Habitat selection by two desert-adapted ungulates

Habitat selection, as a reflection of an animal's need to satisfy its life requirements was studied in two indigenous ungulates, the Asiatic wild ass (Equus hemionus) and dorcas gazelle (Gazella dorcas), under conditions of extreme aridity in the Negev desert. These ungulates had significantly different spatial distributions. The relative abundance of wild asses was positively correlated with plant species richness and the percentage cover of known forage species, and negatively correlated with the incidence of earlier browsing. There was no significant relationship between plant species distribution and habitat selection by the dorcas gazelle. It is possible, however, that the scale at which foraging opportunity was evaluated, namely the plant species level, masked habitat selection by the gazelle. Interestingly, the occurrence of dorcas gazelles was positively associated with access to perennial surface water. This is an unexpected result in a species known to be independent of free water for drinking. This result indicates, that while the gazelle can survive without free water should the need arise, it preferentially utilises habitats with access to drinking water.