Home Range and Habitat Use by Black Bears in Southwestern Washington

Movement and activity of 16 black bears (Ursus americanus) of a population of 23 were monitored by radio telemetry between March 1973 and October 1975 on an island in southwestern Washington. Average home-range sizes of adult males (505 ha) and females (235 ha) were markedly smaller than home-range estimated for bears in other parts of the United States. Richness of habitat on the island presumably allowed smaller home ranges. Home ranges of sex and age groups overlapped, with use of shared areas apparently determined by a social hierarchy. Males varied more than females in seasonal use of their home ranges. Bears used certain vegetation types on the island disproportionately to their availability, apparently selecting for areas logged since 1963 and against areas logged before 1935. J. WILDL. MANAGE. 41(3):413-425 Historically, management of the black bear has relied principally on the gun. Before studies by Stickley (1957), Black (1958), Erickson et al. (1964), and Jonkel and Cowan (1971), biological data for this species that could be used in management planning were essentially nonexistent. Data from these studies, however, are often limited in their application because of regional differences. In the Pacific Northwest where clearcutting, the dominant timber harvesting technique, dramatically alters the vegetative composition of thousands of hectares each year, and demands of both sportsmen and timber industry influence black bear management policies, the need for biological data concerning the black bear is obvious. Before a study by Poelker and Hartwell (1973), to which the late D. Pierson made significant contributions, game agencies in Oregon and Washington used biological information from other regions. Emphasis of that study, however, was directed at investigating the reasons black bears damaged