The wolverine (or
carcajou in French) is the largest terrestrial
member of the
Mustelidae, the
weasel family. They are
adapted to survival in extreme northern habitats, and are
powerful predators. The wolverine can be found throughout northern
Canada and
Scandinavia.
General biology and behaviour
The wolverine has a
passing resemblance to some
bears, but upon seeing
the animal move there is no mistaking its relation to other members of the
weasel family. They are powerfully built animals, with heavy
skulls and
very developed
teeth. Males generally weigh about 15 kg, while females
are somewhat smaller at 8-10 kg. Their brown
fur is thick and longer on
the tail than the rest of the body. Frequently, the fur near the toes and
face is a lighter colour, often becoming completely white.
Wolverines are remarkable predators, preying principally upon
ungulates like deer, moose or caribou. While they are capable of
killing live deer, the majority of their ungulate consumption occurs as a
result of scavenging. In the winter months when ungulate prey
are not available, like wolves the wolverines rely upon local
rodent populations to supplement their diet. Their scavenging lifestyle
puts them at times into direct conflict with mountain lions and wolves.
These two species are known to prey upon adult wolverines, and likely the
young. Given the extent to which female wolverines go to secure nests
for their kits, biologists believe that the risk of predation
on young wolverines must be quite high.
Wolverines are highly territorial animals, patrolling home ranges on
the order of 400 to 1500 square kilometers. As a result of their huge home
ranges, wolverine densities, even in optimal habitats, are
quite low, making them susceptible to extirpation (see
Conservation status). The size of the home range is supposedly
negatively correlated to prey abundance, and some scattered
evidence supports this contention. Also, the home range size and position
for males is directly related to the home ranges of females of
reproductive age.
Wolverines communicate with one another by using
vocalizations and marking their territories.
They can scent their territories using both their urine and
abdominal rubbing. While they, like most mustelids, have anal
glands, their musk is used mostly for defense rather than
communication.
Wolverines are distributed circumpolarly. They can be found in the
northern parts of Canada in the taiga or tundra, but can also be found
at high elevations further south. There are extant southern populations
in British Columbia, Montana and Idaho. In Eurasia, they are found
throughout Scandinavia and east to Siberia and Asia. Unlike most other
northern species, however, they do not hibernate.
Both male and female wolverines attain sexual maturity relatively
quickly (15 months for the females, 24 months for the males). Wolverines
do not form breeding pairs like wolves, but some evidence suggests that
males may remain in a female's territory to help with the early care of
the young. Females go into heat once per year (they are monestrous)
and breeding takes place from May to August. Males begin to have elevated
testosterone levels and sperm production by early April, but they
revert to a non-breeding state by August. Unlike many animal species,
the female initiates copulation. After fertilization, the eggs remain at
the blastocyst stage for several months. Further embryonic development
does not begin until November or December and females give birth the
following March or April. 2-3 kits are produced per average litter, and
feed from their mother for roughly 10 weeks. After weaning, they remain
with their mothers for a number of months before leaving to begin their
solitary existence.
Conservation status
Given the very low densities and large home ranges of wolverines (see
General biology and behaviour), the species is one at considerable
risk of extinction by humans. Not only
habitat destruction but also
habitat fragmentation have resulted in
extirpation of local
populations. Not only do wolverines need considerable areas to survive,
but these areas must also be
uninterrupted by
human influences.
Forestry and
mining in northern reaches negatively influence
wolverines in three ways. First, they
perturb the habitat, removing
forest stands and low-lying vegetation preferred by wolverines. Second,
their presence reduces the density of ungulates, meaning there are fewer
prey for the wolverines. Third, the construction of access roads
significantly modifies the movement patterns of wolverines, thus reducing
their ability to find one another,
mate and
forage for food.
Humans also trap wolverines for their pelts. Trapping is legal in
British Columbia, Alberta, Alaska and Montana, despite the low
densities reported for the species. They are considered endangered in
eastern Canada, threatened in Western Canada and the United States, and
have been listed by CITES in some Scandinavian countries. It is also
listed as vulnerable by the IUCN.
Importance to humans
Wolverines have been trapped by humans for hundreds of years for their
lush, warm
pelts. They have also been targeted by trappers due to the
fact that they often
raid previously laid traps and steal the
carcasses for food.
They are animals of some importance to the spiritual lives of the
Innu. The wolverine (Kuekuatsheu) is seen to be a highly
intelligent but foolish trickster, and plays a role in many Innu
myths and stories.
Taxonomy
Order:
Carnivora
Family:
Mustelidae, the
weasels
Subfamily:
Mustelinae
Genus,
species:
Gulo gulo1
1Some scientists believe that there are sufficient
morphological differences between wolverine
populations to justify the creation of three
subspecies: the Old World
wolverine,
Gulo gulo gulo, the New World wolverine,
G. g.
luscus, and the
Vancouver Island wolverine,
G. G.
vancouverensis.
Just a quick note about two of the w/u's above.
Sudderth is incorrect in
claiming that the wolverine was desended from wolves; they have completely
separate evolutionary histories, and are related only inasmuch as they are
both members of the order
Carnivora. And
Cobra Rax states that
the French call the animal
Glouton and while that is a synonym, it
is more often known as the
carcajou, which
Stavr0 tells me is derived from the Innu name
Kuekuatsheu.
Information culled from ...
* http://www.wolverinefoundation.org
*
http://www.predatorconservation.org/predator_info/Forest_Clearinghouse/Wolverine/buecking1998.htm
* http://www.innu.ca/myth.html