PARENT SESSION

Natural History 1 -- Session Chair: Patrick Zollner-- Nelson Hall East, Goodwin Forum

INFLUENCE OF SEX ON SEASONAL SPACE USE IN ABERT'S SQUIRRELS. Andrew J. Edelman and John L. Koprowski. School of Renewable Natural Resources, University of Arizona, Tucson, AZ.

ABSTRACT- Female and male mammals often differ in space use due to divergent reproductive strategies. We examined inter-sexual space use of polygamous Abert's squirrels (Sciurus aberti) during the mating and non-mating seasons. Female and male Abert's squirrels were radio-collared and home range characteristics and mating movements were determined using radio-telemetry. Based on the fixed-kernel method, home range size of females remained consistent between seasons, but tripled in males from non-mating to mating seasons. Home ranges overlap of both sexes by males, but not females, increased dramatically during the mating season. Males also moved 4 times farther than females to engage in mating activities. These results reflect the inter-sexual difference in strategies used to maximize reproductive success in tree squirrels. Female space use is relatively stable between seasons because reproductive success is dependent on food resources. Males increase home range size and overlap during the mating season to maximize contact with breeding females.

KEY WORDS: home range , Abert’s squirrels , fixed-kernel