Date of Award

5-1994

Degree Type

Dissertation

Degree Name

Doctor of Philosophy

Major

Ecology and Evolutionary Biology

Major Professor

Michael R. Pelton

Committee Members

Hamparsum Bozdogan, David Buehler, Jim Drake, Stephen C. Nodvin

Abstract

I used telemetry locations of American black bears (Ursus americanus), collected in Great Smoky Mountains National Park (GSMNP) from 1976 to 1982 , to evaluate home ranges, movements, and habitat use. Annual home range estimates averaged 7.6 km2 (SD = 7. 1) for females and 48.5 km2 (SD = 2 1 . 1) for males. For both sexes, fall ranges were larger than summer ranges and shifts occurred between summer and fall centers of activity. Annual and seasonal changes in spatial use of black bears are largely explained by changing activity and movement patterns in response to variation in distribution, abundance, and nutritive value of foods. Extensive home range overlap was common for both sexes and use of overlapping areas generally was unrelated to the presence of other bears of the same sex. There were some temporal intraspecific effects, however, because distances between locations of females and males collected simultaneously were greater than expected.

I analyzed habitat use of black bears based on 10 variables in a geographic information system (GIS) database using logistic regression of bear locations compared with random sites. I used Akaike's information criterion (AIC) and information-theoretic measure of complexity (ICOMP) to select the best predicting subset of habitat variables. Although the habitat use models fit the data, external validation of the overall model of female habitat use indicated that the model may be more appropriate for hindcasting than forecasting.

Female bear habitat use was best described by 4 micro- and 5 macro-scale variables whereas 6 macro-scale variables best explained male habitat use. Female use of habitat types was mostly restricted to areas of secondary importance for seasonal foraging. I hypothesize that female habitat use is partly a result of social interactions with males who may prevent females from using productive or otherwise important habitats. Future research should use an experimental approach to test this hypothesis of sex and reproductive class habitat segregation in black bears.

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