wildlife management for the State is overseen by the Alaska Board of Game (BOG), with advice from the Alaska Department of Fish and Game (ADFG). In accordance with its Intensive Management Policy, the BOG establishes regulations promoting the harvest of moose and other ungulates for human consumption. This typically occurs by controlling bears (Ursus americanus and U. arctos) and gray wolves (Canis lupus) in anticipation of increasing ungulate harvests, often without adequate information on the status and ecology of predator or ungulate populations. We provide a narrative and integrative review of moose population dynamics to help resolve those issues. We argue that the current management of moose and their predators in Alaska does not encompass a full range of management options and fails to consider or implement important aspects of their population dynamics. Predators maintain some moose populations at a low density, reducing the harvest of moose but promoting large-antlered individuals, which are of value to Alaska’s professional guide and tourism industries. Using modern models of population dynamics of moose and other ungulates, we argue that if the proximity of the moose population to K (the ecological carrying capacity) is known, management strategies that increase the human harvest of moose and also promote large-antlered trophies are not mutually exclusive. We list life history and population characteristics to help determine the nutritional status of moose populations in relation to K, thereby guiding wise management of that valuable resource. We also recommend an adaptive management approach to assessing the effects of such activities. We caution, however, that to wisely manage these important wildlife resources, more information on the dynamics of moose and their predators is necessary. A system that embraces more biology and fewer politics would provide greater opportunities to employ the best science in the management of moose and their predators. Full article
(This article belongs to the Section Wildlife)
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22 pages, 2797 KB  
Article
Vocal and Non-Vocal Communication of American Black Bears (Ursus americanus): Implications for Conservation
by Benjamin Kilham, James R. Spotila and Andrew A. Timmins
Conservation 2026, 6(1), 17; https://doi.org/10.3390/conservation6010017 - 3 Feb 2026
Viewed by 1622
Abstract
To establish the best approach for conserving a species, it is necessary to understand the biology of that species. To better understand the behavior of American black bears (Ursus americanus), we observed 246 black bears for 7950 h in nature over [...] Read more.
To establish the best approach for conserving a species, it is necessary to understand the biology of that species. To better understand the behavior of American black bears (Ursus americanus), we observed 246 black bears for 7950 h in nature over a 24-year period to quantify how the bears communicated. Black bears communicated using several different behaviors. These included thirteen types of vocalizations, eight olfactory behaviors, eight marking behaviors, sixteen different body postures and gestures constituting their body language, and various emotional expressions. Some behaviors appeared to be automatic, including facial expression, ear movements, some forms of body language, the intensity of various vocalizations, and various moans. Other behaviors appeared to be intentional, including mechanically generated sounds and actions that could be used to bluff or deceive, such as the chomping of teeth, huffing, swatting, false charging, and various vocalizations. The conservation of black bears can be improved by establishing management strategies that take into account the vocal and non-vocal communication of the bears. Conflicts and negative encounters between humans and bears can be reduced through behavioral modifications by humans based on our new understanding of the communication system of bears. Knowledge of the communication system of the black bear provides a basis for improved conservation through the non-lethal management of bears involved in bear–human conflicts. Full article
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14 pages, 2680 KB  
Article
The Establishment of Asian Black Bear (Ursus thibetanus) Fibroblast Cell Line
by Yujuan Hu, Wanrong Song, Liwei Zhang, Longyue Yuan and Yipeng Jin
Animals 2026, 16(3), 436; https://doi.org/10.3390/ani16030436 - 30 Jan 2026
Cited by 1 | Viewed by 364
Abstract
The Asian black bear (Ursus thibetanus, UT), a Class II protected species in China, presents significant challenges for dermatological research due to limited availability of skin specimens and technical difficulties in fibroblast isolation. To address this, this study developed an immortalized [...] Read more.
The Asian black bear (Ursus thibetanus, UT), a Class II protected species in China, presents significant challenges for dermatological research due to limited availability of skin specimens and technical difficulties in fibroblast isolation. To address this, this study developed an immortalized fibroblast cell line through lentiviral-mediated introduction of human telomerase reverse transcriptase (hTERT). The hTERT gene fragment was amplified via PCR and cloned into a eukaryotic expression plasmid using homologous recombination. The recombinant plasmid was packaged into lentiviral particles using a three-plasmid system (psPAX2, pMD2.G) for stable transduction of primary Ursus thibetanus skin fibroblasts (UTSF). Puromycin selection enabled isolation of positive clones, which were subsequently expanded to establish an immortalized cell line. Comprehensive validation through Western blotting, PCR and immunofluorescence confirmed successful genomic integration and sustained expression of hTERT. This study successfully immortalized the skin fibroblasts of black bears and established a fibroblast cell line of Asian black bears. This immortalized UTSF cell line provides a critical in vitro model system for investigating cutaneous physiology and pathogen interactions in this protected species. Full article
(This article belongs to the Section Mammals)
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20 pages, 3709 KB  
Article
Assessment of Human–Bear Conflict Through Time and Space: A Case Study from Ilgaz District, Türkiye
by Atilla Dinçer Kara, Derya Gülçin, Efehan Ulaş, Elif Yıldız Ay, Özkan Evcin, Kerim Çiçek, Javier Velázquez and Ali Uğur Özcan
Conservation 2026, 6(1), 13; https://doi.org/10.3390/conservation6010013 - 26 Jan 2026
Viewed by 1475
Abstract
The brown bear (Ursus arctos) occurs across several regions of Türkiye and occasionally damages beehives near rural settlements. This study examines temporal data and the spatial arrangement of beehive damage incidents recorded in the Ilgaz district of Çankırı, Türkiye during 2023–2024. [...] Read more.
The brown bear (Ursus arctos) occurs across several regions of Türkiye and occasionally damages beehives near rural settlements. This study examines temporal data and the spatial arrangement of beehive damage incidents recorded in the Ilgaz district of Çankırı, Türkiye during 2023–2024. The temporal data were evaluated across lunar phases. A chi-square test showed that incidents did not distribute evenly. A higher frequency was found during the Waxing Crescent phase. Spatial intensity was mapped using Kernel Density Estimation (KDE), where bandwidth selection followed a cross-validation procedure. KDE results showed clear concentrations of incidents in the southern and southwestern parts of the district, while other areas recorded few or none. A Decision Tree (DT) classifier based on eleven environmental variables was used to identify predictors of incident presence. The DT achieved an AUC of 0.808. It identified “distance to settlement” as the primary separating variable, followed by “distance to road”, “distance to forest”, and the “Human Footprint Index”. Beehive damage followed a non-random temporal pattern across lunar phases. It clustered near settlements. Conflict timing followed both environmental conditions and human activity. The findings provide an empirical basis for reducing apiary losses and improving coexistence measures between local communities and brown bears in the Ilgaz region. Full article
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17 pages, 1700 KB  
Article
Urban River Microplastics as Vectors for Pharmaceutical Contaminants in a Savannah Region (Caatinga Biome)
by Yannice Tatiane da Costa Santos, Anderson Targino da Silva Ferreira, Lyndyanne Dias Martins, Hellen da Silva Sousa, Francisco Wedson Faustino, Maria Carolina Hernandez Ribeiro, Maria Kuznetsova, Anderson Zanardi de Freitas and Niklaus Ursus Wetter
Microplastics 2026, 5(1), 13; https://doi.org/10.3390/microplastics5010013 - 16 Jan 2026
Viewed by 534
Abstract
The study investigates the presence of emerging contaminants in a river within a watershed located in the Brazilian semiarid region, specifically within the Caatinga biome, emphasizing the importance of environmental monitoring in areas that have historically been underrepresented in scientific research. The analysis [...] Read more.
The study investigates the presence of emerging contaminants in a river within a watershed located in the Brazilian semiarid region, specifically within the Caatinga biome, emphasizing the importance of environmental monitoring in areas that have historically been underrepresented in scientific research. The analysis focused on the associations between microplastics and pharmaceutical compounds, demonstrating that the discharge of untreated domestic effluents and the low efficiency of sanitation systems increase water resource contamination and threaten water security. The interdependence between these variables underscores the need for integrated public policies for waste management, complemented by environmental education strategies and technological innovations. The work makes an unprecedented contribution to expanding knowledge about emerging pollutants in semiarid environments, highlighting the urgency of holistic approaches, continuous monitoring, and strengthening environmental governance to ensure the sustainability and resilience of ecosystems like the Caatinga in the face of the challenges posed by global environmental change, urban growth, and those outlined in the Sustainable Development Goals. Full article
(This article belongs to the Special Issue Microplastics in Freshwater Ecosystems)
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9 pages, 1090 KB  
Article
Conscious Indirect Blood Pressure Measurements in Asiatic Black Bears (Ursus thibetanus)
by Grace M. Scrafford, O. Lynne Nelson, Rachel Sanki, Sarah van Herpt and David Rice
Animals 2026, 16(1), 146; https://doi.org/10.3390/ani16010146 - 5 Jan 2026
Viewed by 552
Abstract
At Animals Asia’s Vietnam Bear Rescue Center (VBRC), 40% of the current population has been diagnosed with systemic hypertension. Systemic hypertension lesions have led to fatal consequences in the form of aortic aneurysm and rupture. Historically, veterinarians were only able to diagnose systemic [...] Read more.
At Animals Asia’s Vietnam Bear Rescue Center (VBRC), 40% of the current population has been diagnosed with systemic hypertension. Systemic hypertension lesions have led to fatal consequences in the form of aortic aneurysm and rupture. Historically, veterinarians were only able to diagnose systemic hypertension by identifying validated secondary structural heart and retinal lesions during annual health checks of anesthetized bears. In 2021, the VBRC began training bears for cooperative conscious blood pressure measurements to increase monitoring frequency and expedite the diagnosis of systemic hypertension in affected bears. The objective of this study was to evaluate a noninvasive method of blood pressure measurement in trained, cooperative Asiatic black bears. Indirect blood pressure measurements, using the oscillometric technique, were validated with direct arterial measurements in nine bears (6 male, 3 female, ages 13–22 years) undergoing anesthesia for annual health checks. Eleven trained bears at the VBRC without secondary lesions of systemic hypertension (6 male, 5 female, ages 7–23 years) were used to develop normal systolic ranges for Asiatic black bears using the indirect technique. Mean blood pressure measurements for this group of trained bears (n = 11) were 180.65 +/− 37 mmHg (95% CI: 126–255) systolic. These results suggest that indirect blood pressures may be a useful tool to monitor blood pressure in cooperative conscious bears at the VBRC. Full article
(This article belongs to the Section Animal Welfare)
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22 pages, 770 KB  
Article
Law Reforms and Human–Wildlife Conflicts in the Living Communities in a Depopulating Society: A Case Study of Habituated Bear Management in Contemporary Japan
by Satomi Kohyama
Wild 2025, 2(4), 47; https://doi.org/10.3390/wild2040047 - 2 Dec 2025
Cited by 1 | Viewed by 2122
Abstract
Human–wildlife conflicts can be broadly categorized from the perspective of human activities into conflicts (a) caused by the expansion of human activities into wildlife habitats, and (b) resulting from the re-expansion of wildlife habitats due to the decline of human activities. The first [...] Read more.
Human–wildlife conflicts can be broadly categorized from the perspective of human activities into conflicts (a) caused by the expansion of human activities into wildlife habitats, and (b) resulting from the re-expansion of wildlife habitats due to the decline of human activities. The first type of conflict has been managed through the systematic training of wildlife managers, field specialists, and well-organized institutional frameworks. In Japan, Asiatic black bears (Ursus thibetanus) and brown bears (Ursus arctos) have increasingly come into human contact because of habitat re-expansion. Short-term measures to protect human life and property include the implementation of the 2024 and 2025 revisions of the Wildlife Protection and Hunting Management Act, which designated bears as “managed wildlife” and “dangerous wildlife” and permitted emergency culling in residential areas. However, Japan’s approach remains limited in scope and depth, relies on ad hoc responses by local hunters, and lacks adequate public education and effective long-term sustainability planning. This study highlights the necessity of a multi-layered policy framework that integrates human–wildlife conflict management, particularly human–bear conflict, by comparing U.S. laws and policies and incorporating them into medium- and long-term strategies for community resilience and national land conservation. This approach may serve as a model for countries and regions facing similar demographic and ecological challenges. Full article
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24 pages, 9429 KB  
Article
Spatial–Temporal Patterns of Mammal Diversity and Abundance in Three Vegetation Types in a Semi-Arid Landscape in Southeastern Coahuila, Mexico
by Erika J. Cruz-Bazan, Jorge E. Ramírez-Albores, Juan A. Encina-Domínguez, José A. Hernández-Herrera and Eber G. Chavez-Lugo
Diversity 2025, 17(11), 788; https://doi.org/10.3390/d17110788 - 10 Nov 2025
Cited by 1 | Viewed by 1301
Abstract
The grasslands and shrublands of northern and central Mexico cover nearly 25% of the country and harbor high biodiversity. However, they are increasingly degraded by agriculture, urbanization, infrastructure development, and water overexploitation. To assess the status of medium- and large-sized mammals in these [...] Read more.
The grasslands and shrublands of northern and central Mexico cover nearly 25% of the country and harbor high biodiversity. However, they are increasingly degraded by agriculture, urbanization, infrastructure development, and water overexploitation. To assess the status of medium- and large-sized mammals in these threatened ecosystems, we quantified species richness, relative abundance, and naïve occupancy across vegetation types and seasons. From April 2023 to February 2024, monthly track surveys and camera trapping were performed, and the data were analyzed in R. We documented 16 species representing four orders and nine families, with Carnivora being the most diverse (eight species). The species richness varied by habitat, ranging from 11 in montane forest to 13 in semi-desert grassland, the latter habitat having the highest Shannon and Simpson indices, particularly in the dry season. Odocoileus virginianus and Sylvilagus audubonii were consistently the most abundant species in montane forest and desert scrub, whereas Cynomys mexicanus predominated in semi-desert grasslands, accounting for >90% of detections during the rainy season. Rare species included Lynx rufus, Taxidea taxus, and Ursus americanus, each with isolated detections. Rarefaction and sample coverage curves approached asymptotes (>99%), indicating sufficient sampling effort. Naïve occupancy and encounter rates were highest for O. virginianus (0.82) and S. audubonii (0.68), with a strong positive correlation between the two metrics (r2 = 0.92). These findings provide robust baseline information on mammalian diversity, abundance, and habitat associations in semi-arid anthropogenic landscapes, supporting future monitoring and conservation strategies. Full article
(This article belongs to the Special Issue Wildlife in Natural and Altered Environments)
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12 pages, 5800 KB  
Case Report
Bile Duct Stenosis in a Free-Ranging Juvenile American Black Bear (Ursus americanus)
by Taylor Jurgens, Fern Nelson, Wesley Sheley, Alexis Johnson, Liandrie Swanepoel, Seth Wyckoff and Julie D. Sheldon
Animals 2025, 15(21), 3213; https://doi.org/10.3390/ani15213213 - 5 Nov 2025
Viewed by 748
Abstract
A free-ranging 10-month-old male American black bear (Ursus americanus) was presented to a rehabilitation facility in eastern Tennessee for being orphaned and emaciated, and was diagnosed with bile duct stenosis, leading to euthanasia. On initial intake, liver values including gamma-glutamyl transferase, [...] Read more.
A free-ranging 10-month-old male American black bear (Ursus americanus) was presented to a rehabilitation facility in eastern Tennessee for being orphaned and emaciated, and was diagnosed with bile duct stenosis, leading to euthanasia. On initial intake, liver values including gamma-glutamyl transferase, alanine aminotransferase, and serum bile acids were elevated. The cub was treated for intestinal parasites and discharged to a rehabilitation facility for monitoring. Three weeks later, all liver values markedly increased despite improvements in body condition, appetite, and overall energy level. Abdominal ultrasound and dual phase computed tomography confirmed stenosis of the biliary outflow tract with gallbladder dilation and bile ducts in two locations. Surgical treatment and release were not performed due to the lack of clinical follow-up, likelihood of a genetic anomaly, and risk of it being passed to offspring. Necropsy findings further confirmed the bile duct stenosis with chronic regionally extensive fibrosis. The cause of this lesion is hypothesized to be congenital; however, inflammation secondary to a previous infection was not able to be ruled out. This case report documents the presentation and multidisciplinary approach to diagnosing a juvenile bear with bile duct stenosis, not previously reported in the literature. Full article
(This article belongs to the Special Issue Pathology of Wildlife in the Americas)
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32 pages, 6119 KB  
Review
The Brown Bear and Hibernating Mammals as a Translational Model for Human Resilience: Insights for Space Medicine, Critical Care, and Austere Environments
by Jainam Shah, Ryung Lee, Sachin Pathuri, Jason Zheng, Joshua Ong, Alex Suh, Kimia Rezaei, Gagandeep Mudhar, Andrew D. Parsons, Jaewoo Park and Andrew G. Lee
Biology 2025, 14(10), 1434; https://doi.org/10.3390/biology14101434 - 17 Oct 2025
Viewed by 3650
Abstract
Long-term spaceflight induces multisystem stress, including cardiovascular deconditioning, skeletal muscle atrophy, immune suppression, and neuro-ocular syndromes. Current countermeasures reduce symptoms but cannot replicate the synergistic resilience needed for extended missions or critical illness. Hibernating animals, specifically brown bears (Ursus arctos), survive [...] Read more.
Long-term spaceflight induces multisystem stress, including cardiovascular deconditioning, skeletal muscle atrophy, immune suppression, and neuro-ocular syndromes. Current countermeasures reduce symptoms but cannot replicate the synergistic resilience needed for extended missions or critical illness. Hibernating animals, specifically brown bears (Ursus arctos), survive prolonged immobility, starvation, and bradycardia without resultant pathology. This review incorporates adaptations observed in bears and certain torpid species, including reversible insulin resistance, suppression of muscle atrophy genes MuRF1 and Atrogin-1, and maintenance of the heart despite seasonal production decline. The thirteen-lined ground squirrels (Ictidomys tridecemlineatus) maintain retinal structure and synaptic stability throughout torpor, avoiding neuro-ocular complications despite prolonged inactivity. Mechanisms span from RBM3-dependent synaptic maintenance, titin isoform remodeling under the control of RBM20, mTOR and FOXO pathway regulation, remodeled hydrogen sulfide metabolism, and microbiome-mediated nitrogen salvage. These adaptations are different from human adaptation to microgravity and disuse and offer translational candidates for synthetic torpor, probiotic engineering, neuroprotection, and protein-sparing therapy. Hibernators are not passive stress subjects; they perform coordinated anticipatory responses in multiple organs. Comparing these systems in large and small hibernators, we aim to uncover a biologically realistic path to human resilience. These findings guide a shift from reactive, pharmacological measures for preserving human health during space flight, intensive care, and extreme environments towards proactive, biologically initiated measures. Full article
(This article belongs to the Section Physiology)
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16 pages, 265 KB  
Article
Welfare Assessment of Brown Bears (Ursus arctos) in Bulgarian Zoos and Rehabilitation Centres
by Katerina Zareva-Simeonova, Venislava Spasova, Daniela Simeonovska-Nikolova, Krastio Dimitrov, Vladimir Todorov and Kalina Valchinkova
J. Zool. Bot. Gard. 2025, 6(3), 45; https://doi.org/10.3390/jzbg6030045 - 1 Sep 2025
Viewed by 1992
Abstract
Assessing the well-being of captive brown bears is essential for responsible species management and meeting European and national animal care standards outside their natural habitats. The present study aims to assess the welfare of captive brown bears in Bulgaria, considering environmental parameters, husbandry [...] Read more.
Assessing the well-being of captive brown bears is essential for responsible species management and meeting European and national animal care standards outside their natural habitats. The present study aims to assess the welfare of captive brown bears in Bulgaria, considering environmental parameters, husbandry procedures, and the psychological and physical condition of the animals. The study was conducted on 28 brown bears in 11 zoos in Bulgaria and 19 bears in Bear Sanctuary Belitsa. A specific questionnaire and interviews were conducted with zoo managers and keepers. The welfare of the bears was evaluated based on their living conditions, husbandry, and physical and psychological well-being. The Nature and Animal Protection Center in Dobrich received the highest rating for the welfare of two brown bears among the zoos in the study. The study identified annual veterinary check-ups and enrichment programmes as areas needing improvement. Full article
28 pages, 7617 KB  
Article
Using Circuit Theory to Identify Important Ecological Corridors for Large Mammals Between Wildlife Refuges
by Büşra Kalleci and Özkan Evcin
Diversity 2025, 17(8), 542; https://doi.org/10.3390/d17080542 - 1 Aug 2025
Cited by 3 | Viewed by 3943
Abstract
Habitat fragmentation restricts the movement of large mammals across broad landscapes, leading to isolation of individuals or groups, reduced interaction with other species, and limited access to vital resources in surrounding habitats. In this study, we aimed to determine the wildlife ecological corridors [...] Read more.
Habitat fragmentation restricts the movement of large mammals across broad landscapes, leading to isolation of individuals or groups, reduced interaction with other species, and limited access to vital resources in surrounding habitats. In this study, we aimed to determine the wildlife ecological corridors for five large mammals (Ursus arctos, Cervus elaphus, Capreolus capreolus, Sus scrofa, and Canis lupus) between Kastamonu Ilgaz Mountain Wildlife Refuge and Gavurdağı Wildlife Refuge. In the field studies, we used the transect, indirect observation, and camera-trap methods to collect presence data. Maximum Entropy (MaxEnt) (v. 3.4.1) software was used to create habitat suitability models of the target species, which are based on the presence-only data approach. The results indicated that AUC values varied between 0.808 and 0.835, with water sources, stand type, and slope contributing most significantly to model performance. In order to determine wildlife ecological corridors, resistance surface maps were created using the species distribution models (SDMs), and bottleneck areas were determined. The Circuit Theory approach was used to model the connections between ecological corridors. As a result of this study, we developed connectivity models for five large mammals based on Circuit Theory, identified priority wildlife ecological corridors, and evaluated critical connection points between two protected areas, Ilgaz Mountain Wildlife Refuge and Gavurdağı Wildlife Refuge. These findings highlight the essential role of ecological corridors in sustaining landscape-level connectivity and supporting the long-term conservation of wide-ranging species. Full article
(This article belongs to the Special Issue Habitat Assessment and Conservation Strategies)
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