SELECTION OF CRICETINE PREY BY THE CULPEO FOX IN PATAGONIA - A DIFFERENTIAL PREY VULNERABILITY HYPOTHESIS

The Patagonian culpeo fox (Dusicyon culpaeus) feeds in part on the cri cetine rodent community. A previous diet study based on seats revealed that these foxes show a marked preference for 3 Akodon species (Akodo n longipilis, Akodon xanthorrinus and Akodon iniscatus), in contrast w ith the notably more abundant sympatric mouse, Eligmodontia typus. For invertebrates and fish, prey selection of this sort has been often an alyzed comparing differential prey vulnerability. However, this event has never been explicity studied in mammalian communities. In this pap er, we have attempted to analyze the Patagonian fox's prey preferences through a field based prey vulnerability study. To do so, we compared behavioural and morphological attributes that could account for diffe rences in the predators success (studied separately through stomach co ntent analysis). Our results show that there are differences in the vu lnerability of these prey species which are based mainly upon a greate r escape ability of E. typus related to their longer hind legs. We con clude that analyses such as these, which are simple and economical, ca n provide interesting data on which future experimental work on carniv ore prey choice may be based upon.