European Mink (Mustela lutreola)

The European mink has a greatly elongated body with short limbs, and a short tail. The European mink’s tail is shorter than that of the American mink (Neovison vison) and constitutes about 40% of the animal’s total body length. Tail length is 15.3–19 centimeters (6–7.5 inches) in males and 15–18 centimeters (5.9–7.1 inches).

The European mink has a large, broad head with short ears. The skull is less elongated than the Siberian weasel’s, with more widely spaced zygomatic arches and the mink has a less massive facial region. In general characteristics, the skull is intermediate in shape between that of the Siberian weasel and the western polecat (Mustela putorius). Overall, the skull is less specialized for carnivory than that of polecats and the American mink (Neovison vison), bearing more infantile features, such as a weaker dentition and less strongly developed projections.

There is sexual dimorphism in the European mink as males are longer than females and have longer tails. Total length for males is approximately 37.3-43 centimeters (14.7-16.9 inches), while total length of females is 31-40 centimeters (13.9-15.7 inches) on average. Tail length is 15.3–19 centimeters (6–7.5 inches) in males and 15–18 centimeters (5.9–7.1 inches). Overall weight is 440–800 grams (15-26 ounces).

The winter fur of the European mink is very thick and dense, but not long, and quite loosely fitting. The underfur is water-repellent and particularly dense compared with that of more land-based members of the genus Mustela. The guard hairs are quite coarse and lustrous, with very wide contour hairs which are flat in the middle, as is typical in aquatic mammals. The length of the hairs on the back and belly differ little, a further adaptation to the European mink’s semiaquatic way of life. The summer fur is somewhat shorter, coarser and less dense than the winter fur, though the differences are much less than in purely terrestrial mustelids. The European mink’s coat is similar to that of the American mink (Neovison vison), but the winter fur of the American mink is denser, longer, and more closely fitting than that of the European mink.

In dark colored European mink individuals, the fur is dark brown or almost blackish-brown, while light individuals are reddish brown. The summer fur is somewhat lighter, and dirty in tone, with more reddish highlights. Fur color is evenly distributed over the whole body, though in a few cases, the belly is a bit lighter than the upper parts. In particularly dark individuals, a dark, broad dorsal belt is present. The limbs and tail are slightly darker than the trunk.

The face has no color pattern, though both its upper and lower lips and chin are pure white. White markings may also occur on the lower surface of the throat, neck, chest, and stomach area. Occasionally, color mutations such as albinos and white spots throughout the pelage occur. The European mink is similar in color to the American mink (Neovison vison), but unlike the European mink, the American mink almost never has white marks on the upper lip.

SEXUAL DIMORPHISM

Longer Males

BODY LENGTH

31-43 cm. / 12-17 in.

TAIL LENGTH

15-19 cm. / 5.9-7.5 in.

BODY MASS

440-800 g. / 15-26 oz.

DENTAL FORMULA

I ³⁄3, C ¹⁄1, P ³⁄3, M ¹⁄2, ×2 = 34

LIFESPAN

10 yr.

GENERATION LENGTH

2 yr.

LOCOMOTION

Digitigrade

The European mink is a medium-sized, semiaquatic species of mustelid and a typical representative of the genus Mustela. The American mink (Neovison vison) and the extinct sea mink (Neovison macrodon) were commonly included in this genus, but in 1999 they were moved to the genus Neovison.The European mink is similar to the American mink, but with several important differences. It is similar in color to the American mink, but is slightly smaller and has a less specialized skull. Differences between its diet and that of the American mink are small. The tail is longer in the American species, almost reaching half its body length, while the tail of the European mink only makes up 40% of its body. The winter fur of the American mink is denser, longer, and more closely fitting than that of the European mink. Unlike the European mink, which has white patches on both upper and lower lips, the American mink almost never has white marks on the upper lip. The European mink’s skull is much less specialized than the American species’ in the direction of carnivory, bearing more infantile features, such as a weaker dentition and less strongly developed projections. The European mink is reportedly less efficient than the American species underwater.

Despite having a similar name, build, and behavior, the European mink is not closely related to the American mink. Genetic analyses indicate it being much closer to the western polecat (Mustela putorius), perhaps due to past hybridization, and the Siberian weasel (Mustela sibirica), being intermediate in form between true polecats and other members of the genus. The closeness between the mink and polecat is emphasized by the fact the species can hybridize. Compared to the Siberian weasel, the European mink is more compact and less thinly built, thus approaching ferrets and western polecats in build.

The European mink occasionally hybridizes with western polecat. Both hybridization and genetic introgression occur at low levels (3% and 0.9% respectively) and the hybridization is asymmetric, as only pure polecat males can mate with pure European mink females. Backcrossing and genetic introgression has been detected only from female first-generation (F1) hybrids of European mink with polecats. As such, hybridization and genetic introgression between the two species can be considered a rather uncommon event.

Currently, seven subspecies of European mink are recognized.

KINGDOM

Animalia

PHYLUM

Chordata

CLASS

Mammalia

ORDER

Carnivora

FAMILY

Mustelidae

GENUS

Mustela

SPECIES

lutreola

SUBSPECIES (7)

M. l. lutreola (Northern), M. l. biedermanni (French), M. l. binominata, M. l. cylipena (Middle European), M. l. novikovi (Middle Russian), M. l. transsylvanica (Carpathian), M. l. turovi (Caucasian)

The European mink is also known as the Russian mink and Eurasian mink as it is native to Europe and Eurasia.

The European mink’s scientific name is Mustela lutreola.

The English word weasel was originally applied to one species of the genus, the European form of the least weasel (Mustela nivalis). This usage is retained in British English, where the name is also extended to cover several other small species of the genus. However, in technical discourse and in American usage, the term weasel can refer to any member of the genus, or to the genus as a whole. Of the 17 extant species currently classified in the genus Mustela, 10 have weasel in their common names. Among those that do not are the stoat, the polecats, the ferret, and the European mink.

ALTERNATE

Eurasian Mink, Russian Mink

GROUP

Company

MALE

Boar

FEMALE

Sow

YOUNG

Cub, Kit

The historical range of the European mink extended from Finland to east of the Ural Mountains, to northern Spain and the Caucasian Mountains.

The relatively recent discovery of European mink in France in 1839 and in eastern Spain in 1951 suggests late expansion of the species to the west. Fossil finds of the European mink are very rare, thus indicating the species is either a relative newcomer to Europe, probably having originated in North America, or a recent speciation caused by hybridization. It likely first arose in the Middle Pleistocene, with several fossils in Europe dated to the Late Pleistocene being found in caves and some suggesting early exploitation by humans.

Over the last 150 years, European mink has severely declined and been extirpated or greatly reduced over most of its former range.

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 hypothesized to be due to a combination of factors, including climate change, competition with, as well as diseases spread by, the introduced American mink (Neovison vison), habitat destruction, declines in crayfish numbers, and hybridization with the western 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. In Estonia, the last wild individual was trapped in 1996. The decline seems to coincide with the spread of the American mink. In the Moscow region, the species was present in at least two locations until 1994, but a snow-tracking survey of these locations found no European minks in 1997.

The current range of the European mink consists of a few isolated fragments: in northern Spain and western France, in the Danube delta in Romania, in Ukraine, and in Russia. There is some information about the presence of the European mink also in the Romanian Carpathians.

In the Vologoda Region, considering the rapid decline of the species in the neighboring regions and the presence of the American mink (Neovison vison), it is not likely that the European mink populations will hold there for long.

In the Arkhangelsk Region, a population seems to exist in the north-west of the region, which is close to the northern limit of the range, with very low abundance. The presence of the American mink is also likely to pose a serious threat to the long-term existence there.

EXTANT

France, Romania, Russia, Spain, Ukraine

REINTRODUCED

Estonia

EXTINCT

Austria, Belarus, Bulgaria, Croatia, Czechia, Finland, Georgia, Germany, Hungary, Kazakhstan, Latvia, Lithuania, Moldova, Montenegro, Netherlands, Poland, Serbia, Slovakia, Switzerland

As a semiaquatic mustelid, the European mink has specialized habitat requirements and is rarely found more than 100 meters from freshwater.

The European mink inhabits inland wetland habitats and thrives in densely vegetated and shaded banks of freshwater creeks, rivers, deltas, and streams that are unlikely to freeze in the winter. Sometimes, during the warm season, the mink may inhabit lake-banks. They can also be found in shrub-dominated wetlands, bogs, marshes, swamps, fens, and peatlands.

There are no records of European mink presence on sea coast.

The European mink occurs from sea level to 1,120 meters.

WETLANDS

Permanent Rivers, Streams, Creeks, Waterfalls, Seasonal/Intermittent/Irregular Rivers, Streams, Creeks, Dominated Wetlands, Bogs, Marshes, Swamps, Fens, Peatlands, Seasonal/Intermittent Freshwater Lakes (Over 8ha), Permanent Inland Deltas

The European mink is a fast and agile animal, which swims and dives skillfully, but is reportedly less efficient than the American mink (Neovison vison) species underwater. It is able to run along stream beds, and stay underwater for one to two minutes. When swimming, the mink paddles with both its front and back limbs simultaneously. Its limbs are short with relatively well-developed membranes between the digits, particularly on the hind feet.

The European mink has both a permanent burrow and temporary shelters. The permanent burrow is used all year except during floods, and is located no more than 6–10 meters (6.6–10.9 yards) from the water’s edge. European mink may construct their own burrows, inhabit an evacuated burrow of a water vole, such as European water vole (Arvicola amphibius) or southern water vole (Arvicola sapidus), or may live in crevices among trees roots. The construction of the burrow is not complex, often consisting of one or two passages 8–10 centimeters (3.1–3.9 inches) in diameter and 1.40–1.50 meters (1.53–1.64 yards) in length, leading to a nest chamber measuring 48 centimeters by 55 centimeters (19 inches by 22 inches). Nesting chambers are lined with straw, moss, mouse wool, and bird feathers. The European mink is more sedentary than the American mink (Neovison vison), and will confine itself for long periods in its burrow in very cold weather.

The European mink does not form large territories, possibly due to the abundance of food on the banks of small water bodies. The size of each territory varies according to the availability of food. In areas with water meadows with little food, the home range is 60–100 hectares (150–250 acres), though it is more usual for territories to be 12–14 hectares (30–35 acres). Summer territories are smaller than winter territories. Along shorelines, the length of a home range varies from 250–2,000 meters (270–2,190 yards), with a width of 50–60 meters (55–66 yards).

CIRCADIAN RHYTHM

Crepuscular

MOVEMENT PATTERN

Non-Migrant

The European mink is carnivorous and has a diverse diet consisting largely of aquatic and riparian fauna. A study of stomach contents revealed a wide variety of foods, such as small mammals, including muskrats, voles, shrews, and moles; frogs and amphibians; fishes; insects; crayfish and crustaceans; and vegetation.

The European mink primarily preys on aquatic prey and hunts in both riparian zones and in the water. Voles, such as European water vole (Arvicola amphibius) and southern water vole (Arvicola sapidus) are the most important food source, closely followed by crustaceans, frogs and water insects. Fish are an important food source in floodlands, with cases being known of European minks catching fish weighing 1–1.2 kilograms (2.2–2.6 pounds).

The European mink’s daily food requirement is 140–180 grams (4.9–6.3 ounces). In times of food abundance, it caches its food.

Differences between the European mink’s diet and that of the American (Neovison vison) mink are small.

PREFERENCE

Generalist

STYLE

Forager

The European mink mating season occurs from February to March.

In the Moscow Zoo, estrus was observed on April 22nd to the 26th, with copulation lasting from 15 minutes to an hour.

Females are polyestrous and achieve sexual maturity at about one year.

During the mating season, the sexual organs of the female enlarge greatly and become pinkish-lilac in color, which is in contrast with the female American mink (Neovison vison), whose organs do not change.

Mink show the curious phenomenon of delayed implantation. Although the true gestation period is approximately 35-39 days, the embryo may stop developing for a variable period, so that as long as 76 days may elapse before the litter arrives. Between 45 and 52 days is normal.

There is only one litter per year, with births occurring in April and May. The number of young in a litter is between two and seven, but usually the litter is around four or five. Litters as large as 16 have been recorded at fur farms.

At birth, male European mink are approximately 7.39 centimeters (2.9 inches) in total length and 8.4 grams (0.3 ounces) and females are 7.19 centimeters (2.8 inches) and 7.6 grams (0.27 ounces). The kits average about 6.5 grams (0.23 ounces) and grow rapidly, tripling their weight 10 days after birth.

Young European mink are born blind, but are able to open their eyes after 30-31 days and the external auditory meatus open within 23 to 27 days.

By approximately four weeks of age, they have keen vision.

Teeth appear in the young within 15-17 days and are replaced by adult teeth by 60-72 days.

The lactation period lasts 2-2.5 months, though the kits are weaned at about 10 weeks and begin eating solid food after 20–25 days. They accompany the mother on hunting expeditions and begin tracking and capturing prey at the age of 56–70 days, and become independent and disperse at the age 70–84 days.

BREEDING SEASON

February-March

BREEDING INTERVAL

1 Year

ESTROUS

April

COPULATION

15-60 Minutes

PARENTAL INVESTMENT

Maternal

GESTATION

35-72 Days

BIRTHING SEASON

April-May

LITTER

2-7

BABY TEETH

15-17 Days

ADULT TEETH

60-72 Days

EARS OPEN

23-27 Days

EYES OPEN

30-31 Days

WEANING

10 Weeks

SOLID FOOD

20-25 Days

INDEPENDENCE

70-84 Days

SEXUAL MATURITY

1 Year

Predators of the European mink include the western polecat (Mustela putorius), the American mink (Neovison vison), the golden eagle (Aquila chrysaetos), large owls, and the red fox (Vulpes vulpes).

Red fox numbers have increased greatly in areas where the wolf and Eurasian lynx (Lynx lynx) have been extirpated, as well as areas where modern forestry is practiced. As red foxes are known to prey on mustelids, excessive fox predation on the European mink is a possible factor, though it is improbable to have been a factor in Finland, where fox numbers were low during the early 20th century.

The European mink was largely in the fur trade during the first half of the 20th century and was trapped for commercial purposes. The European mink was historically hunted extensively, particularly in Russia, where in some districts, the decline prompted a temporary ban on mink hunting to let the population recover. In the early 20th century, 40–60,000 European minks were caught annually in the Soviet Union, with a record of 75,000 individuals, an estimate which exceeds the modern global European mink population. In Finland, annual mink catches reached 3,000 specimens in the 1920s. In Romania, 10,000 minks were caught annually around 1960. However, this reason alone cannot account for the decline in areas where hunting was less intense, such as in Germany.

As of 2014, there is no data on present trade. Some recent illegal fur trade to neighboring countries from Romania has stopped because the fur-markets in these countries have crashed. The higher quality of farmed American mink (Neovison vison) fur makes it highly unlikely that trading could become an issue in European mink conservation, though the European mink is still caught in small numbers in Russia by trappers hunting for American mink.

WEARING APPAREL, ACCESSORIES Local

National

A 2001 study reported that there were approximately 25,000 European minks in Russia, and the world total was less than 30,000. There were also approximately 2,000 European mink found in France and approximately 1,000 in northern Spain. The current global population of European mink is unknown.

The European mink is in decline even in its currently remaining range enclaves. Only Romania can, perhaps, be regarded as an exception. In Romania, the presence of the European mink in the Danube Delta was confirmed relatively recently. The results of an IUCN mission in 2014 to Romania showed that the Danube delta population is clearly the most viable in the world. According to the assessment, the population in the delta might be around 1,000 – 1,500 individuals.

In the last ten years, a period exceeding three generations, this is inferred to have resulted in the loss of over half the population, and it is predicted to intensify in the next ten years to result in a decline rate exceeding 80%.

The western European mink populations of Spain and France have very low genetic variability. The southern population has slightly higher genetic variability, whilst the eastern populations have the greatest variability. Concerning the almost complete lack of genetic diversity observed in French and Spanish populations, speculations strongly indicate that very few individuals established the present-day western European populations, possibly following a human introduction. Misunderstandings have resulted in misconceptions of an alien origin of European mink in Spain and in France. However, the very low level of genetic diversity in western populations provides no scientific grounds to conclude that the European mink was introduced by humans to Spain and France, and no other line of evidence suggests this.

MATURE INDIVIDUALS

30,000

FRAGMENTATION

Severely Fragmented

Populations of European mink have been in decline for both ecological and commercial reasons. The primary reason for population declines is commercial trapping for fur. However, the mink also suffers as a result of habitat degradation/loss, water pollution, and hydroelectric constructions. The introduction of invasive species, notably American Mink (Neovison vison), has also negatively impacted European mink populations.

The decline of noble crayfish (Astacus astacus) has been proposed as a factor in the drop in European mink numbers, as minks are notably absent in the eastern side of the Urals, where crayfish are also absent. The decline in mink numbers has also been linked to the destruction of crayfish in Finland during the 1920s-1940s, when the crustaceans were infected with crayfish plague. The failure of the European mink to expand west to Scandinavia coincides with the gap in crayfish distribution.

AGRICULTURE & AQUACULTURE

Annual & Perennial Non-Timber Crops, Livestock Farming & Ranching

TRANSPORTATION & SERVICE CORRIDORS

Roads & Railroads, Shipping Lanes BIOLOGICAL RESOURCE USE Hunting & Trapping, Logging & Wood Harvesting

NATURAL SYSTEM MODIFICATIONS

Dams & Water Management/Use

INVASIVE & OTHER PROBLEMATIC SPECIES, GENES, & DISEASES

Invasive Non-Native/Alien Species/Diseases

POLLUTION

Domestic & Urban Waste Water, Industrial & Military Effluents, Agricultural & Forestry Effluents

rom 1981 to 1989, the European mink was introduced to southern Kurile Islands of Kunashir and Iturup, Russia, and Tajikistan, far away from the native distribution range. This introduction was unsuccessful; no stable populations were established in these islands.

In an attempt to save the European mink, British and Estonian biologists established a breeding population on an island in the Baltic Sea in 2000. The establishment of this island population in Estonia has resulted in a small breeding population of fewer than 100 individuals in Hiiumaa Island.