Russian mink, European mink, Russian mink, Eurasian mink
The European mink (Mustela lutreola ), also known as the Russian mink and Eurasian mink, is a semiaquatic species of mustelid native to Europe.
It is similar in colour to the American mink, but is slightly smaller and has a less specialized skull. Despite having a similar name, build and behaviour, the European mink is not closely related to the American mink, being much closer to the European polecat and Siberian weasel (kolonok ). The European mink occurs primarily by forest streams unlikely to freeze in winter. It primarily feeds on voles, frogs, fish, crustaceans and insects.
The European mink is listed by the IUCN as Critically Endangered due to an ongoing reduction in numbers, having been calculated as declining more than 50% over the past three generations and expected to decline at a rate exceeding 80% over the next three generations. European mink numbers began to shrink during the 19th century, with the species rapidly becoming extinct in some parts of Central Europe. During the 20th century, mink numbers declined all throughout their range, the reasons for which having been hypothesised to be due to a combination of factors, including climate change, competition with (as well as diseases spread by) the introduced American mink, habitat destruction, declines in crayfish numbers and hybridisation with the European polecat. In Central Europe and Finland, the decline preceded the introduction of the American mink, having likely been due to the destruction of river ecosystems, while in Estonia, the decline seems to coincide with the spread of the American mink.
European minks are small carnivores once widely distributed over almost the whole of the European continent and currently surviving in a few enclaves as fragmented populations. The huge change in its numbers and distribution means it is one of the most endangered mammals of Europe and the world.
100 years ago this mink species occurred throughout the continent of Europe, but populations of them have declined severely and it is now either extinct or vastly reduced in most of the range it inhabited formerly. It survives only in small populations in regions of Eastern Europe (Romania, Russian Federation, Ukraine) and Spain and France. This species thrives in densely-shaded banks in fresh water rivers, creeks and lakes. They may build their own burrows, move into an evacuated Water vole burrow, or live in a crevice among trees roots.
European minks are solitary wanderers, with large home ranges as large as 15 kilometers of river. They rarely use the same den, the female usually staying close to the den, except when a food shortage drives her to find another site. An individual will use a permanent burrow as well as temporary shelters, the permanent one used all year round except during floods, being 6–10 m from the edge of the water. This species is somewhat sedentary and confines itself in its burrow for long periods during very cold weather. The European mink lives a solitary life, except during the mating season. Around dusk and before sunrise are their most active times.
A European mink is a carnivore and opportunistic predator and mainly eats rabbits, rates, birds, fish, crayfish and frogs. They may also eat insects and vegetation.
Little is known about the mating system of European minks, however, as they lead a solitary life and meet only to mate, it may suggest the animals exhibit a polygynous mating system. The mating season is from February to March. Gestation is about 35-72 days, and births occur in April and May. A litter numbers between two and seven, and usually is about four or five. The young can open their eyes at 4 weeks and their teeth appear within 15-17 days, being replaced with adult teeth at 60-72 days. Weaning takes place at about 10 weeks, when they begin tracking and catching prey. At 56–70 days they go with their mother on hunting expeditions, and become independent at 70–84 days. European minks reach reproductive maturity at about 1 year.
Populations of this species have suffered a series of commercial and ecological threats. In parts of Europe, serious threats facing this sensitive species are habitat loss and degradation, due to the significant increase during the past decades of water pollution and hydroelectric developments. Another major threat is commercial trapping for the animal’s fur. Accidental deaths due to pest control trapping and poisoning occur, as well as vehicle collisions, particularly frequent in the west of this species’ range. Furthermore, all mink species are susceptible to Aleutian disease, which causes persistent infection, is highly contagious and often is lethal.
According to the Animal Diversity Web (ADW) (University of Michigan) resource, the world total populations size of the European mink is less than 30,000 individuals. This includes approximately 25,000 European minks in Russia, approximately 2,000 minks found in France and approximately 1,000 minks in northern Spain. According to the IUCN Red List, the Russian population of European mink has been estimated at about 20,000 individuals; Spain holds near 500 individuals; in Romania - 1,000-1,500 individuals; Estonia - fewer than 100 individuals on Hiiumaa Island. Overall, currently European minks are classified as Critically Endangered (CR) on the IUCN Red List and their numbers today are decreasing.