American Mink Mustela vison
The American mink – known for its thick, dark, glossy fur – is an introduced predator that is very much out of place among the fauna of Norfolk and has a detrimental effect on the surrounding native wildlife.
Conservation status in Norfolk
These animals, descendants from mink that escaped or were intentionally released from fur farms, are an ‘alien’ species and do not fit properly into Norfolk’s ecology. The American mink is a very undesirable resident in Norfolk and certainly not to be encouraged; in fact, due to the damage the animal can cause to native wildlife, especially species such as the water vole, the Norfolk Biodiversity Partnership is undertaking ongoing control programmes in mid-Norfolk and the Broads. Gamekeepers also undertake mink control in order to reduce predation of pheasants and partridge, all of which contributes to the control of this predator.
Mink also hunt water birds, such as moorhen and ducks, and a noticeable decline in numbers of birds may indicate that mink are in the area. Mink are aggressive predators and will overkill prey. They can cause significant damage to housed or penned game birds or poultry by killing large numbers, far more than they can eat, and they may also damage fish stocks.
Mink also predate the endangered water vole. One reason that mink cause such a problem for the species is that female and young mink are small and agile enough to follow a water vole into its burrow.
It used to be thought that mink displaced otters and were part of the reason for the otters’ decline. However, this is now thought not to be true, and although there is evidence that sometimes otters will actually kill mink, mink and otters co-exist throughout Norfolk.
How to help
Paul Gambling
Information on the American Mink
How to recognise
The non-native American mink is in the same mammal family as the otter, stoat and weasel, and resembles all of these species in general body shape. It is quite commonly confused with the otter, especially in wetland habitats, but there are several important differences. It has a long, slim body, short legs and a round, fluffy tail that is about a third of its body length. The otter’s tail is broad-based, flat, tapers towards the tip, and is about half the body length. In size American mink are larger than stoats and weasels but smaller than a domestic cat and about half the size of an otter. The average body length is 60cm for males and 50cm for females. The tail adds an extra 14-21cm. The fur is rich, glossy and generally dark brown or black, with a white or pale patch on the chin only. The pale markings on an otter extend from the chin to the chest. The muzzle of a mink is pointed and ferret-like whereas the otter has a flattened head shape and a broad dog-like muzzle. The mink swims high in the water with the head and body visible but the otter swims low in the water with only the head and part of the tail on show.
The endangered and smaller European mink is not found in the UK and so is unlikely to be confused with its larger American cousin.
Where to see
Mink can be found in and around many Norfolk waterways, including many parts of the Broads and rivers including the Waveney Valley, but their elusive nature makes them very difficult to see. They can also be found away from waterways provided prey, such as rabbits, other small mammals and birds, is available.
When to see
Mink can be seen throughout the year but generally require either patience or luck to actually spot them. They are active throughout the day but are most likely to be seen between dawn and dusk.
Did you know?
The American mink has a stronger odour than the skunk!
Related questions
How do I tell the difference between a mink and an otter?
The non-native American mink is in the same mammal family as the otter, stoat and weasel, and resembles all of these species in general body shape. It is quite commonly confused with the otter, especially in wetland habitats, but there are several important differences. It has a long, slim body, short legs and a round, fluffy tail that is about a third of its body length. The otter’s tail is broad-based, flat and tapers towards the tip and is about half the body length. In size American mink are larger than stoats and weasels but smaller than a domestic cat and about half the size of an otter. The average body length is 60cm for males and 50cm for females. The tail adds an extra 14 – 21cm. The fur is rich, glossy and generally dark brown or black, with a white or pale patch on the chin only. The pale markings on an otter extend from the chin to the chest. The muzzle of a mink is pointed and ferret-like whereas the otter has a flattened head shape and a broad dog-like muzzle. The mink swims high in the water with the head and body visible but the otter swims low in the water with only the head and part of the tail on show.
Why are American mink a problem?
These animals, descendants from mink that escaped or were intentionally released from fur farms, are an ‘alien’ species, and don’t fit properly into Norfolk’s ecology. The American mink is a very undesirable resident in Norfolk and certainly not to be encouraged; in fact, due to the damage the animal can cause to native wildlife, especially species such as the water vole, the Norfolk Biodiversity Partnership is undertaking ongoing control programmes in mid-Norfolk and the Broads. Gamekeepers also undertake mink control in order to reduce predation of pheasants and partridge, all of which contributes to the control of this predator.
Mink also hunt water birds, such as moorhen and ducks, and a noticeable decline in numbers of birds may indicate that mink are in the area. Mink are aggressive predators and will overkill prey. They can cause significant damage to housed or penned game birds or poultry by killing large numbers, far more than they can eat, and they may also damage fish stocks.