American mink

American mink Temporal range: Recent PreꞒ Ꞓ O S D C P T J K Pg N ↓
Near Capisic Pond, Portland, Maine
Conservation status
Least Concern  (IUCN 3.1)[1]
Scientific classification
Domain:	Eukaryota
Kingdom:	Animalia
Phylum:	Chordata
Class:	Mammalia
Order:	Carnivora
Family:	Mustelidae
Genus:	Neogale
Species:	N. vison
Binomial name
Neogale vison (Schreber, 1777)[2]
Subspecies
15, see text N. v. vison N. v. aestuarina N. v. aniakensis N. v. energumenos N. v. evagor N. v. evergladensis N. v. ingens N. v. lacustris N. v. letifera N. v. lowii N. v. lutensis N. v. melampeplus N. v. mink N. v. nesolestes N. v. vulgivaga
American mink range in North America
Native (red) and introduced (pink) range of American mink
Synonyms
Mustela vison Vison vison Neovison vison

The American mink (Neogale vison) is a semiaquatic species of

Although superficially similar to the European mink, studies indicate the European mink's closest relative is the Siberian weasel (kolonok) of Asia. The American mink has been recorded to hybridize with European minks and polecats in captivity, though the hybrid embryos of the American and European minks are usually reabsorbed.^[7]

Subspecies

As of 2005^[update],^[8] 15 subspecies are recognised.

Subspecies	Trinomial authority	Description	Range	Synonyms
Eastern or little black mink N. v. vison ( Nominate subspecies )	Schreber, 1777	The smallest subspecies[9]	Eastern Canada, west to Hudson Bay; south in the interior to the Catskill Mountains, New York and to northern Pennsylvania	altaica (Ternovskii, 1958) borealis (Brass, 1911) nigrescens (Audubon and Bachman, 1854) tatarica (Popov, 1949) winingus (Baird, 1858)
California lowland mink N. v. aestuarina	Ginnell, 1916	Resembles N. v. energumenos, but smaller and has paler, less dense fur[9]	The lowlands of west-central Marin Counties
N. v. aniakensis	Burns, 1964
Western or Pacific mink N. v. energumenos	Bangs, 1896	A small and dark-coloured subspecies with dark sooty-brown fur. Males measure 24 inches (61 cm) in total length and 8.2 inches (21 cm) in tail length.[9]	Western North America, from Sierra Nevada Mountains in California and the Rocky Mountains in New Mexico
N. v. evagor	Hall, 1932
Everglades mink N. v. evergladensis	Hamilton, 1948		The southern tip of Florida
Alaskan mink N. v. ingens	Osgood, 1900	The largest subspecies, it resembles N. v. energumenos, but is lighter in colour. Males measure 28.8 inches (73 cm) in total length and 7.2 inches (18 cm) in tail length.[9]	Northern, western and central Alaska; the northern Yukon and the northwestern Mackenzie Mountains; south to the Alaska Peninsula and to Fort Good Hope
Hudson Bay mink N. v. lacustris	Preble, 1902	It has dark chocolate-brown fur above with white on the chin and irregularly distributed on the breast and between the hind legs. Males measure 27 inches (69 cm) in total length and 8 inches (20 cm) in tail length.[9]	The interior of Canada from Great Bear Lake and the western shores of Hudson Bay south through Alberta, Saskatchewan and Manitoba to southern North Dakota
Mississippi Valley mink N. v. letifera	Hollister, 1913	It has a light brown coat with white spots on the chin, throat and breast. Males measure 26 inches (66 cm) in total length and 9.4 inches (24 cm) in tail length.[9]	Northern Wisconsin and northern South Dakota south to northern Illinois, northern Missouri and southern Kansas
N. v. lowii	Anderson, 1945
Florida mink N. v. lutensis	Bangs, 1898	A medium-sized subspecies, it has a pale russet to clay- or reddish-brown coat. Males measure 23 inches (58 cm) in total length and 8 inches (20 cm) in tail length.[9]	The coasts of the southeastern United States from South Carolina to Florida
Kenai mink N. v. melampeplus	Elliot, 1904	Darker than energumenos, it has dark chocolate-coloured fur with slightly paler underparts and a white spot on the chin. Males measure 28 inches (71 cm) in total length and 7.2 inches (18 cm) in tail length.[9]	The Kenai Peninsula and Cook Inlet
Common mink N. v. mink	Peale and Palisot de Beauvois, 1796	A larger and more robust form than N. v. vison; it has similar colouration. Males measure 25.5 inches (65 cm) in total length and 8.5 inches (22 cm) in tail length.[9]	The Eastern United States, from the coast of New England south to North Carolina and in the interior to central Georgia and Alabama; westward through southern Pennsylvania and Ohio to Missouri and northeastern Texas	lutreocephala (Harlan, 1825) rufa (Hamilton-Smith, 1858)
Island mink N. v. nesolestes	Heller, 1909	Intermediate in size between N. v. ingens and N. v. energumenos, it has rather dark fur. The fur is Van Dyke brown, lighter on the cheeks and sides and darker on the tail. The underparts are walnut brown and white on the chin, with irregular white spots or areas on the throat, chest, inner legs and abdomen. Males measure 24.5 inches (62 cm) in total length and 7.3 inches (19 cm) in tail length.[9]	Admiralty Island in the Alexander Archipelago
Southern mink N. v. vulgivaga	Bangs, 1895	It resembles N. v. mink, but is paler and smaller, with rich and lustrous light brown fur which darkens at the end of the tail. Males measure 24.5 inches (62 cm) in total length and 7.5 inches (19 cm) in tail length.[9]	The coasts of Louisiana and Mississippi

Description

Build

The American mink differs from members of the genus

Domestic mink, which are bred in fur farms and are substandard genetically, have 19.6% smaller brains, 8.1% smaller hearts, and 28.2% smaller spleens than wild mink.[14]^[15] The feet are broad, with webbed digits.^[10] They generally have eight nipples, with one pair of inguinal teats and three pairs of abdominal teats.^[11] The adult male's penis is 2.2 in (5.6 cm) long, and is covered by a sheath. The baculum is well-developed, being triangular in cross section and curved at the tip.^[12]

Males measure 13–18 in (34–45 cm) in body length, while females measure 12–15 in (31–37.5 cm). The tail measures 6–10 inches (15.6–24.7 cm) in males and 6–8 in (14.8–21.5 cm) in females. Weights vary with sex and season, with males being heavier than females. In winter, males weigh 1–3 lb (500–1,580 g) and females 1–2 lb (400–780 g). Maximum heaviness occurs in autumn.^[5]

Fur

The American mink's winter fur is denser, longer, softer, and more close-fitting than that of the European mink. The winter fur's tone is generally very dark blackish-tawny to light-tawny. Colour is evenly distributed over all the body, with the under side being only slightly lighter than the back. The

On land, the American mink moves by a bounding gait, with speeds of up to 6.5 km/h (4.0 mph). It also climbs trees and swims well.[17] During swimming, the mink propels itself primarily through undulating movements of the trunk. When diving, it undergoes bradycardia, which is likely an adaptation to conserve oxygen.^[12] In warm water (24 °C (75 °F)), the American mink can swim for 3 hours without stopping, but in cold water it can die within 27 minutes.^[18] It generally dives to depths of 12 in (30 cm) for 10 seconds, though depths of 3 m lasting 60 seconds have been recorded. It typically catches fish after five- to 20-second chases.^[17]

Senses and scent glands

The American mink relies heavily on

American mink territories are held by individual animals with minimal intrasex overlap, but with extensive overlap between animals of the opposite sex. Most territories are in undisturbed, rocky coastal habitats with broad

The American mink normally only vocalises during close encounters with other minks or predators. The sounds it emits include piercing shrieks and hisses when threatened and muffled chuckling sounds when mating. Kits squeak repeatedly when separated from their mothers.[19] Ernest Thompson Seton reported hearing minks growl and snarl when confronting a threat.^[22] During aggressive interactions, mink assert their dominance by arching their backs, puffing up, lashing out their tails, and stomping and scraping the ground with their feet, while also opening their mouth in a threat-gape. Should this be unsuccessful, fights may result, with injuries to the head and neck.^[19]

Reproduction and development

The American mink is a promiscuous animal that does not form

The American mink is a carnivorous animal that feeds on

The American mink may pose a threat to poultry. According to Clinton Hart Merriam^[32] and Ernest Thompson Seton,^[33] although the American mink is a potential poultry thief, it is overall less damaging than the stoat. Unlike the stoat, which often engages in surplus killing, the mink usually limits itself to killing and eating one fowl during each attack. Studies in Britain indicate poultry and game birds only constitute 1% of the animals' overall diets;^[29] small mammals, especially rabbits, tend to dominate, followed by fish and birds, especially moorhens and coots.^[34]

Relationships with other predators

The American mink replaces and sometimes kills the European mink wherever their ranges overlap.

The species' natural range encompasses most of North America, from Alaska, through Canada and further into the United States except Arizona and the more arid areas of California, Nevada, Utah, New Mexico, and West Texas.^[1]

Introduced

Argentina

The American mink was deliberately introduced for commercial fur production in several provinces of Patagonia in 1930. The animals escaped or were released from farms in Chubut Province and now occur in the Chubut and Río Negro Provinces and Tierra del Fuego.^[43] In Argentina the mink is one of the major menaces of the Hooded Grebe, which risks becoming extinct.^[44]

South Chile

In

The first mink farm in Norway was built in 1927, with escapees establishing wild populations within 30 years of its establishment. The first feral mink populations arose in 1930, establishing territories in southwestern Norway. These feral minks, augmented by further escapees, formed the basis of a strong population in Hordaland by the end of World War II. Feral mink colonised eastern Norway in 1930 and had become established in most southeastern counties in the early 1940s. By 1950, feral mink reached central Norway, with further populations occurring in the northern counties of Nordland and Troms. During the post-World War II period until 1965, mink had colonised most of the country. In modern times, the American mink occupies all of the Norwegian mainland, but is absent on some islands.^[48]

The American mink was first imported to

In 1933, American minks were released into the

The species has been present in Iceland since the 1930s, and has become well established, despite it being heavily hunted since 1939. However, its population underwent a 42% decline during the years 2002–2006, which coincided with a decline in sand eel populations resulting in a drop in the seabird populations on which the minks feed.^[51]

Diseases and parasites

The American mink often carries light

Transmissible mink encephalopathy (TME) is a prion disease of mink, similar to BSE in cattle and scrapie in sheep. A 1985 outbreak of TME in Stetsonville, Wisconsin resulted in a 60% mortality rate for the minks.^[53] Further testing revealed this agent is transmissible between mink, cattle, and sheep. The Stetsonville outbreak may have been due to the mink being fed carcasses or otherwise consuming other infected animals.^[54]

Toxoplasma gondii has been recorded in American minks in southern Chile, with 59% seroprevalence in the 73 mink analyzed in one study. Southern river otters of the area were also found to have high T. gondii seroprevalence in this study, showing a high exposure of semiaquatic mustelids to the parasite in this part of Chile.^[55]

Decline of wild mink

Because of numerous incidents of domestic mink escaping from fur farms and establishing themselves in the wild, concern has arisen among conservationists of the possible repercussions such escapes may have on natural wild mink populations. Domestic mink are larger than wild mink, which may cause problems with the ecosystem when they escape. Minks are solitary, territorial animals and are intolerant of other minks. In times of overpopulation, they control their own numbers by either killing each other through direct conflict or by causing weaker minks to be driven from territory until starvation sets in.^[56] When hundreds or thousands of released domestic minks flood an ecosystem, it causes a great disturbance for the wild minks, resulting in the deaths of the majority of the released mink and many of the wild ones from starvation or injuries incurred while fighting over territory.^[56] When a domestic mink survives long enough to reproduce, it may cause problems for the wild mink populations.^[57] The adding of weaker domestic mink genes into wild mink populations is believed by some to have contributed to the decline of mink populations in Canada.^[57]

A 2006 study in Denmark concluded, due to frequent escapes from existing mink farms, "Closing mink farms may result in a crash of the free-ranging population, or alternatively it may result in the establishment of a better-adapted, truly feral population that may ultimately outnumber the population that was present before farm closures." The study reported more information would be necessary to determine the outcome.^[58] Another Danish study reported a significant majority of the "wild" mink were mink which had escaped from fur farms. About 47% had escaped within two months, 31% had escaped prior to two months, and 21% "may or may not have been born in nature." The survival rate for recently released minks is reportedly lower than for wild minks, but if feral minks survive at least two months, their survival rate is the same as for wild minks. The authors suggest this is due to the rapid behavioural adaptation of the animals.^[59]

Relationships with humans

Disease

The American mink and European mink^[60] have both been found to transmit SARS-CoV-2, the virus that causes COVID-19.

Fur use

American minks are primarily used in manufacturing

Although difficult to catch, the American mink, prior to being commercially farmed, was among the most frequently trapped furbearers as, unlike other furbearing mammals, it did not hibernate in winter, and could thus be caught on a nightly basis even in the far north.^[63] Minks were legally trapped from early November to early April, when their pelts were prime.^[64] Minks caught in traps cling to life with great tenacity, having been known to break their teeth in trying to extricate themselves from steel traps.^[65] Elliott Coues described a trapped mink thusly:

One who has not taken a Mink in a steel trap can scarcely form an idea of the terrible expression the animal's face assumes as the captor approaches. It has always struck me as the most nearly diabolical of anything in animal physiognomy. A sullen stare from the crouched, motionless form gives way to a new look of surprise and fear, accompanied with the most violent contortions of the body, with renewed champing of the iron till breathless, with heaving flanks, and open mouth dribbling saliva, the animal settles again, and watches with a look of concentrated hatred, mingled with impotent rage and frightful despair. The countenance of the Mink, its broad, low head, short ears, small eyes, piggish snout, and formidable teeth, is always expressive of the lower and more brutal passions, all of which are intensified at such times. As may well be supposed, the creature must not be incautiously dealt with when in such a frame of mind.^[65]

One Native American method involved using a bait (usually a slit open chicken carcass filled with fish oil and oysters) tied to a rope and dragged around an area laden with traps. A mink would thus follow the trail into one of the traps. Another indigenous method involved placing traps scented with muskrat and female mink musk on top of disused muskrat dens by water bodies. Attracted by the scent of food and a female, the mink would get caught in the trap and drown.^[66] On the American prairies, only the steel trap was used, due to the lack of timber.^[67]

Farming

Breeding American minks for their fur began in the late 19th century, as increasing enthusiasm for mink pelts made the harvesting of wild minks insufficient to meet the new demands. American minks are easily kept in captivity, and breed readily.^[68] In 2005, the U.S. ranked fourth in production behind Denmark, China and the Netherlands. Minks typically breed in March, and give birth to their litters in May. Farmers vaccinate the young kits for botulism, distemper, enteritis, and, if needed, pneumonia. They are harvested in late November and December. Methods for killing animals on fur farms, as on all farms, are detailed in the American Veterinary Medical Association's Report on Euthanasia which is used as a voluntary guideline for state departments of agriculture which have jurisdiction over all farms raising domesticated livestock, including minks.^[69] In the past, some mink farms successfully provided pools of water for the mink to swim;^[70] however, this practice is unheard-of in modern mink production. Minks are motivated to access swimming water, and the absence of water is a source of frustration on modern farms.^[71] The ideal diet for farm-bred minks consists of four to five ounces of horse meat and a quarter-pint of milk once daily.^[70]

Colour mutations

Selective breeding has produced a number of different colour shades in mink peltries, ranging from pure white, through beiges, browns, and greys, to a brown that is almost black. The two standard strains are brown and "black cross" which, when paired, produce numerous colour variations. When an albino mink is born, it is standard procedure in fur farms to breed it to other colour mutations to produce grey and light-brown pastel shades. The following graph is a simplification of the main colour strains:^[72]

Colour variant	Image	Description
Pastel		Pale brown and beige fur with darker guard hairs of various hues[72]
Royal pastel		Same as above, but with a bluish cast[72]
Silverblu		Bluish grey fur fibre and guard hairs which are sometimes white-tipped, giving a silvery blue tone, pelts of this type with a brownish cast are less valuable.[72]
Breath of spring		Also known as "platinum", this variety has a brighter bluish cast than the Silverblu type.[72]
Blufrost		Pale brown fur fibre interspersed with dark brown guard hair, sprinkled with white guard hairs[72]
Kohinur		Also known as "black cross", this variety has white or cream-coloured fur fibre with a sprinkling of blackish guard hairs throughout the body, with the greatest concentrations being on the back and shoulders.[72]
Cerulean		Also known as "sapphire", this variety has bluish-grey fur fibre with mauve, blue-grey guard hair, with the greatest depth of colour being on the back.
Steel blue		Dull battleship grey guard hair, with lighter shaded fur fibre[72]
Lutetia		Also known as "Aleutian", this variety has gun-metal grey fur fibre and guard hair.

As pets

Wild mink can be tamed if caught young, but can be difficult to handle and are usually not handled bare-handed.^[73] In the late 19th century, tame American minks were often reared for ratting, much as ferrets were used in Europe. Some modern ratters have revived this practice using farm-raised mink, sometimes alongside ratting dogs.^[74] They are sometimes more effective ratters than terriers, as they can enter rat holes and drive rats from their hiding places.

When mink of wild stock are confined with tame ones, the wild invariably dominate the tamed mink. They have also been known to dominate cats in confrontations.^[75] Although intelligent, minks are not quick to learn tricks taught to them by their owners.^[76] Because of their fondness for bathing, captive American minks may enter kettles or other open water-containing vessels.

Although domestic minks have been bred in captivity for almost a century, they have not been bred to be tame. Domestic minks have been bred for size, fur quality, and color. However, the U.S. Fur Commission claims "mink are truly domesticated animals", based on the number of years they have been kept on fur farms.^[77]

Literature

As an

See also

• Aleutian disease
• European mink
• Sea mink
• Fur farming

References

Sources

• Anthony, Harold Elmer (1928). "Field Book of North American Mammals".
  hdl:2027/mdp.39015020808831
  . Descriptions of every mammal known north of the Rio Grande, together with brief accounts of habits, geographical ranges, etc.

• Bachrach, Max (1953). Fur: A practical treatise (3rd ed.). New York, NY: Prentice-Hall.

• Coues, Elliott (1877). Fur-Bearing Animals: A monograph of North American mustelidae (Report). Washington, DC: Government Printing Office.

• Feldhamer, George A.; Thompson, Bruce Carlyle; Chapman, Joseph A. (2003). Wild Mammals of North America: Biology, management, and conservation. JHU Press.
  ISBN 978-0-8018-7416-1
  .

• Gates, William Gilford (1915). The Propagation of Mink and Marten. Spokane, Shaw, & Borden Co.

• Harding, Arthur Robert (1906). Mink Trapping. Columbus, OH: A.R. Harding (self published). A book of instruction giving many methods of trapping

• Merriam, C. Hart (1886). The Mammals of the Adirondack Region, Northeastern New York. New York, NY: Holt. With an introductory chapter treating of the location and boundaries of the region, its geological history, topography, climate, general features, botany and faunal position

• Harris, Stephen; Yalden, Derek (2008). Mammals of the British Isles (4th, revised ed.). Mammal Society.
  ISBN 978-0-906282-65-6
  .

• Heptner, V.G.; Sludskii, A.A. (2002). Mammals of the Soviet Union. Vol. II, part 1b, Carnivores (Mustelidae and Procyonidae). Washington, DC:
  ISBN 978-90-04-08876-4
  .

• Kurtén, Björn (1980). Pleistocene Mammals of North America. New York, NY: Columbia University Press.
  ISBN 978-0-231-03733-4
  .

• Seton, Ernest Thompson (1909). Life-Histories of Northern Animals: An account of the mammals of Manitoba. New York, NY: Scribner.

• Stone, Witmer; Cram, William Everett (1902). "American animals".
  hdl:2027/mdp.39015020808831
  .

External links

Wikispecies has information related to Neovison vison.

Wikimedia Commons has media related to Neovison vison.

Look up American mink in Wiktionary, the free dictionary.

• Bonesia, Laura; Palazon, Santiago (2007). The American mink in Europe: Status, impacts, and control. Biological Conservation (Report). Vol. 134. p. 470 – via academia.edu.

• Neovison vison (Report). North American Mammals. Washington, DC: Smithsonian Institution.

• "Mink Research Library" (main). Archived from the original on 2013-05-13.

• Mink Control Project (Report). Scottish Invasive Species Initiative.