The Role of American Black Bears and Brown Bears as Predators on Ungulates in North America
American black bears (Ursus americanus) and brown bears (U. arctos) can be important predators on neonatal ungulates. They prey less commonly on adult ungulates. Bear predation appears to be additive at low ungulate densities and may become compensatory as prey density approaches carrying capacity, K. As such, black and brown bear predation can limit, but […]
Tube Traps and Rubber Padded Snares for Capturing American Black Bears
American black bears (Ursus americanus) are commonly captured for research purposes with Aldridge traps. Disadvantages of this method include the possibility of non-target species setting off traps or being captured, a lengthy installation time, the possibility of bears being captured by the toes, and hind-foot captures. Here, we describe the RL04 trap, used with rubber-padded […]
Education Programs for Reducing American Black Bear-Human Conflict: Indicators of Success?
Education programs designed to reduce conflicts between American black bears (Ursus americanus) and humans are often implemented by diverse groups of wildlife practitioners who may devote significant resources to these programs, yet little has been done to characterize the content, structure, and effectiveness of these programs. We review 6 education programs in North America. We […]
Brown Bear Predation on Domestic Sheep in Central Norway
In 1994, we studied predation on domestic sheep using mortality radiocollars in an area in central Norway inhabited by brown bears (Ursus arctos). The total loss among 234 radiocollared ewes in 3 herds released on summer pastures was 54, and 51 (94.4%) were due to bear predation. Among 337 radiocollared lambs, 37 were known to […]
Distribution of Grizzly Bears in the Greater Yellowstone Ecosystem in 2004
The US Fish and Wildlife Service (USFWS) proposed delisting the Yellowstone grizzly bear (Ursus arctos horribilis) in November 2005. Part of that process required knowledge of the most current distribution of the species. Here, we update an earlier estimate of occupied range (1990-2000) with data through 2004. We used kernel estimators to develop distribution maps […]
Characteristics of Polar Bears Killed in Defense of Life and Property in Nunavut, Canada, 1970-2000
Canada’s newest territory, Nunavut, has experienced increasing human population and growing resource extraction and exploration activities. Interactions between polar bears (Ursus maritimus) and humans are very likely to increase in the future, and knowing where, when, and why they occur could aid in preventing these events. I examined age, sex, time of year, general location, […]
Influence of Phenology on Site Selection by Female American Black Bears in Coastal British Columbia
We examined factors that affect site selection by female American black bears (Ursus americanus) in coastal British Columbia, Canada, 1992-95. We monitored 9 radiocollared females and compared sites that were selected within their home ranges to those that were not selected using 1-1 matched logistic regression procedures. We used information-theoretic inference to assess the effect […]
Activity Patterns of American Black Bears in Yosemite National Park
The impacts of tourism, most notably food resource enrichment and harassment, have led to alterations in natural bear (Ursus sp.) behavior in many National Parks throughout the United States. Comprehensive efforts to reduce these impacts and restore natural activity patterns have been elements of US National Park management for decades. We described black bear (U. […]
Reproduction and Survival of Brown Bears in Southwest Alaska, USA
From June 1993 to June 2003, 40 adult female brown bears (Ursus arctos) were captured, radiocollared, and tracked for 1 to 10 years in a previously unstudied population in southwest Alaska. Mean litter size upon emergence from dens was 2.0, decreasing to 1.5 at weaning. Mean age of offspring at weaning was 2.9. Mean age […]
Andean Bear-Livestock Conflicts: A Review
We review the state of knowledge regarding conflicts between the Andean bear (Tremarctos ornatus) and livestock. Information was gathered from the current known geographic range of the species (Venezuela, Colombia, Ecuador, Peru, and Bolivia). Andean bears are perceived as livestock predators where herding is common; bears are frequently blamed for any livestock disappearance or death. […]