Livestock depredation by wolves and the ranching economy in the Northwestern U.S

Due primarily to wolf predation on livestock (depredation), some groups oppose wolf (Canis lupus) conservation in the Northwestern U.S., which is an objective for large sectors of the public. Livestock depredation by wolves is a cost of wolf conservation borne by livestock producers, which creates conflict between producers, wolves and organizations involved in wolf conservation and management. Compensation is the main tool used to mitigate the costs of depredation, but this tool may be limited at improving tolerance for wolves. Furthermore, livestock production may in fact provide indirectly an important benefit for wolf conservation - i.e. a positive externality, by maintaining relatively intact habitat on private lands. We analyzed some of the costs of livestock depredation by wolves to livestock producers relative to recent economic trends in the livestock production industry, specifically income generated from livestock production and trends in land and livestock value. Data were gathered from depredation investigations, from the livestock compensation program and on land and livestock price in Idaho, Montana and Wyoming, U.S.A. from 1987 to 2003 - a period during which wolves had endangered species status. We found that instigation of attacks on livestock by wolves was determined by need for food, but wolves may kill sheep in excess of food needs. Excessive killing of livestock may contribute significantly to intolerance for wolves. Livestock killed by wolves cost producers approximately $11,076.49 per year between 1987 and 2003, although costs were increasing linearly (R2Â =Â 0.789, PÂ