Conservation biology and management of wolves and wolf-human conflicts in western North America

Management of wolves (Canis lupus) can be controversial, reflecting a multitude of public attitudes. In Alberta, Canada (1982 to 2001) and in Idaho, Montana and Wyoming, USA (1987 to 2001), wolves killed various domestic animals among which sheep were the major prey in the USA (68%, n=494) and cattle in Canada (95%, n=1633). Under recovery programs, wolves increased in the USA and livestock predation events increased proportionately. In both countries, the number of domestic animals killed each year was correlated with the number of wolves killed for livestock predation management. I tested anti-wolf barriers made of flags hanging from ropes. Barriers prevented captive wolves (n=9) from accessing food for up to 28hr. Barriers were also set around two 100-m2 baited sites and two 25-ha cattle pastures. During 60-day trials, wild wolves approached, but did not cross, barriers on 57 occasions. Wolves killed cattle on neighbouring ranches during the trials, and before and after the trials in the tested ranches. Barriers deployed around a400-ha pasture were crossed by wolves after 61 days. Barriers could play a role among the limited set of preventative measures available for livestock predation management on a local scale. The alternative is culling, which is particularly contentious in areas, such as the conterminous USA, where wolves are threatened. If conservation is a priority, then culling and hunting should be evaluated depending on the characteristics and size of wolf Evolutionarily Significant Units (ESUs). I tested whether wolf-prey associations in tundra, taiga and forested regions of Canada explained differences in genetics, morphology and behaviour of wolf ESUs. Satellite collar data demonstrated that tundra wolves (n=19) migrated with barren ground caribou (n=19). I also analysed 404 wolf tissue samples. Although tundra/taiga wolves overlapped with forest conspecifics during the winter breeding season, they were differentiated from them (Fst=O.30, 0.04 and 0.07, p<0.001, for mitochondrial, microsatellite and Y-chromosome markers, respectively). Further, 93% of tundra/taiga wolves exhibited pale colouration whereas only 38% of forest wolves did (Z=85.53, p<0.0001). Tundra/taiga migratory and forest territorial wolves therefore constitute distinct ESUs for which impacts should be assessed. My results revealed that prey specialization should always be accounted for when planning wolf conservation.