Temporal variation in foraging patterns of Desert Kit Foxes (Vulpes macrotis arsipus) in the Mojave Desert, California, USA

摘要

Ecological studies on the Desert Kit Fox (Vulpes macrotis arsipus) in California, USA are severely lacking. Although the Desert Kit Fox does not have any formal protections in California, conservation concern for this subspecies is increasing markedly. We conducted a five-year multi-season dietary study in the Mojave Desert near the city of Barstow, California, USA, in which we collected and analyzed over 1,200 Desert Kit Fox scats. Desert Kit Foxes specialized on heteromyid rodents, even when this preferred prey declined during a drought. Invertebrates were also regularly consumed and use of this prey type increased when rodents decreased. Opportunistic items such as birds, reptiles, and Pistachio (Pistacia vera) nuts supplemented the Desert Kit Fox diet. We conclude that Desert Kit Foxes in California are rodent and invertebrate specialists, but they have sufficient ecological plasticity to expand their diet in response to environmental changes, similar to other canids. Management strategies should thus include steps to maintain healthy prey populations as well as a variety of available food options in the event of declines in primary foods. Ecological plasticity may allow Desert Kit Foxes to adapt and persist despite anthropogenic landscape modifications and potential climate change.