Demographics and population trends of grizzly bears in the Cabinet-Yaak and Selkirk ecosystems of British Columbia, Idaho, Montana, and Washington

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The authors summarize and report survival and cause-specific mortality of grizzly bears in the Cabinet–Yaak and Selkirk Mountains recovery zones from 1983–2002 to examine effects on the populations. Fifty-four percent of total known mortality in the Cabinet–Yaak was human-caused (n = 28), and 80% of total known mortality in the Selkirk Mountains was human-caused (n = 40). The authors Investigated demographic values of 53 and 61 radiocollared grizzly bears (Ursus arctos) and attendant offspring in the Cabinet–Yaak and Selkirk Mountains recovery zones, respectively from 1983–2002. Nineteen mortalities of radiocollared animals or offspring were detected in the Cabinet–Yaak sample and 20 in the Selkirk Mountains. Estimated survival rates were 0.929 (95% CI = 0.091) for adult females, 0.847 (95% CI = 0.153) for adult males, 0.771 (95% CI = 0.208) for subadult females, 0.750 (95% CI = 0.520) for subadult males, 0.875 (95% CI = 0.231) for yearlings, and 0.679 (95% CI = 0.179) for cubs in the Cabinet–Yaak. Estimated survival rates for the Selkirk Mountains were 0.936 (95% CI = 0.064) for adult females, 0.908 (95% CI = 0.102) for adult males, 0.900 (95% CI = 0.197) for subadult females, 0.765 (95% CI= 0.176) for subadult males, 0.784 (95% CI = 0.178) for yearlings, and 0.875 (95% CI = 0.125) for cubs. Reproductive rates were 0.291 and 0.284 female cubs/year/adult female for the Cabinet–Yaak and Selkirk Mountains recovery zones, respectfully. The annual exponential rate of increase (r) was –0.037 for the Cabinet–Yaak recovery zone and 0.018 for the Selkirk Mountains.

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ELECTRONIC FILE - Zoology: Mammals

SWAP (2/19/2016) citation:
Wakkinen WL, Kasworm WF. 2004. Demographics and population trends of grizzly bears in the Cabinet–Yaak and Selkirk ecosystems of British Columbia, Idaho, Montana, and Washington. [accessed 2015 Jun 01]; Ursus. 15(1):65–75. http://www.bearbiology.com/fileadmin/tpl/Downloads/URSUS/Vol_15_1/Wakkin...