Small Weasels

The small weasels are some of our most beneficial predators, eating mice and other rodents that can cause problems to agriculture.

Least Weasel (Mustela nivalis)
least weasel

Size

  • Is the smallest living carnivore.
  • Body length is 20 centimetres (8 inches).
  • Weight is 70 grams (2.5 ounces).

Appearance

  • Tail is short, and lacks a black tip.
  • Feet are white.
  • In winter, body is completely white.

Distribution

  • Is found in all natural regions in Alberta.

Food

  • Its small size enables it to readily capture mice, shrews and pocket gophers in their burrows and snow tunnels.
  • It also eats insects.

Reproduction

  • May give birth to three to five young during any month of the year.

Status

The least weasel is classified as Secure in the current General Status of Alberta Wild Species report. See:

Short-tailed Weasel (Mustela erminea)

Size

  • Body length is 33 centimetres (13 inches).
  • Weight is 170 grams (6 ounces).

Appearance

  • Tail has a black tip.
  • Feet are white.
  • Coat is brown in the summer and white in the winter.
  • Its smaller size and white feet distinguish this species from the long-tailed weasel (see below).

Distribution

  • Is found in all natural regions except the grassland.

Reproduction

  • Mating usually occurs in July or August.
  • Four to eight young usually arrive in April or May.

Status

The short-tailed weasel is classified as Secure in the current General Status of Alberta Wild Species report. See:

Long-tailed Weasel (Mustela frenata)
least weasel

Size

  • Body length is 45 centimetres (16 inches).
  • Weight is 340 grams (12 ounces).

Appearance

  • Tail has a black tip.
  • Feet are brown.
  • Despite its wide range (see Distribution below), only northern populations of the long-tailed weasel turn white in winter.

Distribution

  • Preferring open country, the long-tailed weasel inhabits the parkland and grassland natural regions in Alberta.
  • Its North American range includes the United States and Mexico.

Reproduction

  • Mating usually occurs in August.
  • Four to eight young are usually born in late April.

Status

The long-tailed weasel is classified as May Be at Risk in the current General Status of Alberta Wild Species report. Its population has experienced dramatic declines and disappearance from some areas as a result of habitat loss and fragmentation. See:

 

Page Information

Updated: May 13, 2010