Property damage associated with black bears searching for and procuring foods intended for visitor consumption within developed campground areas has been a continuing management problem within Sequoia National Park. A computer model was developed to examine the relationship between seasonal changes in the quantity and quality of bear foods and the magnitude of the bear-visitor problems by simulating seasonal changes in bear distributions within major habitat types. Five habitat types were differentiated on the basis of the relative abundance of seasonally important black bear foods: manzanita berries, acorns, yellow jackets, wet meadow grasses and forbs, and visitors' food. Location of a bear in a particular habitat type was theorized to be a function of both relative abundance of all available foods and the food qualities as measured by digestible energy. Bears were assumed to maximize their net energy input by minimizing energy expended while searching and maximizing the quality of the foods ingested. Values reported in the literature were used to estimate digestibility. Seasonal abundance of the different foods was estimated from 1974 and 1975 field data. Actual bear density data showed trends similar to the simulated bear distributions. Simulated bear management strategies employing relocation or permanent removal were generally ineffective as long as only poor quality natural foods were available. Reduction in campground food availability significantly reduced simulated bear numbers in the campground areas.
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