From venison to beef: seasonal changes in wolf diet composition in a livestock grazing landscape

Wild ungulates are the primary prey for wolves in North America, but livestock predation is a concern in areas where wolves and livestock overlap. Using clusters of global positioning system telemetry relocations and scat analysis, we investigated wolf diets year-round in southwestern Alberta, where seasonal cattle grazing is the predominant land use and wolf cattle conflicts have increased in recent years. Both methods indicated a seasonal shift in wolf diets, from wild prey during the non-grazing season to cattle in the grazing season. Wolves scavenged more frequently during the non-grazing season than during the grazing season; 85% of all scavenging events occurred at ranchers' boneyards (where livestock carcasses are dumped), where wolves fed on dead livestock. Cattle represent a higher proportion of wolf diets than previously thought; we recommend the sanitary disposal of dead livestock to prevent wolves from becoming accustomed to feeding on livestock, and the development of management plans aimed at reducing predation on cattle if humans and wolves are to coexist on landscapes that are dominated by livestock ranching.