Food Habits and Dietary Overlap of Elk and Mule Deer in Guadalupe Mountains National Park, Texas

Abstract

Botanical composition of elk (Cervis elaphus nelsoni) and mule deer (Odeocoileus heminous crooki) diets were determined using microhistological examination of fecal material from March, 1978 through February 1979 in Guadalupe National Park, Texas. Annual diets of elk consisted of 48% browse, 32% grasses, and 20% forbs. Oaks (Quercus spp.), desert ceanothus (Caenothus greggii), curlyleaf muhly (Muhlenbergia setifolia), blue grama (Bouteloua gracilis), and common horehound (Marrubium vulgare) were the major forages used by elk. Annual mule deer diets consisted of 77% browse, 21% forbs, and 2% grasses. Oaks, desert ceanothus, mountain mahogany (Cercocarpus montanus), bladderpods (Lesquerella spp.) were the primary forages consumed by mule deer. Overall, annual dietary overlap was moderately high (58%). Overlap was greatest in the browse component and was highest during spring (91%) and summer (65%).