The Wolverine (Gulo gulo) is the largest land-dwelling species of the weasel family Mustelidae. It is also known as the Glutton or Carcajou. The wolverine lives primarily in isolated areas in the northern hemisphere. These areas include Alaska, northern Canada, Siberia and Scandinavia. They are also native to Russia and the Baltic countries. Until the mid 1800’s they were found as far south as northern California. Some still remain in the Rocky Mountains and northern Cascades in the United States.

The wolverine is a stocky and muscular animal, considered carnivorous but known on occasion to eat plant material. It has glossy brown hair with stripes of dull yellow along the sides. Its fur is long and dense and does not retain much water, making it very resistant to frost that is common in the wolverine’s cold habitat. (For these reasons, the fur has been traditionally popular among hunters and trappers as a lining in jackets and parkas). The adult wolverine is about the size of a medium dog, with a length usually ranging from 25-34 inches, a tail of 7-10 inches, and weight of 22-55 pounds. Males are nearly three times larger than females.

In appearance the wolverine resembles a small bear with a long tail. It has been known to give off a very strong, extremely unpleasant odor, giving rise to the nicknames “skunk bear” and “nasty cat.” Wolverines, as well as other Mustelidae, possess a special upper molar in the back of the mouth that is rotated 90 degrees, or sideways. This special characteristic allows wolverines to tear off meat from prey or carrion that has been frozen solid and also to crush bones enabling the wolverine to extract marrow. Wolverines are remarkably strong and are considered one of the most ferocious in their family.

Mating season is in the summer, but the actual implantation of the embryo in the uterus is stayed until early winter, delaying the development of the fetus. Females will often not produce young if food is scarce. The young (typically three or four) are born in the spring. Kits develop rapidly, reaching adult size within the first year of a lifespan that may reach anywhere from five to thirteen years. They have no known natural predators, although they can be attacked by larger animals (bears) over food sources.