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.

Fossil bones of the animal have been found in two caves in County Cork, with one set dating back between 27,000 and 35,000 years and a second set around 10,680 years ago. There is compelling evidence that the species survived the last Ice Age under the snow, making it one of our oldest mammal inhabitants, along with 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.

Yes, 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

Your sightings are invaluable — If you see an Irish stoat, submit your sightings via the National Biodiversity Data Centre. By participating in Citizen Science, you’ll help fill critical knowledge gaps.