1) Are coyotes deer specialists, thereby filling the vacant niche of the wolf rather than co-opting the niche of extant carnivores?

2) How much do coyote diets overlap native carnivores, and by what means might they establish a stable coexistence?

We constructed a timeline of coyote diet from the 1950s to today, and related coyote use of prey to changes in prey abundance. We documented dietary overlap among coyote, bobcat, gray fox and red fox using stable isotope analysis. Despite high use of deer, coyotes are not deer specialists. Rather, deer use depends on the abundance of primary prey, specifically snowshoe hare (historically) and beaver (currently). As coyotes increasingly exploit beaver populations, we expect use of adult deer to continue to decline. However, use of fawns remained constant despite primary prey availability, so if coyote numbers increase as a result of abundant beaver then total predation on fawns may increase too.

Native carnivores appear sufficiently flexible to achieve a stable coexistence with coyotes. Coyote, gray fox and red fox diets largely overlap, but fox coexist with coyotes by exploiting predation refuges – gray fox by climbing trees and red fox by occupying human-dominated areas. However, red fox use of human development may become problematic if it leads to increased human-wildlife conflict.