Fecal DNA Methods for Differentiating Grizzly Bears from American Black Bears
Cost effective methods to rapidly confirm the presence of grizzly bears (Ursus arctos) could contribute to their conservation. Although methods to differentiate mitochondrial DNA (mtDNA) of grizzly bears from those of American black bears (U. americanus) have already been published, these require automated sequencing equipment. We present a method using polymerase chain reaction-restriction fragment length […]
Power Analysis of Bait Station Surveys in Idaho and Washington
We evaluated statistical power for detecting trends of specified magnitude in visitation rate for American black bear (Ursus americanus) bait stations in Idaho and Washington. We found evidence for lack of independence due to multiple visits when bait stations were 0.8 km apart and no evidence for this with stations 1.6 km apart. Based on […]
Differential Vulnerability of Black Bears to Trap and Camera Sampling and Resulting Biases in Mark-Recapture Estimates
The accuracy of population estimates derived from mark-recapture sampling will be compromised when marked animals are more or less likely to be recaptured than unmarked animals. We used a ‘test’ population of radiocollared black bears (Ursus americanus) to identify the sources and extent of sampling biases in trapping, camera-trapping, and hunter harvest. We investigated whether […]
Use of Dogs and Mark-Recapture Techniques to Estimate American Black Bear Density in Northeastern Oregon
We estimated black bear (Ursus americanus) population density in the Blue Mountains of northeastern Oregon based on summer mark-recapture surveys in 1996 and 1997. We developed a mark-recapture technique to estimate black bear density using houndsmen with dogs to detect bear scent on driving transects. We conducted 53 surveys and recorded 72 instances where dogs […]
Stimulating Natural Behavior in Captive Bears
Brown bears (Ursus arctos) in zoos are often kept under sub-optimal conditions and have behavioral time-budgets that differ from their wild counterparts. We conducted 2 experiments using novel feeding conditions for captive European brown bears (scattering food rather than piling and increasing feeding frequencies from 3 to 6/day) in the Bear Forest (BF), a 2-ha […]
Grizzly Bear Activity Budget and Pattern in the Firth River Valley, Yukon
I determined the activity of 5 radiocollared grizzly bears (Ursus arctos) in the Firth River Valley, Ivvavik National Park, Yukon, Canada, based on 574 hours of direct observation during 1994 and 1995. Radiocollared grizzly bears that were feeding primarily on caribou (Rangifer tarandus) tended to spend less time feeding and more time traveling or resting […]
Measuring Levels and Patterns of Activity in Black Bears
Incorporation of activity sensors in radiotags provides a mechanism for acquiring activity data on free-ranging bears (Ursus spp.). Tests of sensor sensitivity and correlation of sensor data with known levels of activity are rarely done. We used a surrogate test animal and generated data at 3 levels of activity (rest, walk, and run) from radiocollars […]
Economic Aspects of Large Carnivore-Livestock Conflicts in Romania
In Romania, more large carnivores live near livestock than in any other European country, but little is known about conflicts between the two. Designing a management strategy to preserve livestock protection methods while limiting the economic burden on livestock raisers requires data on (1) organization of livestock raising, (2) cost-income relations of livestock camps, and […]
Black Bear Forest Damage in Washington State, USA: Economic, Ecological, Social Aspects
Black bear (Ursus americanus) damage to coniferous forests can be detrimental to the forest products industry in Washington state. Value of timber damage, west of the Cascade Mountains is millions of dollars every year. The Washington Forest Protection Association’s (WFPA) Animal Damage Control Program (ADCP) manages bear damage in cooperation with the Washington Department of […]
Banff National Park: Science and Policy in Grizzly Bear Management
Grizzly bears (Ursus arctos) in Banff National Park, Canada, and the surrounding ecosystem exist in one of the most developed and politically complex environments where the species persists. Human development and activity have significantly stressed the grizzlies’ population and habitat. The Canadian National Parks Act was amended in 1988 to ensure the ecological integrity of […]
