Wolf Predation on Elk in Riding Mountain National Park, Manitoba

Abstract

Winter food habits of C. lupus were studied in Riding Mountain National Park in 1978-1979 by tracking radio-marked animals and checking kills on the ground. C. elaphus, moose (Alces alces), and white-tailed deer (Odocoileus virginianus) were the major prey species. Ungulate densities for the park were 1.4 elk, 0.94 moose and 0.34 deer/km2. Elk outnumbered moose by 2.4:1 in the study area, but as prey elk outranked moose by 15:1. Elk formed the main food base for the wolf population. In a mild winter with low snowfall, a pack of 3 wolves killed elk and deer but not moose. A pack of 5 wolves showed a strong preference for elk during a year with deep snow. The mid to late winter kill rate, under unusually deep snow conditions, was 1 elk or moose every 2.7 days. The calculated daily food consumption was 0.21 kg of prey/kg of wolf. Killing of prey in excess of needs occurred in late winter as carcass use was incomplete. Kill rate per wolf was 1 elk/14 days. Kill abandonment was not related to prey size, with the time spent at kills varying from 1.4-1.5 days for adults and calves, respectively. Mean straight-line distance between kills was 5.1 km. There was no clear pattern of elk distribution within wolf territories and kills were in a random pattern within territories. Wolves killed a larger proportion of young and old elk when compared to hunter kills adjacent to the park. Length of discernible classes varied from 20-260 m. Predation on elk calves was greater in early to midwinter; predation on cows increased in late winter. Condition of prey, based on femur fat, was good to excellent.