By far the wolf is the largest member of the canid family. On average the wolf is about 30% larger than a dog. A wolf can range in size from 4.5 to 6 feet long, and stands between 2 and 3 feet high at the shoulder. The tail can range in size from 3.5 to almost 5 feet in length. The male wolf is generally 15 - 20% larger than the female.
A wolf can weigh as much as 175 pounds while the largest dog breeds weigh in at about 130 pounds. As you can see the wolf tends to be much larger than their dog cousins.
Wolves tend to be larger in the northern regions of their habitat ans smaller in the southern. This generally follows Bergman's rule of increased body size from south to north. The one major acception to this rule is the wolves of the high artice. They tend to be smaller than their Alaskan and Canadian cousins.
A wolf tends to look like a large dog with long legs and oversize paws. There is one major difference between a wolf and a dog. The wolf has a precaudal gland on the upper surrface of a wolf's tail. This feature is mysteriously missing from all dogs.
The wolf's face is broader than a dogs and quite often looks broader due to the ruff of fur below the ears. Their eyes shine a greenish orange at night when struck by light from a falshlight or headlights. Their eye color is usually a golden yellow, but can tend towards brown in some wolves.
Although they are called Gray wolves, they can actually range in color from pure white to pitch black. The predominant color is a grizzled gray. The color can cover the entire range in a single pack. L. David Mech has reported a pack comprised of 3 gray, 1 black and 1 white wolf. Stanley Young is quoted as saying in "The color of North American wolves...varies greatly, so much sothat it is relatively unimportant for scientific description of the animals."
Most wolves are a grizzled gray-brown color. But in studies of over 1200 wolves in Canada and the Kenai region in Alaska there was an average of 32% of the wolves was black. In fact Black wolves tend to be more scarce the further south you go.
Many of the wolves in the Canadian and Alaskan high Arctic are an off-white, almost a cream color. This actually provides better insulation because there are more air pockets versus pigments in the white guard hairs.
In 1795, Samuel Hearne, the explorer recorded that "the greatest part of those that are killed by the Esquimaux are perfectly white".