# Stoat (*Mustela erminea*) > The stoat (Mustela erminea) is a small, slender carnivore of the weasel family found across the Northern Hemisphere in woodland, farmland, and tundra. Weighing just 200 to 400 g and about 30 cm long, it is a fierce, agile hunter of rabbits, rodents, birds, and eggs. In the far north its brown coat turns pure white in winter, when it is known as ermine. Stoats live 4 to 7 years and are listed as Least Concern. - **Category:** Mammal - **Conservation status (IUCN):** Least Concern - **Range:** Circumpolar Northern Hemisphere — Europe, Asia, North America; introduced to New Zealand where invasive. - **Canonical page:** https://globalanimalguide.org/animals/stoat/ - **Last reviewed:** 2026-07-16 ## Scientific classification - **Kingdom:** Animalia - **Phylum:** Chordata - **Class:** Mammalia - **Order:** Carnivora - **Family:** Mustelidae - **Genus:** Mustela ## Facts at a glance | Attribute | Value | | --- | --- | | Scientific name | Mustela erminea | | Diet | Carnivore — rabbits, rodents, birds, and eggs | | Habitat | Woodlands, farmland, and tundra across the Northern Hemisphere | | Lifespan | 4–7 years in the wild | | Weight | 200–400 g (0.2–0.4 kg); males larger | | Top speed | Up to 25 km/h (16 mph); agile climber | | Conservation status | Least Concern (IUCN) | ## Appearance and the ermine coat The stoat is a long, low-slung mammal about 30 cm in length, with chestnut-brown fur above, a creamy belly, and a distinctive black tip to its tail. It weighs only 200 to 400 g, with males noticeably larger than females. In colder regions the coat moults to pure white each winter, a form long prized in fur trade and heraldry as ermine, though the black tail-tip always remains. This seasonal change is triggered by shortening day length and provides camouflage against snow. ## A ferocious hunter For its size the stoat is one of the boldest predators in the countryside, routinely killing rabbits several times its own weight. It hunts by scent and sight, following prey into burrows and dispatching it with a precise bite to the base of the skull. Stoats are famed for 'mesmerising' rabbits with a strange, hypnotic dance of leaps and twists, which may confuse the prey long enough to close in. Their long, thin bodies let them pursue rodents right into their tunnels. ## Diet and feeding The stoat is a pure carnivore, feeding mainly on rabbits and small rodents such as voles and mice, along with birds and their eggs. It has a fast metabolism and must eat frequently, taking a large share of its body weight in food each day. When prey is plentiful a stoat will cache surplus kills to see it through leaner times. This appetite makes it a valuable natural check on rabbit and rodent numbers on farmland. ## Speed, agility and senses Stoats are quick and tireless, moving in a bounding gait and reaching around 25 km/h in short bursts. They are excellent climbers and swimmers, able to follow prey up trees or across water. Sharp hearing and a keen sense of smell guide most of their hunting. Their slim build lets them squeeze through tiny gaps, but it also means they lose heat quickly and must remain active to keep feeding. ## Breeding and life cycle Stoats have an unusual reproductive trick called delayed implantation, in which a fertilised egg pauses its development for many months before the young grow. This means females mate in summer but do not give birth until the following spring, timing the litter to the season of plenty. A litter usually numbers six to twelve kits, born blind and helpless in a den. Wild stoats generally live four to seven years, though many die much younger. ## Range, status and impact The stoat ranges widely across the woodlands, farmland, and tundra of Europe, Asia, and North America, and is listed as Least Concern by the IUCN. In its native range it is a natural part of the ecosystem and a useful control on rabbits. Where it has been introduced, however, notably in New Zealand, it has become a serious threat to ground-nesting native birds. There it is the target of intensive predator-control efforts. ## Frequently asked questions ### What is the difference between a stoat and a weasel? A stoat is larger than a weasel and always has a black tip to its tail, while a weasel's tail is short and lacks the black tip. Stoats also move with a bounding gait and can turn white in winter, when they are called ermine. ### Why does a stoat turn white in winter? In colder northern regions the stoat's brown coat moults to pure white each winter, triggered by shortening daylight. The white fur, known as ermine, camouflages it against snow, though the black tail-tip always stays. ### What do stoats eat? Stoats are carnivores that mainly eat rabbits and small rodents such as voles and mice, along with birds and eggs. They regularly kill rabbits several times their own body weight. ### How big is a stoat? A stoat is about 30 cm long and weighs only 200 to 400 g, with males larger than females. Despite this small size it is a bold predator capable of taking prey much bigger than itself. ### Are stoats dangerous? Stoats pose no real danger to people and will avoid humans. They can, however, be serious predators of poultry, game birds, and, where introduced, native wildlife. In New Zealand they are a major threat to ground-nesting birds. ### How long do stoats live? Wild stoats typically live 4 to 7 years, although many die much younger from predators and harsh conditions. Their reproduction uses delayed implantation, so young are born in spring when food is plentiful. ## Sources - [IUCN Red List — Mustela erminea.](https://www.iucnredlist.org/search?query=Mustela%20erminea&searchType=species) - [Animal Diversity Web — Mustela erminea. University of Michigan Museum of Zoology.](https://animaldiversity.org/accounts/Mustela_erminea/) --- Source: Global Animal Guide (https://globalanimalguide.org/animals/stoat/). Licensed CC BY-NC 4.0 — free for non-commercial reuse with attribution.