Mustela Erminea

ERMINE
Mustela erminea


		Phylum: Chordata Class: Mammalia Order: Carnivora Family: Mustelidae Genus: Mustela Species: erminea

Description Geographic Range Natural History Status Additonal Resources Contact Information

Description

The ermine is a member of the weasel family. In North America, the ermine is commonly referred to as a short-tailed weasel and in Europe it is referred to as a stoat. Ermines typically have long, slender bodies with a long neck and short legs. They have bright black eyes and have slightly round ears. An adult ermine's total body length ranges from 9 to 11 inches with in additional length of the tail of 3 to 4 inches. The weight of an ermine ranges between 50 - 260 grams. The male is larger in size compared to the female. The coat of the ermine changes during the summer and winter seasons. During the summer, their short fine fur is a rich chocolate brown except for the underside of the body and legs which are a yellowish white color and the tip of the tail is black. As winter approaches, they shed their coat regrowing back completely white, however, still retaining the black tip of the tail.

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Geographic Range

Range
Northern Hemisphere: The ermine is found throughout all of Canada, Northern United States, Europe, and Asia. Their home range varies from 25 to 37 acres.

Habitat
Forest and Tundra: Ermines prefer woodlands, marshes, and open areas close to forests or shrub borders. They also live in tundras, especially in vegetated areas next to rocky cover. Tree roots, hollow logs, stone walls, and rodent burrows are used as dens. These dens are lined with dry vegetation and/or fur and feathers from prey.

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Natural History

Feeding Habits
Ermines are carnivorious and primarily hunt at night. They can eat up to 40% of its own body weight each day. They are highly skilled predators. By using their sense of smell to detect food, they kill their prey by accurately biting it at the back of the neck. The diet of these animals consists of small mammals, mainly rodents and rabbits, but they will also prey on birds, fish, and insects.

Lifestyle
Ermine are active during day and night. They are very curious animals; they are constanlty surveying their surroundings by raising their head and standing on their hind legs. They will investigate anything that cathces their attention including holes, tree trunks, and birds nests. They move more swiftly above and below ground due to their agile body composition.
Ermines are solitary and live in exclusive territories which they parolled and mark by scent. The only time individuals are seen together is during breeding season. The lifespan of an ermine is up to 7 years in the wild and 10 years in captivity.
Predators of this species include coyotes, badgers, foxes, owls, wolverines, and fur traders. Fur traders use the white pelt for trimming coats, stoles, and neckpieces. The black-tipped tails are used in United States as ornaments and in Europe they were used as tasals on royal robes.
Ermines are suspectible to a parasitic nematode, known as Skjabingylus nasicola, that infects their nasal passage, distorting the sinuses. Eventually, the skull is perforated and pressure is exerted on the brain, causing death. Shrews are thought to be a carrier host of the parasite.

Reproduction
Ermines are polygynous-promiscuous species. Their rerpoduction success is highly dependent on food availablity. They mate in late spring to early summer, producing only one litter, averaging 4 to 10 offspring, per year. After a gestation of 280 days, which includes an 8 to 9 month period of delayed development. Longer days begining in March trigger the resumption of fetal development. In April or May, the young are born altricial (helpless and blind). The young grow quickly and by the third week their eyes open. By the eighth week, the young are able to hunt with their mother. The females are able to mate within 60 to 70 days old, usually before they are weaned. Females also tend to remain at their birth place. While males do not begin mating until their second summer and disperse.