Coyote (Canis latrans) diet in the Blue Range Recovery Area, Arizona and New Mexico

Control and extermination of wolves (Canis lupus) in North America has been associated with a coyote (Canis latrans) range expansion. With the natural recolonization and wolf reintroduction programs during the last few decades in some areas, wolves have eliminated coyotes. In other areas, coyotes maintain high densities in the presence of moderate wolf densities. Interactions between wolves and coyotes can have significant impacts on their distribution and abundance. The purpose of this study was to describe the coyote diet and compare it to the diet of the recently reintroduced Mexican wolf in Arizona and New Mexico. Scats were collected from April 1998 through October 2001, in an opportunistic sampling strategy. Scats were broken apart by hand and undigested parts of food items were separated and identified with the aid of a reference collection. We found that coyote diet was composed mostly of mammalian species followed by vegetation and insects. Elk was the most common food item found in coyote scats. Mexican wolf diet had a higher proportion of large mammals and less small mammals than coyote diet did; however, elk was also the most common food item found in Mexican wolf scats. Our results suggest that Mexican wolf diet although different from coyote diet, had less large mammals and more small mammals and was more similar to coyote's diet than previously reported. Considering results in other areas, we could expect that Mexican wolves will have a negative impact on coyotes.