EFFECTS OF HABITAT ENRICHMENT ON PATTERNS OF DIET SELECTION

Foraging theory predicts that animals should feed more selectively in response to an increased abundance of high-quality foods. We tested th ese predictions by examining changes in patterns of diet selection by white-tailed deer (Odocoileus virginianus) and Angora goats (Capri hir cus) in response to habitat enrichment. When a high-quality supplement was provided ad libitum, both species responded by increasing foragin g effort and by feeding more selectively on natural forages. Supplemen ted animals consumed a greater proportion of plants containing high co ncentrations of crude protein (CP) and digestible energy (DE), which r esulted in an increase in average diet quality. Responses of individua l deer and goats varied and appeared to be related to differences in h abitat heterogeneity between trial enclosures. Our results suggest tha t supplementation may be disruptive to normal behavioral processes aff ecting the distribution of free-ranging herbivores on the landscape. T hese processes may be important in reducing the probability of excessi ve utilization of palatable forage species, and to the competitive rel ationships between range plants.