With the reintroduction of gray wolves (Canis lupus) to Yellowstone National Park (YNP), much interest has been shown regarding the effects of a restored wolf population on both grizzly bears (Ursus arctos horribilis) and black bears (Ursus americanus). Grizzly bears, black bears, and gray wolves have historically coexisted in much of the same range throughout a large portion of North America (Brown 1993).