Food Habits of an Aoudad Sheep, Ammotragus lervia (Bovidae), in the Edwards Plateau of Texas

Abstract

Observations on selection of food items by a tame aoudad (Ammo- tragus lervia) while feeding in three habitat conditions were recorded. Forbs as a category ranked first in order of preference, grass second, and browse third although individual plant species would deviate from this generalization. Food consumption in the exclosure reflected forage preferences as influenced by habitat potential since this pasture represented an above average habitat condition. Forage consumption in the other two pastures reflected preference as influenced by availability controlled by animal use. Aoudad sheep have been successfully established on rangelands in New Mexico and Texas. New Mexico reportedly had 1,275 in 1959 (Ogren, 1965) located primarily in the Canadian River basin. Texas had approximately 1,300 in 1966 (Ramsey, 1969) located on at least 40 ranches over the state. In Texas, the Palo Duro Canyon in the pan- handle and the Edwards Plateau in the central region contain the largest numbers. Since these animals were introduced in important domestic livestock and native big game areas, knowledge of food habits was needed to determine the degree of competition between the aoudad and other large herbivores. Ogren (1962) analyzed 95 rumen-content samples from aoudads inhabiting cliffs and side-canyons of the Canadian River gorge in New Mexico. The combined yearly average of all samples collected in all seasons was 50% browse, 40% grass, and 10% forbs by volume. Of the 79 different plants identified, two species, mountainmahogany (Cercocarpus breviflorus) and wavy leaf oak (Quercus undulata), accounted for half the food volume.