Study analyzes 25 years of data
The gray wolf was federally listed as endangered in 1974. During much of its recovery in the northern Rocky Mountains, government predator control efforts have been used to keep wolves from attacking sheep and livestock. With wolves delisted in 2012, sport hunting has also been used. But until now, the effectiveness of lethal control has been what Wielgus and Peebles call a “widely accepted, but untested, hypothesis.”
Washington State University wildlife biologist Rob Wielgus is studying lethal and non-lethal methods to keep wolves from preying on livestock. (Photo by Kay Morris)
Their study is the largest of its kind, analyzing 25 years of lethal control data from U.S. Fish and Wildlife Services Interagency Annual Wolf Reports in Montana, Wyoming and Idaho. The researchers found that killing one wolf increases the odds of depredations 4 percent for sheep and 5 to 6 percent for cattle. If 20 wolves are killed, livestock deaths double.
Work reported in PLOS ONE last year by Peebles, Wielgus and other WSU colleagues found that lethal controls of cougars also backfire, disrupting their populations so much that younger, less disciplined cougars attack more livestock.
Still, Wielgus did not expect to see the same result with wolves.
via Research finds lethal wolf control backfires on livestock – WSU News Washington State University.