WHITE-TAILED DEER, ODOCOILEUS-VIRGINIANUS, SUMMER DISPERSION AREAS INONTARIO

Between 1983 and 1989, 168 White-tailed Deer (Odocoileus virginianus) were radio-tracked as they migrated out of nine deer yards in Ontario. For four of these yards we tested the hypothesis that summer dispersi on areas should be 10 X larger than their associated deer yards since winter range deer densities are about 10 X summer range densities. We found that summer dispersion areas were 13 X larger than their winter yards in terms of forested area, and that the expansion factor wa not different form the hypothesized value (P > 0.830). Our results suggest ed that a reasonable approximation of the size of a summer dispersion area could be achieved by multiplying yard area by 10, and correcting the results to account for forest cover. The ability to predict the si ze of a summer dispersion area from yard is important for evaluating t he effects of changes to winter and summer range habitat, over or unde r harvest of deer, and changes in natural deer mortality rates. The re lative ease of defining winter yard boundaries simplifies the use of t his spatial relationship in management.