Black Bear, Ursus americanus, Denning Chronology and Den Site Selection in the Northeastern Cascades of Washington


  • William L. Gaines U.S. Forest Service, 215 Melody Lane, Wenatchee, Washington 98801



Black Bear, Ursus americanus, northeastern Cascade Mountains, denning chronology, den site characteristics


I studied Black Bear denning chronology and den site selection during 1995-1998 in the northeastern Cascade Mountains of Washington. Male Black Bears entered dens between 22 October and 19 November and emerged between 4 April and 7 May. Females entered dens somewhat sooner, between 15 October and 19 November, and emerged later than males, 4 April and 22 May. These den entry and emergence dates were similar to those reported at similar lattitudes in northwestern Montana. Roads had an important influence on den site selection by Black Bears in this study area. Bears selected dens in areas with no open roads >200 ha in size, >500 m from the nearest open road, and 1500-2000 m in elevation. The combination of information on denning chronology and site characterstics should allow managers to coordinate human activities to reduce the potential for disturbance to denning Black Bears.