After bison herds disappeared from the Great Plains in the 1880s, wolves turned to livestock for prey. Western states, and even counties, began offering bounties for killing wolves.
In his book, “War Against the Wolf,” Rick McIntyre describes how professional “wolfers” used strychnine-laced livestock carcasses to kill wolves and collect payments. In Montana, the state veterinarian was directed to infect live wolves with mange. The wolves were released to infect other packs with the skin disease.
Western ranchers also lobbied the federal government for help eliminating wolves, arguing that newly established forest reserves and grazing lands acted as “reservoirs” for predators, McIntyre said. By 1915, the federal government was a major player in wolf extermination efforts.
Nearly 70,000 wolves were killed by the U.S. Fish and Wildlife Service and its predecessor agency, the U.S. Biological Survey. The total doesn’t include wolves killed by the Forest Service or the National Park Service, two other agencies active in wolf extermination, according to McIntyre. By 1926, Yellowstone National Park had no wolves left.
Nearly 50 years later, President Richard Nixon banned the use of strychnine and cyanide for poisoning predators. Passage of the Endangered Species Act in 1973 later signaled a national policy shift in wildlife management. Five years later, wolves in the Lower 48 states received federal protection under the act.