Causes and consequences of sexual habitat segregation in grizzly bears ...

• Main Author: Wielgus, Robert B.
• Format: Text
• Language: English
• Published: University of British Columbia 2008
• Subjects: Ursus arctos
• Online Access: https://dx.doi.org/10.14288/1.0075204; https://doi.library.ubc.ca/10.14288/1.0075204

I studied habitat use and population dynamics of 2 grizzly bear (Ursus arctos) populations to test 3 competing hypotheses of sexual habitat segregation (no avoidance, food competition, and sex competition) and 3competing hypotheses on the effects of adult male mortality on female reproduction (additive, compensatory, depensatory). Twenty bears were radio-monitored from 1980 to 1984 in Kananaskis, Alberta and 28 bears were radio-monitored from 1985 to 1990 in the Selkirk Mountains of Idaho and British Columbia. The Kananaskis population had high mortality of older adult males and a corresponding influx of younger immigrant males. That population had a low reproductive rate and appeared to be declining. The Selkirk population had low mortality of older adult males and few younger immigrant males - that population had a high reproductive rate and appeared to be stable. Sexually mature adult females avoided food-rich, male-occupied habitat in Kananaskis where there were many potentially infanticidal, immigrant ...