Grizzly bear (Ursus arctos) populations are costly to monitor by traditional survey methods. In British Columbia, Canada, hunter kill data are available and provide relatively inexpensive information that possibly can be used to estimate trends in hunted populations. We applied statistical population reconstruction (SPR) using Program PopRecon 2.0 to evaluate trends in abundance of ≥3-year-old male grizzly bears for 3 large areas in British Columbia. Model inputs included annual estimates of age-at-kill and hunter effort, combined with auxiliary information on population abundance in 2012, and a non-hunting survival rate. Modeled abundance in all 3 areas was sensitive to the auxiliary abundance estimate but less so for the auxiliary survival estimate or the length of the time series. Relative trends in abundance appeared to be primarily affected by kill and effort data and were less affected by the auxiliary data. The gradual increase in abundance within the Temperate Mountains area from 1985 to 2004 followed by an apparent decline was consistent with other independent studies and supported the premise that grizzly bear numbers were recovering from a population low until between 2000 and 2005. Our results suggest that the grizzly bear population in the Boreal–Sub-boreal area was also recovering during this period. Our analysis demonstrates the potential utility of SPR for monitoring grizzly bear population trends, but results from the Coastal area also highlight the importance of sufficient hunter-kill and -effort data, in addition to quality auxiliary data, to detect population change. Future enhancements in Program PopRecon may help improve the performance and utility of SPR for grizzly bears in British Columbia.

Large carnivores are among the most threatened species in the world because of their natural low densities and need for expansive habitats. The brown bear (Ursus arctos) is the largest carnivore in the southwestern Asia, and faces threats in much of its range from conflict with humans over shared resources and shrinkage of habitat. In this study, we surveyed for brown bear sign and scat during spring–autumn from April 2013 to November 2015 in 24 randomly selected, 25-km² grid cells, and developed a model of potential brown bear occurrence in one of its globally southernmost distribution ranges in Iran. To better understand its conservation needs and management priorities at the landscape scale, we used a combination of field surveys to develop a Maximum Entropy (Maxent) model. The model was developed using 10 environmental and anthropogenic predictors. Potential brown bear occurrence was strongly influenced by availability of water resources (54.1%) as the most important variable; and distance to roads (16.1%), aspect (7.6%), and vegetation types (5.9%) were the other important factors. The model showed an area of 581 km² (35%) within the study area has high to good bear-occurrence probability values; 86% of this area is located in 2 patches, each larger than the average bear home range. Identification of these patches may support establishment of a reserve in the area, which would ensure long-term survival of the brown bear and sustainable water use and resource extraction from Pistacia atlantica forests by resident and nomadic communities in the region.

Selection of den sites is a crucial aspect of American black bear (Ursus americanus) life history. High-quality dens provide thermal insulation, protection from disturbance, suitable environment for parturition and cub development, and proximity to available forage upon emergence. Black bears are increasingly coexisting with people in human-dominated landscapes; however, little is known about whether urban environments influence characteristics of dens and den site selection. Our objective was to determine the effect of housing density (a proxy for human activity and availability of anthropogenic resources) on selection of den sites in years of good and poor natural forage. We additionally compared size, shape, and location of dens of males and females to describe den characteristics and explore whether differences existed between males and females. We revisited 34 den locations detected during a 6-year (2005–2010) urban black bear study in Aspen, Colorado, USA, and measured den entrance and den volume. We fit a conditional logistic regression model using a resource selection function framework to determine the importance of housing density and other landscape variables (elevation, slope, aspect, and vegetation type) associated with den site selection. Slope was the best predictor of den site selection and there was no relationship between den selection and housing density, indicating that black bears were neither avoiding nor seeking urban areas for denning. Dens were smaller for females ( = 3.30 m³, SE = 1.94, n = 22) than for males ( = 7.56 m³, SE = 3.31, n = 8), supporting the idea that females have greater constraints in den characteristics, possibly related to cub development and security from predation or because females generally are smaller than males.

Applying an integrative approach incorporating attitudes toward wildlife in general and toward a specific species (American black bear [Ursus americanus]) can help land managers make decisions about the complex issue of human–bear interactions. The purpose of our study was to (1) assess park visitors’ attitudes toward wildlife, black bears, and possible management actions related to black bears in a park setting; (2) identify the impact of general attitudes toward wildlife and specific attitudes toward black bear on park visitors’ support for various black bear management actions; and (3) to examine whether visitor demographics affect their support for management actions. From March through September 2013, 364 visitors to the Big South Fork National River and Recreation Area (a unit of the U.S. National Park Service located in the southeastern United States) completed a survey, resulting in a 72% response rate. Park visitors generally expressed a positive attitude toward wildlife education and enjoyment of seeing wildlife, while they were more polarized on the importance of wildlife management and their appreciation of wildlife through hunting. Hierarchical regression analyses indicated that park visitors’ attitudes were better predictors of support for management than were their demographic characteristics. Park visitors who agreed that “people appreciate wildlife through hunting” and “bears are a threat to people” were likely to accept lethal management actions. Their attitudes toward hunting in general were the most significant predictors of acceptance of lethal management actions. Park visitors’ positive attitudes toward black bear conservation and acceptance of the current number of black bears in the park were predictors of their acceptance of non-lethal management actions. The number of human–bear interactions in the park currently is small; and this proactive study expands possible management options with the intent of preventing and minimizing human–bear conflicts in a protected area where people recreate and wildlife coexists.

Few studies have analyzed the genetics of Andean bear (Tremarctos ornatus) populations through the use of the hypervariable D-Loop mitochondrial region. This approach can be useful for the assessment of genetic diversity and ancestral lineages. In the present study we evaluate the genetic status of an Andean bear population in northern Ecuador using D-loop mtDNA sequence polymorphisms. For this purpose, DNA from individuals sampled in the Metropolitan District of Quito was used to amplify and sequence a fragment of the hypervariable D-loop region. Our results show remarkably low levels of genetic diversity, based on haplotype (H) and nucleotide (π) diversity indices, and low pairwise genetic distances between haplotypes. Phylogenetic analyses suggest that these haplotypes are clustered into a single monophyletic group. These diversity indices are among the lowest reported for any bear population, suggesting a need to establish or revise the current conservation strategies in the region.

Grizzly bears (Ursus arctos) are omnivore generalists that eat a wide array of plants and animals, including insects. Human-induced changes in climate may affect the species composition, abundance, range, and elevational distribution of the plants and animals consumed by grizzly bears. Therefore, determining the current food habits of grizzly bears is important for documenting future changes in food resources and how those changes may affect the nutritional ecology of grizzlies. In 2011, we observed grizzly bears in Yellowstone National Park (YNP) eating midges from the family Chironomidae along the shoreline of Yellowstone Lake. Midges are small, swarming aquatic insects that occasionally wash ashore in large numbers around the lake. To our knowledge, grizzly bear consumption of midges had not previously been reported in YNP despite extensive bear food-habits studies conducted there. We believe that midges are likely an opportunistic food for grizzlies, eaten only during sporadic periods of super-abundance.

To advance our knowledge on the rubbing behavior of Andean bears (Tremarctos ornatus), we assessed characteristics of their rub-trees in the Peruvian tropical dry forest, where water is a rare and critical resource. We registered characteristics of rubbed and unrubbed trees and shrubs along bear trails in an area of approximately 100 km² surrounding 7 waterholes in the western Andes foothills of Peru during austral summer 2014–2015. Analysis of 94 trees selected for rubbing (hereafter, rub-trees) and 253 available unmarked trees within a 5-m radius of each rub-tree showed that bears selected trees to rub that were relatively small and close to waterholes. Bears seemed to avoid the most common tree species, palo santo (Bursera graveolens), for tree-rubbing. We suggest that waterholes are important habitat features for Andean bears in the Peruvian dry forest, and that these sites be incorporated into conservation and land use management.

Once common throughout the Indian subcontinent, the sloth bear (Melursus ursinus) is restricted to certain areas and is classified as vulnerable by the International Union for Conservation of Nature. Habitat loss and fragmentation is the primary reason for population decline, but there is a dearth of information about the effects of fragmentation on connectivity and genetic variation. Non-invasive DNA samples are commonly used to investigate connectivity and monitor populations in the wild. We developed a polymerase chain reaction (PCR) –based technique to identify sloth bears from non-invasively collected samples. Three sets of primers were designed to amplify short fragments of mitochondrial DNA to reduce false negatives, which is an issue with non-invasively collected DNA. The PCR success rate in both fresh and dry samples was high (88%). Failure to amplify DNA from other co-occurring mammals confirmed species specificity. This approach provides an efficient method to identify sloth bear samples using non-invasively collected DNA.