Fauna
Mammal

Least Weasel

Mustela nivalis

Also known as Little Weasel, Common Weasel

Least weasels are the world's smallest carnivorans, burning energy so rapidly that they must consume up to half their body weight in food every day. Their long, slender bodies enable them to pursue voles and mice directly into tight underground burrows. In northern latitudes, these hyperactive predators shed their brown summer fur for pure white winter coats to stay camouflaged in the snow.

CarnivoreSmall MammalAgile
Least Weasel reference
Keven Law / CC BY-SA 2.0 · cc-by-sa
—observations
—countries
—peak records
Least ConcernConservation statusIUCN Red List categoriesLCNTVUENCREWEXLeast ConcernRed List categories, explained →
Key facts
Diet & preyVoles, Mice, Shrews
Predators
  • Owls
  • Hawks
  • Foxes
ThreatsHabitat loss, rodenticide poisoning, predation by raptors
HabitatsGrasslands, open forests, tundra, farmland, scrublands
Life span1–3 years in the wild
Classification
  1. FamilyMustelidae
  2. SpeciesMustela nivalis
Range & activity
Range data is not available yet.
Safe observation
Interaction riskLow
  1. Low
  2. Moderate
  3. High
  4. Very high
Why interaction risk is low
Capable of a sharp bite if cornered or handled; observe from a respectful distance.
Why it is dangerous
Delivers a painful bite with sharp teeth when cornered or restrained.
How to recognize a risky encounter
Tiny, tube-shaped body with reddish-brown upperparts, white belly, and short tail lacking a black tip.
What to do
Do not attempt to touch or trap wild individuals; leave clear escape routes open.
Responsible observation
  • Spotting: Scan stone walls, log piles, and field margins where rodents nest.
  • Behavior: Expect rapid, jerky movements as they dart between patches of cover.
Related species
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