Interactions between coyotes and red foxes in Yellowstone National Park, Wyoming

Abstract

Interactions between coyotes (Canis latrans) and red foxes (Vulpes vulpes) indicate that coyotes often tolerate foxes, and yet at other times, are aggressive and kill foxes. The frequency and context in which coyotes are aggressive or tolerant of foxes are unknown. We observed 66 interactions between coyotes and red foxes in Yellowstone National Park, Wyoming, from February 1991 to April 1993. Foxes were deterred, displaced, or tolerated by coyotes in 17, 30, and 53% of the encounters, respectively. Deterrence and displacement of foxes by coyotes occurred at a similar frequency in the absence and presence of an ungulate carcass. Tolerance of foxes by coyotes occurred most frequently in the absence of a carcass. A group of coyotes feeding or resting at a carcass was a deterrent to approaching foxes.