INFLUENCE OF NATURAL FOOD ABUNDANCE ON BLACK BEAR HARVESTS IN MINNESOTA

Many agencies use data on hunter success and harvest composition to gu ide decisions about black bear (Ursus americanus) management, despite well-known limitations of such data. The likely influence of natural f ood abundance on harvests has been acknowledged, yet few studies have examined this relation. We conducted a simple survey, employing subjec tive ratings by experienced observers, to monitor food abundance acros s Minnesota's bear range, and used these data to interpret a le-year r ecord of hunting success and harvest composition. Percent females in t he harvest, mean age of females killed, and hunting success were relat ed inversely to fall food abundance, particularly hazelnuts (Corylus s pp.) and acorns (Quercus spp.). Percent females in the harvest, mean a ge of females killed, and estimated harvest rates for most sex-age cla sses, particularly adult females, also increased with increased number of hunters. After accounting for fall food and number of hunters, the estimated size of the bear population appeared to have little effect on hunting success and harvest sex ratio; that is, bear harvest data a pparently yielded little insight into population status. Despite the s imple format and subjective nature of our food survey, it adequately e xplained most of the year-to-year variation in hunting success and the sex-age composition of the harvest.