Although they are called by different names in Canada, Alaska, Scandinavia and Russia, most northern wolves are considered to be a single species of Gray wolf Canis lupus.
The gray wolf is the largest living member of the family Canidae. Largest individuals tend to occur in the northern forests of North America, with weights of 79 kg having been recorded. A weight of 45 – 57 kg is much more typical, however.
The specimen on the right is a tundra wolf Canis lupus albus, found in the boreal forests of western Russia and northern Scandinavia.
Gray wolves from warmer and drier parts tend to be somewhat smaller. In general, there is a wide size range among the various “subspecies” of gray wolf. Equally variable is the colouration. In fact, many “gray” wolves are not gray at all. They can be solidly white or solidly black, and virtually every hue within the gray, brown, and tan spectrums.
The specimen on the right is an arctic wolf Canis lupus arctos, found in northernmost latitudes. The black one below is a member of a race from farther south. Generally, the fur of a wolf tends to be heavily mottled with various shades. Many wolves have a large, dark patch on their back which contrasts with their dominant coat colour. Contrasting dark and light facial markings are also common. A wolf’s tail is often black at the tip.
Also occurring in wolves is albinism, the lack of pigmentation in an animal. However, as is the case with virtually all mammalian species, instances of truly albino wolves (with pink eyes) are exceptionally rare. Colouration is not especially useful in classifying gray wolves, since it is such a highly variable characteristic, even within individual packs or litters. Regardless of the colouration of the parents, a wolf litter can contain pups of a multitude of hues.
Black variation Gray wolves have been divided up into various races according to the region of the world in which they live. Classification into these “subspecies” groups is a topic much debated by taxonomists, as it is considered something of a redundancy by many. Over time, species which possess wide natural ranges such as wolves, foxes, man, and many others tend to branch into geographical groups which have unique characteristics and natural histories. These groups become what are known as “subspecies” within the species.