Denning Ecology of Black Bears in a Southeastern Wetland

Abstract

We investigated den characteristics and denning chronology of black bears (Ursus americanus) in the Great Dismal Swamp (GDS), a forested wetland in Virginia and North Carolina. We monitored 35 bears (26 F, 9 M) throughout the winters of 1984-85, 1985-86, and 1986-87. Den types included 14 ground nests, 11 excavated ground cavities, 2 ground-level tree cavities, 1 above-ground-level tree cavity, and 1 stump den. Three dens were in areas of inundation. Pregnant females entered dens earlier (P < 0.02), emerged later (P < 0.001), and denned longer (119 ? 4 [SE] vs. 78 ? 4 days) than other age and sex groups. Denning periods were among the shortest reported for black bears. Although den site availability was not estimated, dry den sites did not seem to be limited. Large den trees may not be necessary for successful denning and reproduction in certain southeastern wetlands because bears can use dense cover and microelevational factors