Effect of Yosemite Backcountry Use Levels on Incidents with Black Bears

Photo by Jeff Keay

Keay, J. A. and J. W. Van Wagtendonk. 1983. Effect of Yosemite backcountry use levels on incidents with black bears. Ursus 5:307-311.

ABSTRACT: Black bear (Ursus americanus) incidents, defined as property damage or personal injury by bears, increased dramatically in recent years in the back country of Yosemite National Park, California. Since all backcountry zones do not receive the same level of visitor use, incidents could be compared between zones of various use levels. Data collected from 1976 through 1979 showed that as visitor density increased, reported bear incidents increased linearly. In order to reduce or maintain bear incidents at acceptable levels, managers of backcountry areas may have to reduce nonaversive bear/human encounters and the availability of human food items.