WHITE-TAILED DEER AND CATTLE DIETS AT LAMICHILIA, DURANGO, MEXICO

Fecal analysis was used to determine the relationships between white-t ailed deer (Odocoileus virginianus couesi[Coues and Yarrow]) and cattl e diets (Beef Master, Hereford and criollo), in Durango, Mexico. Deer preferred shrub and tree species (85% of the diet), whereas cattle pre ferred grasses (61%). Although diets varied seasonally, as did forage availability and quality, the same selective forage pattern was mainta ined throughout the year. There was a significant difference in the us e of different plant groups between the 2 herbivores. The diet overlap index (50.51%) suggested competition during the wet season, but forag e was abundant (628 kg/ha dry weight biomass compared with 380 kp!ha i n the dry season), thus reducing potential conflicts. Deer and cattle can simultaneously forage in this area without detriment to either spe cies. The vegetation can maintain a stable composition under higher ut ilization levels when used by 2 herbivores with different forage patte rns than when used by only 1 herbivore.