Wolverine

Order: CARNIVORA
Family: MUSTELIDAE
Genus: GULO
Species: GULO

The wolverine is the largest member of the weasel family Mustelidae and, though formerly classified as its own New World species, luscus, it is usually classed as the same species found in Eurasia, gulo. Wolverines are known by several colloquial names. The genus and species name “gulo” means “The Glutton” referring to its reputation as a ferocious slayer and consumer of all it encounters. “Skunk-bear” alludes to the wolverines resembling small bears, skunk like body striping, and habit of marking food sources with musk and/or urine. The Cree called them “Ommeethatsees” meaning “one who likes to steal” relating the wolverines=92 reputation for raiding traps/trap lines, human food caches, and cabins. As with many colloquialisms, there is some basis in reality and some degree of exaggeration in these names.

The wolverine is a stout, thick bodied, short-legged weasel weighing 20 to 60 pounds and measuring from 30 to 45 inches long including its 7 to 9 inch, bushy tail. As with most members of the weasel family, there is significant sexual dimorphism in body size with males averaging about 10% longer of body and 30% heavier. This sexual dimorphism decreases with increasing latitude. Wolverines are described as dark brown with prominent, broad, yellowish buff stripes from shoulder to rump on both sides of the body sometimes extending onto the tail. They also often have white to yellow headbands, collars, and/or socks that can aid in the identification of individuals. The wolverine generally walks heel to toe in a plantigrade fashion with 5 toes usually, but not always, registering in the 3-4 inch wide by 4-5 inch long track. Common gaits include an alternating direct register at a walk, 3 and 4 print lopes, and, less often, the mustelid 2×2, bounding pattern.

Wolverines cover an average of about 15 miles per day (except females with kits) searching for food and marking their territories primarily at night. Territories range from about 50 -500 sq. miles; males generally having notably larger territories than females and often overlapping the territories of a few to several females but not of other males. Communication and territory marking is accomplished primarily by urination and secondarily by musk from anal, plantar (back feet), and abdominal glands. Low population densities are thought to be the norm but recent studies indicate that “The Glutton” is probably not as solitary as once thought. Wolverines prefer high mountain wilderness often including the alpine zone, taiga, or tundra and coastal regions in the more northern latitudes of their range. They are circumpolar existing in the northern latitudes of both the Eurasian and North American continents. On the N. American continent, they are believed to range in parts of CO, CA, OR, WA, ID, MT, WY, AK, and most of the provinces of Canada. There is evidence that they once roamed the montane zones of AZ and NM, pre-European settlement of this continent. Their distribution seems to be directly associated with the presence of large mammals as carrion food resource (i.e. ungulates or sea mammals.)

The “skunk-bear” is especially carniverous with ungulate and sea mammal carrion being of critical importance in their diet. They will actively predate small mammals like snowshoe hares, birds like ptarmigan, and, opportunistically, large mammals that are injured or bogged down in the snow. When available, wolverines will also eat significant amounts of berries and insect larvae. These big weasels are infamous for raiding traps for the bait (=3Dcarrion), human food caches, and cabins and are known to haunt avalanche chutes for carrion that may be found buried in the snow. They have a great nose for detecting food buried deep in the snow, powerful musculature and claws well suited for digging through snow and ice, and powerful jaws capable of crushing large ungulate femurs (as moose) and tearing frozen meat. Wolverines are also known for caching food and scent marking food caches.