Seasonal wolf predation in a multi-prey system in west-central Alberta
Estimating annual wolf kill rates and composition is important for assessing the impact of wolves on their prey and managing wolf-ungulate dynamics. Most studies have focused on kill rates of wolves in winter or single-ungulate dominated systems. I used high intensity GPS tracking combined with scat analysis to explored intra- and inter-seasonal variations in kill rates and prey composition of wolves in a multi-prey ungulate population. I found wolves in summer selected for neonate prey of all species with deer comprising the greatest proportion of both adult and neonate prey. Summer kill rates (0.21 ungulates/ adult wolf/day) were among the highest (~1.5-2.5 times) reported in the literature and were 2.5 times higher than winter rates (0.08+0.02), when wolves killed a greater diversity of predominately adult prey. Summer biomass consumption rates (4.22+0.36 kg/adult equivalent wolf/day) were lower than in winter (7.93+4.08), when wolves were less food limited. Seasonal differences in kill rates would have lead to significant underestimates (~29%) of annual kill rates when based on winter information only.