Habitat Utilization and Movement Ecology of Black Bears in Cherokee National Forest

Home range, movements, and habitat use of black bears in the Cherokee National Forest were monitored from June 1980 through December 1981.

In 1980, home range sizes averaged 192 km² for male bears and 23 km² for females, whereas the average range in 1981 for males was 60 km² and 15 km² for females. Larger ranges for males likely reflect a social structure that enhances reproduction. Differences in home range sizes between years was attributed to the availability and abundance of hard mast, especially acorns. Both sexes exhibited seasonal shifts in range use between summer and fall. Males traveled greater distances between summer and fall ranges than female bears.

Diel movements were affected by time of year, different foraging strategies between seasons, and mating activities. Both sexes moved greater distances in diurnal periods than nocturnal periods. Nocturnal movements were extensive only during fall. Increased nocturnal movements in fall were associated with seasonal changes in food sources, preparation for denning, and the influence of human-related activities.

Bears exhibited crepuscular patterns of activity that were modified seasonally. Activities of bears were affected by weather factors, distribution and availability of foods, seasonal changes in foraging strategies, and denning. Sex, age, and reproductive classes also affected activity patterns. Adult male bears were the most active group, whereas females with cubs were the least active. The pattern of activity for bears in the CNF suggests that breeding may occur in early August.

Factors affecting habitat use included season, individual behavioral differences among bears, reproductive classes, and variations in hard mast production between years. Occurrence of bears in hardwoods increased significantly during 1980 when acorns and hickory nuts were scarce.

Habitat preference was also determined by a utilization-availability analysis. Hardwoods were preferred, although some variations in habitat use were sex related. Male bears used hardwoods (chiefly oaks) more than expected in terms of their availability, whereas females occurred more than expected in softwoods (chiefly pines).