Bounding the Southern Hudson Bay polar bear subpopulation
Polar bears (Ursus maritimus) are managed by the 5 nations where they occur (Canada, Greenland/Denmark, Norway, Russia, United States) using discrete subpopulations. In Canada, polar bears are harvested throughout their range, and several subpopulations are managed by more than one jurisdiction; therefore, recent management focused on ensuring sustainable polar bear harvests. Consequently, the subpopulation from […]
Density estimation of Asian bears using photographic capture-recapture sampling based on chest marks
Assessing the conservation status of species of concern is greatly aided by unbiased estimates of population size. Population size is one of the primary parameters determining urgency of conservation action, and it provides baseline data against which to measure progress toward recovery. Asiatic black bears (Ursus thibetanus) and sun bears (Helarctos malayanus) are vulnerable to […]
Monograph Series Number 5: A circumpolar monitoring framework for polar bears
Polar bears (Ursus maritimus) occupy remote regions that are characterized by harsh weather and limited access. Polar bear populations can only persist where temporal and spatial availability of sea ice provides adequate access to their marine mammal prey. Observed declines in sea ice availability will continue as long as greenhouse gas concentrations rise. At the […]
A robust-design analysis to estimate American black bear population parameters in Utah
We eveluated the efficiency of an extension of a single season capture-markrecapture (CMR) population estimation method, a closed-capture robust-design model, to monitor trends in population size, apparent survival, and temporary emigration rates over a 5-year period for a low-density population of American black bears (Ursus americanus) in north central Utah, USA. We also used robust-design […]
Demography and mortality patterns of removed brown bears in a heavily exploited population
Harvesting wild animals can affect demographic parameters and life history traits of surviving individuals. Most brown bear (Ursus arctos) populations currently experience low levels of hunting. We characterized mortality patterns in a heavily exploited transboundary brown bear population in Slovenia, Central Europe. Overall, 927 brown bears were reported removed from 1998 to 2008. Most (97%) […]
A case of a brown bear poisoning with carbofuran in Croatia
We provide the first known documentation of a fatal brown bear (Ursus arctos) poisoning with carbofuran (an acetylcholinesterase inhibitor) in Croatia. Diagnosis using liquid chromatographymass spectrometry confirmed the presence of high concentrations of carbofuran in liver and kidney tissue (12.650 and 2.695 ppm, respectively). These measurements, combined with the very small distance between poisonous baits […]
Factors affecting habitat patch use by sloth bears in Mudumalai Tiger Reserve, Western Ghats, India
Of the threats facing sloth bear (Melursus ursinus) populations, habitat fragmentation is the most pressing. Although conservation requires protection of habitat, little is known about the factors governing sloth bear occurrence. We used camera-trapping data to investigate occupancy of sloth bears in Mudumalai Tiger Reserve, an important conservation site in India during January-April 2010. Presence-absence […]
Potential distribution of American black bears in northwest Mexico and implications for their conservation
Defining areas of potential distribution for large carnivores is a critical step for generating conservation strategies. Ecological niche modelling is an important tool for identifying potential areas for conservation of carnivores, such as American black bears (Ursus americanus) in the Sierra Madre Occidental (SMOcc) and the Sky Islands (SI) region of Northwest Mexico. Our objective […]
Myrmecophagy of Japanese black bears in the grasslands of the Ashio area, Nikko National Park, Japan
Ants are an important food resource for most of bear species. During the summer, Japanese black bears (Ursus thibetanus japonicus) use grasslands in the 60 km² Ashio area as an ant feeding site. We studied levels of myrmecophagy using GPS locations and activity sensor information along with direct observations of 2 bears during 2004 and […]
Temporal sampling frame selection in DNA-based capture-mark-recapture investigations
Capture-mark-recapture (CMR) population parameter estimation utilizing DNA analysis from remotely-collected hair samples to identify individuals and generate encounter histories has become the standard methodology for estimating abundance of American black (Ursus americanus) and grizzly bear (U. arctos) populations. However, few published studies have examined the time frame for efficiently collecting high-quality hair samples. Our objectives […]
