The repatriation of wolves to Isle Royale alters the foraging of meso-carnivores.

This article examines the effects of gray wolf (Canis lupus) reintroduction on the foraging ecology of two meso-carnivores, Red Fox (Vulpes vulpes) and American Marten (Martes americana), within the simplified vertebrate community of Isle Royale National Park. Using scat analysis and stable isotope data collected before and after wolf repatriation, the study found that wolf reintroduction had little impact on marten diets but influenced fox diets at the individual level, with some foxes increasing consumption of large carrion (notably moose) and human food, thereby increasing dietary overlap with martens. At the population level, both species remained dietary generalists consuming small prey, berries, and human food regardless of wolf presence. The findings highlight how the return of a large carnivore can alter trophic interactions by provisioning carrion and shifting foraging strategies among subordinate carnivores in a relatively simple ecosystem.