The wolverine is a powerful animal that resembles a small bear but is actually the largest member of the Mustelidae (weasel) family.
The wolverine lives in the remote Arctic and sub-Arctic regions of the world.
Wolverines live primarily in isolated regions of northern Canada, Alaska, Siberia, and Scandinavia; they are also native to European Russia, the Baltic countries, the Russian Far East, northeast China and Mongolia.
Their habitats include Alpine forests, boreal forests, grasslands, tundra and rocky areas (inland cliffs and mountain peaks).
Wolverines have an average lifespan between 7 and 12 years in the wild.
The adult wolverine is about the size of a medium dog, with a length usually ranging from 65–107 centimeters (26–42 inches), a tail of 17–26 centimeters (6.7–10.2 inches), and a weight of 9–25 kilograms (20–55 pounds).
The males are as much as 30 percent larger than the females.
Anatomically, the wolverine is a stocky and muscular animal. With short legs, broad and rounded head, small eyes and short rounded ears. Though its legs are short, its large, five-toed paws and plantigrade posture facilitate movement through deep snow.
Wolverines have thick, dark, oily fur which is highly hydrophobic, making it resistant to frost.
Wolverines are solitary creatures, and they need a lot of room to roam. Individual wolverines may travel 24 kilometers (15 miles) in a day in search of food.
Wolverines have poor eyesight, but their senses of hearing and smell are excellent, which help them find the prey more easily.
The wolverine is a powerful and versatile predator and scavenger. They easily dispatch smaller prey, such as rabbits and rodents, but may even attack animals many times their size, such as caribou, if the prey appears to be weak or injured. These opportunistic eaters also feed on carrion — the corpses of larger mammals, such as elk, deer, and caribou.
The powerful jaws and large teeth of the wolverine are able to demolish frozen carrion and bones.
Their diets are sometimes supplemented by birds’ eggs, birds (especially geese), roots, seeds, plants, berries and insect larvae.
Although wolverine are primarily nocturnal, diurnal movement is often recorded.
Wolverines are territorial animals and defend large, gender-exclusive territories. Their territories can range from 65 kilometers (40 miles) to more than 600 kilometers (372 miles).
The wolverine is very quick and can run at speeds of up to 50 kilometers (30 miles) per hour when chasing its prey.
Wolverines are typical terrestrial animals, but they can also climb trees and swim when needed.
They do not hibernate and are well-adapted for winter existence, with extremely dense fur, large snowshoe-like paws that allow them to stay on top of deep snow, and crampon-like claws that enable them to climb up and over steep cliffs and snow-covered peaks.
Wolverines prefer colder areas also because they use the snow for dens, besides food storage.
Wolverines are polygamous. Successful males will form lifetime relationships with two or three females, which they will visit occasionally, while other males are left without a mate.
They mate from May to August. After mating, females create dens in which to have their young. These dens are often caves dug in the snow and can be up to 4.5 meters (15 feet) deep.
The gestation period is 30–50 days, and litters of typically two or three young (“kits”) are born in the spring. Kits are born with their eyes closed and are covered in white fur. While the females handle the bulk of the rearing, males will visit from time to time and care for the young.
Kits develop rapidly, reaching adult size within the first year. Sometimes, kits will stay with their mother until they are ready to have kits of their own. Wolverines are ready to reproduce at around 2 years old.
During the 19th century, wolverine populations nearly disappeared due to hunting and other human activities like deforestation and recreational use of their habitats.
Today, they are protected in several areas and their number in the wild is stable.
The biggest threat to wolverines is climate change. Warmer weather could mean less snow, which wolverines are dependent becouse females burrow in the snow.
Wolverines are also referred to as the glutton, carcajou, skunk bear, or quickhatch (of Native American origin).
The wolverine’s scientific name, Gulo gulo, comes from the Latin word gulo, which meaning glutton.
The wolverine has a lumbering gait as its head and tail are lower than its arched back.
The wolverine’s sense of smell is uncanny — it can detect a carcass lying 20 feet (6 meters) under the snow, allowing it to find the remains of animals killed in avalanches.
Wolverines possess a special upper molars in the back of their mouth that are rotated 90 degrees inward, allowing animal to tear apart the flesh of the prey quickly.
They were hunted in the past because of their thick and water-resistant fur which was used as lining for parkas.