Home Range and Movements of Female Brown Bears in Southwestern Alaska
Between 1993 and 2003, 40 adult female brown bears (Ursus arctos) were radiocollared and monitored in the southwest Kuskokwim Mountains of Alaska. The 95% kernel home range size for individuals with ≥50 relocations (n = 20) ranged from 93-623 km2 (x̄ = 356 km2). Bears occupied lower elevations during July and August (x̄ = 454 […]
Changing Numbers of Spawning Cutthroat Trout in Tributary Streams of Yellowstone Lake and Estimates of Grizzly Bears Visiting Streams from DNA
Spawning Yellowstone cutthroat trout (Oncorhynchus clarki) provide a source of highly digestible energy for grizzly bears (Ursus arctos) that visit tributary streams to Yellowstone Lake during the spring and early summer. During 1985-87, research documented grizzly bears fishing on 61% of the 124 tributary streams to the lake. Using track measurements, it was estimated that […]
Survival, Cause-Specific Mortality, Sex, and Ages of American Black Bears in Washington State, USA
Wildlife managers often rely on data from hunter-harvested animals for monitoring structural and numerical changes of hunted animal populations, including American black bears (Ursus americanus). Some analyses of hunter-harvested animals assume that sex and age data from harvested animals accurately reflect the demographic structure of the population. We compared sex and age structure from black […]
Sexually Selected Infanticide in Grizzly Bears: The Effects of Hunting on Cub Survival
Sexually selected infanticide (SSI) has been documented in some species with a mating system in which males have almost exclusive breeding rights with 1 or more females. When the dominant male is removed, the new male kills the offspring sired by the previous male to enable the mother to be bred earlier. It has been […]
Human-Sun Bear Conflicts in East Kalimantan, Indonesian Borneo
Interviews with farmers (1998-2000) in 5 communities along the edge of the Sungai Wain Protection Forest, East Kalimantan, Indonesian Borneo, indicated that crop damage caused by sun bears (Helarctos malayanus) was higher than normal following the 1997-98 El Niño Southern Oscillation Event. Widespread drought and forest fires reduced habitat and fruit availability for sun bears […]
Natural Landscape Features, Human-Related Attractants, and Conflict Hotspots: A Spatial Analysis of Human-Grizzly Bear Conflicts
There is a long history of conflict in the western United States between humans and grizzly bears (Ursus arctos) involving agricultural attractants. However, little is known about the spatial dimensions of this conflict and the relative importance of different attractants. This study was undertaken to better understand the spatial and functional components of conflict between […]
Andean Bear Management Needs and Interactions with Humans in Colombia
Andean bears (Tremarctos ornatus) in Colombia face serious threats, including hunting, habitat loss, and bear-human interactions. Interactions are increasing, but data about these encounters are not consistently compiled. Likewise, bear management needs have not been evaluated. Solutions to these threats and needs are complex and will depend upon biological as well as cultural and political […]
To Weigh or Not to Weigh: Conditions for the Estimation of Body Mass by Morphometry
The objective of this study was to define the conditions under which the body mass of polar bears (Ursus maritimus) can be estimated by morphometry with acceptable accuracy (high precision and low bias). Morphometric and body mass values from 563 polar bears captured and handled in southern Hudson Bay during 1984-86 and 2000-03 were analyzed […]
Estimation of Feeding History by Measuring Carbon and Nitrogen Stable Isotope Ratios in Hair of Asiatic Black Bears
To investigate feeding habits, carbon and nitrogen stable isotope ratios were measured in hair sampled from Asiatic black bears (Ursus thibetanus) inhabiting an alpine area, including the Northern Japanese Alps and the periphery of villages in Nagano Prefecture, in central Japan. Asiatic black bears in the Northern Japanese Alps are subject to little human influence, […]
American Black Bear Population Size and Genetic Diversity at Apostle Islands National Lakeshore
Effective management of American black bears (Ursus americanus) requires an understanding of population demographics. In 2002, we obtained DNA from hair collected at barbed-wire traps to estimate black bear population size and study population genetics on Stockton (4,069 ha) and Sand (1,193 ha) islands at Apostle Islands National Lakeshore (AINL), Wisconsin. Hair samples also were […]