Ecology of Florida Black Bears in the Okefenokee-Osceola Ecosystem

The population status of the Florida black bear (Ursus americanus floridanus) is problematic within many portions of its range and its potential listing as a federally threatened species has been the subject of legal debate. We studied Florida black bears in 2 areas in the Okefenokee-Osceola ecosystem in southeast Georgia (i.e., Okefenokee) and north Florida (i.e., Osceola) from 1995 to 1999 to evaluate relationships between population characteristics, habitat conditions, and human activities. Bears in Okefenokee were hunted and those in Osceola were not. We captured 205 different black bears (124M:81F) 345 times from June 1995 to September 1998. We obtained 13,573 radiolocations from 87 (16M:71F) individual bears during the study. In Okefenokee, black gum (Nyssa sylvatica) and saw palmetto (Serenoa repens) fruits were the most important foods for bears based on scat analysis. In Osceola, corn from white-tailed deer (Odocoileus virginianus) feeders was the most stable food source but saw palmetto was heavily used when available. Corn from deer feeders was not available in Okefenokee. Adult bears in Osceola were 29% heavier than those in Okefenokee ($t_{82}=3.55$, P < 0.001). The mean annual home-range size for Osceola females ($\overline{x}=30.3\ {\rm km}^{2}\pm 4.0\ [{\rm SE}]$, n = 53) varied little seasonally or annually and was almost half that of Okefenokee females ($55.9\ {\rm km}^{2}\pm 6.9$, n = 69; Z = -2.47, P = 0.014). In contrast, radiocollared females in Okefenokee expanded their home ranges during years of poor black gum production. That expansion was most apparent between autumn 1998 and 1999, when mean home-range size for Okefenokee females increased from $14.5\ {\rm km}^{2}$ to $78.4\ {\rm km}^{2}$, respectively, and included a larger proportion of upland areas open to sport hunting. As a result, 5 females were harvested in the Okefenokee study area during the 1999 bear hunting season compared with only 7 harvested from 1996 to 1998. Home ranges of adult female bears were located in areas with disproportionately high loblolly bay (Gordonia lasianthus) and gum-bay-cypress (Taxodium spp.) vegetation associations in Okefenokee and gum-bay-cypress associations in Osceola. The pine vegetation association ranked lower than most other associations within the home ranges of bears in both study areas even though much of the summer and autumn diets of bears included food items found almost exclusively in pine. Sixteen mortalities of radiocollared be