Evaluation of Wolf Control to Reduce Cattle Predation in Alberta

Abstract

Results of wolf (Canis @I.@ control to reduce predation of cattle in northwestern Alberta are reported. Numbers of wolves declined from about 40 prior to control to 3 following the strychnine poisoning of 26 wolves during 2 winters, 197PsO and 1980-81. Additional losses of wolf pack members occurred from natural mortality and dispersal following the removal of the majority of their packmates. In 3 of 6 instances where packs took baits, entire packs of 2,4, and 6 wolves were killed. Ingress of wolves occurred within 1-2 years. Total mortality of cattle declined from a mean of 64 (3.4%) during 4 years prior to control to 36 (Xg$@during 2 years following control. Selectivity of strychnine poisoning was rensonably good although more emphasis on preventive management is recommended. Wolf (Cam3 lupus) depredations of livestock and subsequent wolf removal have occurred throughout the settlement of North America (Young 1944, Lopez 1978) and currently occur in western Canada (Gunson 1983a), Ontario (Kolenosky 1983), and Minnesota (Fritts 1982). Despite controversy and costs associated with these control programs, evaluations have been limited. In Alberta, wolves occur in the northern and western two-thirds of the province, with current numbers estimated at about 4-5,000 (Gunson 1983b). Wolf-livestock complaints are most common near the forest-agricultural fringe in Alberta and other isolated areas of the province. The Alberta Fish and Wildlife Division (AFW) initiated annual livestock-related wolf control in 1972, consisting of complaint investigation and removal of wolves if predation or mauling was confirmed. During 9 years (1972-8 l), 729 wolves were known to have been removed. Results of wolf control conducted during studies of wolf predation of cattle in northwestern Alberta during 1975-81 are evaluated. This paper reports details of wolf removal, nontarget kill, response of wolves to vacant territories, and the impact of wolf removal on cattle. Results are discussed in relation to management of wolf-livestock conflicts.