Prey Taken by Colonizing Wolves and Hunters in the Glacier National Park Area

The recent colonization of the northwestern United States by an endangered wolf (Canis lupus) population has raised concerns among hunters regarding competition for prey. Data on wolf prey selection may dispel misperceptions and thereby decrease human-caused wolf mortalities that would affect wolf recovery. We assessed the extent to which the early stage of colonization affected wolf prey selection by comparing our results with those from established wolf populations. We examined 243 prey killed by colonizing wolves in the Glacier National Park area of Montana and adjacent British Columbia during winters 1985-91 and compared characteristics of these with those of ungulates killed by hunters. Wolves killed a larger proportion of white-tailed deer (Odocoileus virginianus) fawns (P < 0.05) and elk (Cervus elaphus) calves (P < 0.05) than did hunters; they also killed older (P < 0.05) white-tailed deer and were more likely to kill older elk than were hunters. Male white-tailed deer (P < 0.001) and elk (P < 0.001) were killed by wolves at a disproportionately high rate relative to their occurrence. Colonizing wolves killed a higher proportion of white-tailed deer fawns and elk calves than did wolves in established populations elsewhere. Deer (P < 0.001) and elk (P < 0.05) carcasses were more completely consumed during winters with shallow snow than during deep-snow winters. Overall, the degree to which a carcass was consumed was high and apparently a function of pack size. The most vulnerable ungulates, the old and juveniles, were more likely to be killed by wolves than by humans, reflecting different selection patterns.