Neovison vison; the American Mink
Ah, the mink; first brought to the UK in 1929 to begin farming it commercially for fur, it doesn't have an easy time in its new home! The mink was first recorded breeding in the wild in 1957 and was widespread and well established by the 1970's. Its impact on native wildlife is well known today; notably that it can decimate water vole (Arvicola terrestris) populations which were already declining steeply by the time the mink started to spread. The water vole has declined by 97% since the 1950's and so control of mink is an accepted part of water vole projects but only where it is paired with longer term schemes; mink control requires intensive sustained work and territorial vacancies are often simply filled by neighbouring populations. However, both the otter (Lutra lutra) and polecat (Mustela putorius) are known 'intra-guild' competitors, with the otter even being known as a predator of the mink in other countries, and it is suspected that as the shattered populations of these two native species increases pressure will be placed on to mink, forcing it out of territories and lowering its numbers. Mink have in fact been in decline in the UK for approximately 28 years; the population estimate of 2010 was 110,000. To conclude, it must be said that fur farming, inherently an unworthy trade, has a lot to answer for in its introduction of the mink to the UK.