Species Irish stoat

Irish stoats are often called weasels. However, weasels are not present in Ireland. If you visit Britain or mainland Europe, where both species are present, the main differences are size (stoats are larger) and weasels don’t have a black tip to the tail. But, confusingly, stoats, pine martens, mink, otters and badgers all belong to the Family Mustelidae, which is also known as the weasel family!

The Irish stoat, Mustela erminea hibernica, is a unique subspecies only found on the islands of Ireland and the Isle of Man. It differs physically and genetically from stoats found in Britain and Europe — the Irish stoat tends to be smaller, it doesn’t turn white in the winter, and the line dividing the chestnut-coloured upper fur and the creamy-coloured fur on its belly is usually irregular.

Irish and Manx stoats are the same subspecies of stoat, Mustela erminea hibernica, which is only found on the island of Ireland and the Isle of Man.

A stoat fossil found in Ireland dates back to the Late Glacial Period, after the last Ice Age but before humans arrived. This is strong evidence that stoats naturally colonised Ireland and were not introduced by people. Genetic studies support this, too. Stoats in Ireland and the Isle of Man have high genetic diversity, which is typical of animals that colonise naturally and have been around for a long time. 

Irish and Manx stoats are a unique subspecies, most closely related to stoats from cold regions like Scandinavia and the Alps. This suggests they are well adapted to icy conditions and may have survived in Ireland under snow during the last Ice Age, feeding on lemmings that lived there at the time. This makes them one of Ireland’s oldest surviving mammals, alongside the Irish hare.

Stoats are often confused with other small carnivores in Ireland, including ferrets, American mink and the pine marten. Although similar in some ways, you could say ‘stoats are ‘stoatally’ different! All four species share the same long, thin body shape and short legs, but stoats differ in their much smaller size (far smaller than a cat), chestnut brown coat with creamy white underside, and the very distinctive black tip to their tail.

The black-tipped tail is the stoat's most distinctive feature, but it's not there just to look good. In an experiment conducted by Roger Powell using captive hawks and model stoats, it was observed that the models with black-tipped tails were less likely to be successfully targeted by the hawks compared to those with black spots in other areas or no black markings. This suggests that the black tip on the tail may draw away a predator’s attention from more vulnerable areas like the head and neck.

Stoats live in many habitats but are often seen darting across roads to dive into stone walls or hedgerows, which offer protection from predators. They’re active all year round, day and night, though colder days may keep them underground.

Stoats pose no significant danger to humans and pets like cats and dogs. Their natural behaviour is to avoid contact with people and much larger animals, such as cats and dogs. However, stoats can prey on birds such as chickens and take their eggs if given the opportunity. Making sure chicken enclosures are well maintained and free of gaps will prevent stoats from getting in.

Irish stoats are protected throughout the island of Ireland:

• Republic of Ireland: Wildlife Act (1976) and Wildlife (Amendment) Act 2000.
• Northern Ireland: Wildlife and Natural Environment Act (Northern Ireland) 2011

There is currently no protection of Manx stoats on the Isle of Man

Your sightings are invaluable 

• If you see stoat on the island of Ireland, submit your sightings via the National Biodiversity Data Centre.
• If you see a Manx stoat on the Isle of Man, report your sighting to Manx Wildlife Trust by emailing enquiries@mwt.im

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