Gray wolves, also known as timberwolves, were relentlessly hunted in the 1800s and early 1900s to keep them from preying upon farm animals. By 1960, considered the low point for the wolf population in the contiguous United States, there were only 350 to 700 wolves in the entire nation, most of them in extreme northeastern Minnesota and a few more on Isle Royale in Lake Superior, according to the International Wolf Center.
Wolves were one of the first animals listed in the Endangered Species Preservation Act of 1966, the precursor to the Endangered Species Act that would be approved three years later. They were listed as endangered in every state except Minnesota, where they were listed as threatened, according to a report by the Congressional Research Service, a branch of the Library of Congress. Wolves were added to the endangered list in Washington state in 1980.
As of late 2011 there were about 6,000 wolves in the 48 contiguous United States, according to the U.S. Fish and Wildlife Service. All of those listed are in the Great Lakes region, Minnesota, the mountain Northwest and Southwest. In Alaska, where the wolves have not been protected by the Endangered Species Act, there were between 7,700 and 11,200 wolves in 2010.
Now, because of their recovery, gray wolves have been removed from federal protection in the Great Lakes region, Minnesota, Idaho, Montana, Wyoming and in parts of Eastern Washington. They are still listed as endangered in the western two-thirds of Washington.