There are two specials of wolves: the gray, or timber wolf, once widely distributed but now found only in Canada, Alaska, and northern Europe and Russia, exempt for a few isolated packs in other regions; and the red wolf found only in Texas and the Southeastern United States.

  An adult gray wolf measures up to 2 m in length, including the tail and weighs up to 80 kg. The fur of the gray wolf is red-yellow or yellow-gray with black patches on its back and sides, and white on its chest and abdomen. There are also black or brown gray wolves, and those in the far north may be pure whites. The red wolf is smaller in size and usually darker in color.

  Wolves are equally at home on prairies, in forests lands and on all but the highest mountains. In the winter they travel in packs searching for food. Small animals and birds are usually the common prey of wolves, but a pack sometimes attacks reindeer, caribou, sheep and other large mammals, usually selecting weak, old and very young animals for easier capture. When no live prey can be found, wolves feed on carrion. They also eat berries.