The Greater Yellowstone Ecosystem (GYE) supports the southernmost of the 2 largest remaining grizzly bear (Ursus arctos) populations in the contiguous United States. Since the mid-1980s, this population has increased in numbers and expanded in range. However, concerns for its long-term genetic health remain because of its presumed continued isolation. To test the power of genetic methods for detecting immigrants, we generated 16-locus microsatellite genotypes for 424 individual grizzly bears sampled in the GYE during 1983–2007. Genotyping success was high (90%) and varied by sample type, with poorest success (40%) for hair collected from mortalities found ≥1 day after death. Years of storage did not affect genotyping success. Observed heterozygosity was 0.60, with a mean of 5.2 alleles/marker. We used factorial correspondence analysis (Program GENETIX) and Bayesian clustering (Program STRUCTURE) to compare 424 GYE genotypes with 601 existing genotypes from grizzly bears sampled in the Northern Continental Divide Ecosystem (NCDE) (F_ST  =  0.096 between GYE and NCDE). These methods correctly classified all sampled individuals to their population of origin, providing no evidence of natural movement between the GYE and NCDE. Analysis of 500 simulated first-generation crosses suggested that over 95% of such bears would also be detectable using our 16-locus data set. Our approach provides a practical method for detecting immigration in the GYE grizzly population. We discuss estimates for the proportion of the GYE population sampled and prospects for natural immigration into the GYE.

Sex and age composition of harvested individuals often is used to estimate population parameters and inform management decisions. However, factors other than sex and age structure of the harvested population may affect composition of the harvest and complicate the interpretation of harvest data. For example, class-specific behavior could predispose certain age and sex classes to harvest. Those classes also may respond differentially to environmental variables such as natural food abundance. In addition, hunter methods such as baiting or hunting with dogs are known to alter the composition of harvests of American black bears (Ursus americanus) and influence hunter success. Bear hunting methods and general habitat characteristics vary geographically in Wisconsin, USA. From 1999 through 2004, bear hunting was regulated so that first season hunting opportunities alternated annually between hunters aided by dogs and hunters without dogs in portions of 21 northern counties. Bear hunting with dogs was prohibited in the remainder of the state. We analyzed bear harvest records from those 6 years to evaluate relative effects of forest cover, forest composition, and legal hunting methods on sex and age composition of harvested bears. With other variables held constant, mean age of harvested female bears was 0.6 years older in counties that were partially open to hunting bears with dogs. Countywide allowance of hunting with dogs equated to a 1.3 year increase in the mean age of harvested female bears over counties where the use of dogs was not permitted. A 20% increase in area of potentially mast-producing forests was associated with a 0.7 year decrease in mean age of harvested females. Mean age of harvested male bears was 0.3 years higher when hunters with dogs hunted after hunters without dogs. Finally, males comprised higher percents of harvests in counties with less total forest cover or greater mast-type forest cover when other variables were held constant. Our study suggests that variation in hunting method and habitat influenced harvest outcomes at a broad spatial scale and warrant consideration when interpreting patterns in sex and age structure of black bear harvests.

Use of habitat and resources of large carnivores living at the expansion front of a population can differ considerably from those living in core areas. Using GPS (global positioning system) telemetry, we studied movements of male brown bears living in the northwest edge of the Alpine–Dinaric–Pindos population in Slovenia and Italy, 2005–08. Because there was a steep gradient of female densities in the periphery of the population and females occurred only in a small portion of the area used by males, we could test how the distribution of breeding females affected the spatial distribution and movements of male brown bears. The home-range size of the males in our study was inversely related to female densities. During the mating season we observed directed movement from the periphery of the population with low female densities toward the core area with higher female densities. Our observations suggest that this strategy allows even males living at the periphery of the population, where no females were know to occur, to take part in reproduction.

Regulated hunts of carnivores are believed to prevent property damage and other conflicts with people. Few studies have tested if public hunting reduces subsequent complaints about carnivores. We analyzed 10 years of data on nuisance complaints from a hunted American black bear (Ursus americanus) population in Wisconsin, USA. At the statewide scale, complaints about agricultural damage, other property damage, or human safety concerns did not correlate with each other or with number of bears taken by hunters in the preceding 1–2 years. At the smaller scale of bear management zones, there were positive correlations between the number of bears taken by hunters in one year and all categories of nuisance complaints in subsequent years. Once corrected for the estimated bear population size, only property damage retained a significant positive correlation with hunter take in prior years. Age and sex profiles of bears taken by hunters differed significantly from those of bears live-trapped around sites of nuisance complaints. Hunters took significantly younger bears and a lower proportion of males. The most common method (shooting over bait) produced age–sex profiles most different from bears live-trapped after nuisance complaints. Although hunters removed 356 bears implicated in nuisance complaints, they took these bears in proportion to their availability. We conclude that the Wisconsin bear-hunting season did not show clear evidence of reducing nuisance complaints during 1995–2004, probably because hunting was not effectively designed for that goal. We call for additional research on hunter and bear behavior, including experimental tests of hunting individuals with different levels of involvement in property damage.

Resource extraction activities in Alberta, Canada, have produced a large increase in the number of roads in grizzly bear (Ursus arctos) habitat. High road densities have been associated with high grizzly bear mortality rates in some areas. We used GPS data from grizzly bears in west-central Alberta, Canada, 1999–2005 to examine (1) frequencies at which grizzly bears crossed roads (standardized by number of locations/bear and length of road segments), using a crossing index analysis among age–sex classes, traffic volumes, seasons, and time of day; (2) habitat attributes surrounding crossing locations, using a resource selection function analysis to discern if certain habitats and road types were associated with crossing areas; and (3) grizzly bear distribution near roads as a function of age–sex class and season to determine if bears were near roads more or less frequently than expected. Females had higher crossing indices than males for all seasons and daylight hours. Crossings occurred most often at narrow, unpaved roads near creeks and in open areas with high greenness scores. In spring, females with cubs were within 200 m of roads more frequently than expected. In autumn, subadult females were within 200 m of roads more frequently than expected, whereas adult males displayed the reverse pattern. These results indicate that females had a greater chance of encountering humans. Reducing the density of roads in grizzly bear habitat or reducing human presence on these roads, especially during the spring and fall seasons, may reduce the human-caused mortality to female grizzly bears. Creating or leaving a dense tree buffer along roads that traverse open habitats could provide a visual shield from passing vehicles, which may reduce grizzly bear–human encounters and human-caused mortalities.

Since 1990, increases in American black bear (Ursus americanus) population and distribution in the Lower Peninsula of Michigan, USA, have led to positive trends in black bear harvests, sightings, and nuisance reports. Policy makers and wildlife managers can prepare for the difficult task of managing future bear–human interactions by using resource selection models to assess bear habitat selection and predict future bear range expansion. We modeled habitat selection by black bears in the northern Lower Peninsula of Michigan using 6 environmental variables based on radiotelemetry locations from 1991–2000 for 20 males and 35 females. We developed Bayesian random effects discrete-choice models for males and females separately to estimate probability of bear selection of grid cells at 3 spatial resolutions (1 km², 4 km², 9 km²). These models weight individual bears and their relocations, allowing inference about both individual and population-level selection characteristics. We assessed goodness-of-fit of individual models using a Bayesian P value that estimated deviance between a simulated dataset and the observed dataset. Models for males at the 9-km² resolution and for females at 4-km² resolution fit our data better than others; both indicated that locations of bears were negatively associated with water, small and medium roads, mean patch size, patch size coefficient of variation, edge density, developed land-use, and non-forested wetlands, and positively associated with Shannon's diversity index, aspen (Populus spp.), and forested wetlands. Furthermore, the variability in selection by individual female bears for non-forested wetland and individual male bears for agriculture was large relative to the variability in selection of other land-use or land-cover types. Male bears had more heterogeneity with respect to selection of land-use or land-cover types than female bears. There were significant correlations between male bear age and their respective selection parameter estimates for small roads, medium roads, and developed land-use. Running Bayesian random effects discrete-choice models at multiple resolutions accounted for variability due to unequal sample sizes and bear behavior, and demonstrate the utility of the Bayesian framework for bear management purposes.

The Japanese black bear (Ursus thibetanus japonicus) causes serious and persistent damage to conifer plantations in some areas of Japan. From 2006–08, we examined bear damage and tree characteristics (diameter at breast height [DBH], width of growth rings, and amount and nutritional content of newly-developing vascular tissues) in 7 even-aged stands of Japanese cypress (Chamaecyparis obtusa) growing at similar elevations in a university forest. Larger-diameter trees were more likely than smaller trees to be damaged by bears in each stand. The major nutritional component of vascular tissues was sugar, mainly sucrose. Sugar concentration of vascular tissues showed little variation, and was correlated with neither DBH nor stand age. Mass of vascular tissues was highly variable and was positively correlated with DBH, but not with stand age. To reduce bear damage, foresters should concentrate direct protection efforts on larger-diameter trees.

Asiatic black bears (Ursus thibetanus) are threatened by habitat loss and poaching, especially in the tropical portions of their range; reserves serve a crucial role in conserving this species. Yet data on spatial and habitat requirements for this species in tropical areas, necessary for assessing the efficacy of reserves, is virtually nonexistent. We used mainly ground-based telemetry to investigate home range sizes of the endangered Formosan subspecies (U. t. formosanus) in the largest park in Taiwan. The largest observed home range (117 km²) was an adult female with a satellite radiocollar. Normally, male bears have significantly larger home ranges, but males tracked with ground telemetry often could not be located due to the rugged terrain and limited accessibility of our study area, so their home ranges were underestimated. This is a common, but often neglected problem of telemetry studies in protected areas with difficult human access. Although elevations ranged from 300 to >3,500 m, bears mainly used areas below 2,000 m, selecting broadleaved and mixed broadleaved–coniferous forests. Production of acorns (Cyclobalanopsis and Quercus), a sought-after fall food, varied yearly. One site in the interior of the park produced an abundance of acorns in some years, attracting a dense congregation of bears; however, females and subadult males were socially excluded. Despite limitations of our telemetry data, we observed that half the bears, all caught near the center of the park, traveled beyond the boundaries where they were more vulnerable to illegal hunting, suggesting that more protection is needed along the edges of the park.

I summarize data on the brown bear (Ursus arctos) in the South Caucasus, which includes Armenia, Azerbaijan, and Georgia. The most current information is from Georgia, where research has been carried out on the species. I determined the present distribution of brown bears in the South Caucasus based on extensive fieldwork, literature, and satellite maps. Bears have been exterminated from many areas and now live mainly in mountain forests, where human access is limited. In some areas of the South Caucasus, the bear range may be considered fragmented. The many population estimates have varying credibility among countries and periods. I estimate that 2,000–2,500 bears remain in the South Caucasus. The brown bear is protected in Georgia and Armenia and is hunted legally in Azerbaijan. Scientists from the South Caucasus agree that recreational, illegal hunting is the primary problem in the region.

The brown bear (Ursus arctos) population in the Cantabrian Mountains of northwest Spain is among the most endangered bear populations worldwide. It is divided into 2 isolated and genetically differentiated subpopulations. We present evidence of recent male migration between the subpopulations based on genetic identification of hair and scats samples gathered between 2004 and 2007. Of 76 identified individuals, our analysis assigned 3 males sampled in the eastern subpopulation to the western subpopulation. As well, 1 male genetically belonging to the eastern subpopulation was repeatedly sampled along his way to the western subpopulation during April to November 2006 (a linear distance of 144 km). This bear's path may help identify natural corridors, which could be improved through restoration management. In addition, we identified 2 genetically admixed individuals during 2008 in the Western limit of the eastern subpopulation range. Connectivity between subpopulations and gene flow appears to be improving after a long isolation.

Although brown bears (Ursus arctos) are rare in the Himalayan region, populations have been documented in alpine habitats of Pakistan and India. Brown bears were once known to exist in both Nepal and Bhutan, but current information on their numbers and distributions was lacking. We document the presence of brown bears in the Manasalu Conservation Area (MCA) in Nepal using field surveys and interviews with local people. We were able to confirm the existence of a remnant population based on finding bear scat and locations where bears excavated for Himalayan marmots (Marmota himalayana). Based on interviews with local people, it appeared that the presence of brown bears in the area is relatively recent and likely a result of immigration of bears from the Tibetan Autonomous Region. Interviews with local herders also indicated that livestock losses from brown bear predation amounted to approximately 318,000 Nepali rupees (US $4,240) from February 2006 through July 2008.

We collected blood samples (n  =  49) from 43 Andean Bears (Tremarctos ornatus) in Ecuador between September 1995 and May 2006 and analyzed them for 11 serum biochemical and 13 hematological parameters. Results were grouped and compared according to the bears' life condition (captive or free-ranging), sex, age, and body mass. Free-ranging bears had higher serum glucose and monocyte levels than captive bears, but slightly lower mean cellular hemoglobin concentrations. Male bears had higher serum protein levels than female bears. Adult bears showed higher levels of cholesterol, hematocrit, and hemoglobin than sub-adult bears. In contrast, alkaline phosphatase and phosphorous levels were higher in sub-adult bears. Bears with a body mass >80 kg had higher levels of serum proteins and blood urea nitrogen than lighter-weight bears. Plasma triglyceride levels observed in this study were very high in relation to those reported for other bear species. Alkaline phosphatase levels were also high in comparison to those of other bear species, except the giant panda (Ailuropoda melanoleuca). Observed mean values for glutamic pyruvic transaminase, glutamic oxalic transaminase, glucose, and calcium were low in this study relative to those of captive Andean bears from other countries, whereas the mean alkaline phosphatase value was comparatively high. Mean values for glutamic pyruvic transaminase, glutamic oxalic transaminase, glucose, calcium, mean cellular hemoglobin, and mean cellular volume were lower relative to other bear species. The data presented in this paper will provide baseline reference values that may prove useful in the diagnosis of disease and assessment of nutrition in wild and captive Andean bears.

The Cantabrian brown bear (Ursus arctos) population of northwest Spain has been monitored since 1982. Population trends have been estimated using counts of females with cubs-of-the-year (hereafter, F_CUB). A population viability analysis found a mean annual decrease of 4–5% for 1982–95, but with a stabilizing or even slightly increasing trend in the early 1990s. A recent paper in Ursus concluded that the population was “recovering,” with a 7.5% annual increase, based on the F_CUB index for 1994–2004. We show several factors limit the interpretation of an increasing trend based on the F_CUB data. First, data collection was not systematic, nor were spatial sampling and sampling effort sufficiently accounted for, leading to an arbitrary election of the period to estimate F_CUB trends. Second, data sets did not meet probabilistic analytical requirements. Third, the assumption that the F_CUB trend, albeit positive, directly reflects the population trend was not justified. In addition, we argue that alternative hypotheses explaining F_CUB trends should have been presented, particularly because of the absence of a correlation between population and range increases. Altogether, we call for caution when analyzing data about critically endangered populations like that of brown bears in the Cantabrian Mountains.

We reply to the critique from Fernández-Gil et al. (2010) regarding our study on trends in female brown bears with cubs (F_CUB) in the Cantabrian Mountains, Spain (Palomero et al. 2007). We discuss the relationship between sampling effort and the number of F_CUB, the methods used to collect the data, and the relationship between the F_CUB and the whole bear population.