Resource distribution, female home range dispersion and male spatial interactions: group structure in a solitary carnivore

Abstract

We monitored 74 (41 male, 33 female) radiocollared raccoons (Procyon lotor) from February 1990 to July 1992 on the Welder Wildlife Refuge, Texas, to relate male and female space use to each other and to the spatial distribution of water, a critical resource for raccoons. Female home ranges were spatially aggregated early in the study, when standing water occurred in only a few, widely separated patches on the study site, but were randomly distributed during seasons when water was more widely distributed. Adult females generally foraged and rested independently of other adults. Most adult males were arranged in spatial groups whose home ranges overlapped little with those of adjacent groups. These groups were usually composed of three to four individuals; Doncaster's (1990,J. theor. Biol.,143, 431–443) test for dynamic interaction and visual observations showed that group members tended to associate positively during resting and foraging activities in all seasons. Among raccoons, as among many other mammals, female spatial patterns are apparently determined primarily by resource distribution, whereas male patterns are influenced by the distribution of females.