The wolf belongs to the family "Canidae". The gray, or timber, wolf is known as "Canis lupus". The red wolf is known as "Canis rufus".

The gray, or timber wolf, once widely distributed but now found only in Canada, Alaska, and northern Europe and Russia, except for a few isolated packs in America. The red wolf, is found only in Texas and the southeastern United States.

Wolves exist in smaller numbers in the Pacific Northwest and upper Midwest, primarily in Minnesota. Under the Endangered Species Act, the gray wolf is listed by the United States and Wildlife Service (USFWS) as threatened in Minnesota and as an endangered species elsewhere in the United States except Alaska.. The red wolf, also listed as endangered species, was the first species that the USFWS developed a recovery plan for.