Keywords Mammals

Description Weasels have dark brown upper bodies and tails; creamy white to orangish underparts. They assume a white winter coat in northern regions. In the FUR INDUSTRY no distinction is made among the coats of the 3 species; all are marketed as ermine. The weasel's head is bluntly pointed; ears, small and rounded. The long, slender body has a thick neck and short feet.

Distribution and Habitat Weasels occur throughout mainland Canada from interior BC to northern Ontario and Québec. They prefer coniferous FOREST or TUNDRA but also inhabit marshes, meadows and broken woodlands. Long-tailed weasels, the largest species, occur from S America to about 49° N lat and are found in southern BC, the PRAIRIES, Ontario, Québec and NB. They prefer mixed hardwood forest but also inhabit other forests or open country, always near water.

The short-tailed weasel, widespread in the northern hemisphere, occurs throughout Canada in habitats including tundra, BOREAL FOREST, meadows and river banks. All species take small mammals and INSECTS; long-tailed and short-tailed weasels also take young RABBITS and larger rodents.

Reproduction and Development Long-tailed weasels breed in July-Aug; 4-9 young are born 205-237 days later. Delayed implantation of the embryo accounts for the long gestation. Short-tailed weasels mate in March; gestation lasts about 30 days; the single litter averages 6 young. Least weasels bear 2-3 litters annually, each of 3-6 young; gestation lasts about 35 days. Males may assist females in hunting food for young.

Relationship with Humans As efficient killers of MICE, weasels are useful to farmers, except when they take poultry.

Black-footed Ferret (Side View)
The black-footed ferret is likely the rarest land mammal in North Amercia (artwork by Todd Telander).

Marten
The marten is an acrobatic weasel, spending much of its time in trees (artwork by Todd Telander).

River Otter
Sea otters live on the wooded slopes of watercourses (artwork by Todd Telander).

Weasel, Short-tailed
Weasels assume a white winter coat in northern regions (artwork by Claire Tremblay).

Fisher
The fisher is a solitary hunter, secretive and seldom seen (artwork by Todd Telander).

Author C.S. CHURCHER

Links to Other Sites
Canadian Biodiversity Website
A great information source for all budding biologists. Learn about biodiversity theory, natural history, and conservation issues. From McGill’s Redpath Museum.