Population Ecology of Black Bears on Camp Lejeune, North Carolina
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Fifteen black bears (Ursus americanus) were captured 24 times on Marine Corps Base Camp Lejeune, North Carolina, during 1988 and 1989. Females dominated the capture sample, but age did not differ between the sexes (P=0.31). No subadult males were captured during the study. Mean litter size was 2.2 (n=6) with females attaining primiparity at age 4. Breeding may occur at age 3; den observations-and teat development suggested previous parturition in a four-year old. Estimated annual survival rates were 0.77 for males, 0.69 for females, and 0. 53 for cubs. Causes of mortality included vehicle collisions (n=S), research (n=l), and legal kill (n=l; outside the study area). Population density for the study area was estimated by 4 techniques at 0.16-0.30 bears/km2 , or 21-40 bears. Twenty three bears were known to inhabit the base as residents or seasonal migrants. Denning ecology was described for 14 bears (12F, 2M). Winter activity was recorded for 5 of 7 bears in 1989 and 3 of 7 bears in 1990. Two bears (1 adult male, 1 subadult female) used multiple den locations. Bears denned exclusively on ground nests in three habitat types; pocosin (n=ll), lowland pine-hardwood (n=2), and an area of forest regeneration (n=l). Vegetation density at the hibernacula (x=94%) was greater (P<0.001) than random locations. Prescribed burns resulted in 4 den abandonments (50% of all