Demography and Population Trend of Grizzly Bears in the Swan Mountains, Montana

• Published in: Conservation Biology
• Main Authors: Mace, Richard D., Waller, John S.
• Format: Article in Journal/Newspaper
• Language: English
• Published: Wiley 1998
• Subjects: Ursus arctos
• Online Access: http://dx.doi.org/10.1046/j.1523-1739.1998.97031.x; http://api.wiley.com/onlinelibrary/tdm/v1/articles/10.1046%2Fj.1523-1739.1998.97031.x; http://onlinelibrary.wiley.com/wol1/doi/10.1046/j.1523-1739.1998.97031.x/fullpdf

From 1987 to 1996 we used capture and telemetry methods to study the demography, movements, and population trend of grizzly bears ( Ursus arctos horribilis ) in wilderness and nonwilderness portions of the Swan Mountains of Montana. Most data were collected in the nonwilderness portion, which included public multiple‐use lands and rural areas on and near private lands. Population density in nonwilderness averaged 1.6 bears/100 km 2 . The annual total mortality rate (13.4%) was higher than that found in expanding brown bear ( Ursus arctos ) populations. A tenuous finite rate of increase (λ) of 0.977 (95% CI = 0.875–1.046) was related to high female mortality. Annual mortality rates for bears utilizing the rural and wilderness zones was 21 and 15 times higher, respectively, than for bears using only multiple‐use lands. Our mortality, movement, and occupancy data suggest that the multiple‐use zone is a population source area, and that wilderness and rural zones are sink areas. Mortalities in the wilderness zone were from mistaken identification during the black bear ( Ursus americanus ) hunting season and human defense of life. In the rural zone, mortalities were from malicious killing and the management removal of habituated or food‐conditioned bears. We recommend that wildlife managers develop a conservation strategy to promote bear population stability or growth by improving female survival while minimizing bear conflicts on private lands. This would be accomplished by protecting core areas on public lands of superior habitat through access management, conducting a mandatory bear identification course for black bear hunters, and reducing anthropogenic foods on private lands. We also recommend a continuing population and habitat monitoring program. Demografia y Tendencias del Oso Grizzly en las Montañas Swan, Montana De 1987 a 1996 utilizamos métodos de captura y telemetría para estudiar la demografa, movimientos y tendencias de los osos grizzly ( Ursus arctos horribilis ) en porciones silvestres y no‐silvestres ...