 
The wolverine is a muscular carnivore about the size of a medium dog, and a very solitary animal. The wolverine has a reputation for ferocity and strength out of proportion to its size, with the documented ability to kill prey many times larger than itself. The wolverine lives in remote areas of northern boreal forests, and the subarctic and alpine tundra of the northern hemisphere. Its greatest populations are in northern Canada, the state of Alaska, northern Europe, and throughout Siberia. However, its population has steadily declined since the 19th century owing to trapping and increasing human habitation. 
The wolverine is an elongated animal that is low to the ground. It has strong limbs, a broad, rounded head, small eyes and short rounded ears. Though its legs are short, its large paws with long claws give it the ability it to climb steep cliffs, trees and snow-covered peaks easily.
Wolverines have thick, dark, oily fur which repels water and frost. It has anal scent glands used for marking territory.Wolverines have a special upper molar in the back of the mouth that is rotated 90 degrees, towards the inside of the mouth. This allows wolverines to tear off meat from prey or carrion that has been frozen solid. Wolverines are primarily scavengers; most of its sustenance is derived from carrion. Wolverines feed on it after the predator, often a pack of wolves, has finished, or simply take it from another predator. Wolverines are also known to follow wolf and lynx trails, in order to scavenge the remains of their kills. Whether eating live prey or carrion, the wolverine's feeding style appears voracious. 
The wolverine can also be a powerful predator. Its prey consists of small to medium-sized mammals, but the wolverine has been recorded killing prey such as adult deer that are many times larger than itself.Other prey include porcupines, squirrels, beavers, marmots, moles, gophers, rabbits, mice, rats, shrews, lemmings, caribou, deer, sheep, goats, cattle, bison, moose, and elk. Smaller predators are occasionally preyed on, including martens, mink, foxes, lynx, weasels, coyotes, and wolf pups. Wolverines often pursue live prey that are relatively easy to obtain, including animals caught in traps, newborn mammals, and deer, including adult moose and elk when they are weakened by winter or stuck in heavy snow. Their diets are sometimes supplemented by birds' eggs, birds (especially geese), roots, seeds, insect larvae, and berries. Wolves, black bears, brown bears, cougars, and golden eagles are capable of killing wolverines, particularly young and inexperienced ones. Grey wolves are the wolverine's most dangerous predator; when wolves move in to a wolverine's territory the wolverine will abandon it. In North America, another predator is the cougar. Wolverines try to avoid encounters with grizzly bears. 
Female wolverines burrow into snow in February to create a den, which is used until the kits are weaned in May. This fact has led to concern that global warming will further shrink the ranges of wolverine populations. Their need for large territories brings wolverines into conflict with human development, and hunting and trapping further reduce their numbers, causing them to disappear from large parts of their former ranges. |