U.S. Department of Agriculture: Animal and Plant Health Inspection Service


Date of this Version

July 2001


Published in Endangered Species UPDATE.


Gray wolf (Canis lupus) populations were eliminated from Montana, Idaho, and Wyoming, as well as adjacent southwestern Canada by the 1930s. After human-caused mortality of wolves in southwestern Canada began to be regulated in the 1960s, populations began expanding southward. Dispersing individuals occasionally reached the northern Rocky Mountains of the United States, but lacked legal protection there until 1974, after passage of the Endangered Species Act of 1973. In 1986, wolves from Canada successfully raised a litter of pups in Glacier National Park, Montana, and a small population was soon established. In 1995 and 1996, wolves from western Canada were reintroduced to remote public lands in central Idaho and Yellowstone National Park. These wolves were designated as nonessential experimental populations to increase management flexibility and address local and state concerns. Wolf restoration is rapidly occurring in Montana, Idaho, and Wyoming, and there were at least 28 breeding pairs in December 2000. There are now about 63 adult wolves in northwestern Montana, 192 in central Idaho, and 177 in the Greater Yellowstone area. Dispersal of wolves between Canada, Montana, Idaho, and Wyoming has been documented. Occasional lone wolves may disperse into adjacent states, but population establishment outside of Montana, Idaho, and Wyoming is probably not imminent. The gray wolf population in the northwestern U.S. should be recovered and, depending on the completion of state and tribal wolf conservation plans, could be proposed to be removed from Act protection within three years. Wolf restoration has proceeded more quickly and with more benefits, such as public viewing than predicted. Problems, including confirmed livestock depredations, have been lower than estimated. The Service led interagency recovery program focuses its efforts on achieving wolf recovery while addressing the concerns of people who live near wolves. Wolves have restored an important ecological process to several large wild areas in the northern Rocky Mountains of the U.S. The program has been widely publicized and is generally viewed as highly successful.