Population characteristics and the effects of hunting on black bears in a portion of northwestern Montana.

摘要: Thier, Timothy J., M.S., August 1990 Environmental studies Population Characteristics and the Effects of Hunting on Black Bears in a Portion Northwestern Montana (100 pp.) Directors: Thomas Roy Bart W. O'Gara I\/t, ~ Prior information regarding status black bears (Ursus americanus) District 100 extreme northwestern was confusing oftentimes conflicting. To gather population effects hunting, especially during spring hunting season, 13 were radio-collared monitored 1986 1987. An additional 15 marked released. Information gathered age sex structure capture sample, survival mortality rates bears, reproduction, home range sizes, hunter technique effort. A density estimate 1 bear/15.4 km for study area determined. The captured comprised primarily adult males, which is generally recognized as indicative lightly or unexploited population. However, due to found excessive. decrease number from 1987, large proportion killed, 1987 observation data, all indicate that well sampled by trapping. reproductive rate 0.70 cubs/female/year determined, with at least female not producing successful litter until 7. mean size males (5+ years) using minimum convex polygon method 98.7 35.5 192.6 (n ;: 7). females 45.8 17.5 107.4 = 4). Driving open roads primary used season. Thirty-nine percent killed season shot within m an road, while 66% after first being observed road.