Comparative Diet Analysis of Canis rufus and Canis latrans

Abstract

Top predators control the biodiversity of plant life through regulation of both meso-predator and herbivore populations, a phenomena referred to as top-down effects. In areas of the Southeast where red wolves (Canis rufus) were once the top predators, meso-predator populations have flourished while the biodiversity of these ecosystems have declined. The recent appearance of the coyote (Canis latrans) in the former range of red wolves through their migrations eastward implies a potential for coyotes to fill the ecological niche left by red wolves. The similarity in size between coyotes and red wolves might indicate that coyotes could assume the former role of the red wolves due to their ability to hunt larger prey and consequently cause top-down effects in former red wolf ecosystems. To assess the possible ecological niche similarities of the two canid species, a comparative diet study is being conducted by analyzing more than 400 samples of coyote scat collected from the Yawkey Wildlife Center in Georgetown, SC from 2009-2011. Teeth and hair recovered from the scat samples will be identified to the lowest possible taxonomic level using mammal hair identification keys, as well as reference hairs and teeth. The results of the diet analysis will be compared to the documented diet of red wolves. If no significant diet overlap is observed then it could be assumed that coyotes have not assumed the functional role of the red wolf. A significant overlap in coyote and red wolf diets might indicate that the coyote is filling the role of top predator. These results have implications for management of ecosystems where red wolves were once abundant and now coyotes are prominent. If coyotes function as top predators, wildlife management plans should incorporate the potential top-down effects caused by coyotes when deciding on policies concerning biodiversity of flora and fauna in the local ecosystems.