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Stoat

life science Maturity 9-11

The stoat is a small animal.

Mustela.erminea.jpg
Mustela.erminea.jpg
It lives in many places. It has a long body. In winter, it turns white. This helps it hide in snow. It is very fast. Do you like small animals?

51 words

The stoat is a small animal with a long body.

Mustela.erminea.jpg
Mustela.erminea.jpg
It lives in many lands. It has sandy-brown fur in the summer.
Mustela erminea in summer.jpg
Mustela erminea in summer.jpg
When it gets cold, the stoat changes. It grows a white coat to hide in the snow. The stoat keeps a black tip on its tail. This little animal is very fast and clever.

75 words

The stoat is a small animal with a long body.

Mustela.erminea.jpg
Mustela.erminea.jpg
It lives in many places in North America, Europe, and Asia. Some people call it an ermine.
Mustela erminea in summer.jpg
Mustela erminea in summer.jpg
This name comes from its white winter fur. In the past, people used this fur for fancy robes.

A stoat's coat changes with the seasons. In summer, its fur is sandy-brown on top. It is white on its belly. In the winter, the coat changes again. In cold northern areas, the fur turns completely white. This helps the stoat hide in the snow. It always keeps a black tip on its tail.

Stoats are very busy hunters. They have long bodies that help them move under snow. They can also hunt in small burrows. A male stoat is called a dog, hob, or jack. A female is called a jill. A group of them is called a gang or a pack.

Stoat and weasel.jpg
Stoat and weasel.jpg
They can also make a strong smell to defend themselves.

180 words

The stoat is a small, clever hunter found across much of the world.

Mustela.erminea.jpg
Mustela.erminea.jpg
It lives in many parts of Eurasia and northern North America. Some people call this animal an ermine. This name usually describes the stoat when it has a pure white winter coat. In the 15th century, Catholic monarchs used ermine fur for special capes. Members of the United Kingdom House of Lords also use it on ceremonial robes. Even images of the Infant Jesus of Prague show capes made of this fur.
Ermine fur петар први.jpg
Ermine fur петар први.jpg

A stoat's body is built for hunting in tricky places.

Stoat and weasel.jpg
Stoat and weasel.jpg
It has a very long, cylindrical body and a long neck. This shape helps it move easily through snow or inside small burrows. Its tail is quite long, always more than one-third of its body length.
Mustela erminea 02 MWNH 382e.jpg
Mustela erminea 02 MWNH 382e.jpg
The stoat also has large claws that it cannot pull back into its paws. To protect itself, the stoat can release a strong, musky smell from special glands. This scent is made of several sulphuric compounds.
Weasel (Mustela erminea).jpg
Weasel (Mustela erminea).jpg

Scientists have studied how these animals changed over a very long time.

Mustela.erminea.young.jpg
Mustela.erminea.young.jpg
About 5 to 7 million years ago, forests changed into open grasslands. This change led to many small, burrowing animals appearing. The ancestors of the stoat were actually larger than they are today. As they began eating these new small animals, the stoat grew smaller. During the Ice Age, their long bodies helped them thrive under the snow.
StoatDen3 (cropped).jpg
StoatDen3 (cropped).jpg

There are many different types of stoats living in different places.

Mustela erminea hibernica.jpg
Mustela erminea hibernica.jpg
A 2021 study split the group into three main species. One lives in Eurasia and Alaska, another is in most of North America, and one lives on islands near the Pacific Northwest. There are also 21 recognized subspecies. For example, the Tundra stoat is large and has a massive skull.
Mustela erminea in summer.jpg
Mustela erminea in summer.jpg
The Fergana stoat is much smaller and has a very light, soft coat.
035 Stoat in winter coat in Parc naturel régional Jura vaudois Photo by Giles Laurent.jpg
035 Stoat in winter coat in Parc naturel régional Jura vaudois Photo by Giles Laurent.jpg

Stoats have a very interesting way of changing their appearance.

Mustela Erminea head.jpg
Mustela Erminea head.jpg
They moult, or shed their fur, twice every year. In the spring, the change starts at the forehead and moves toward the belly. In the autumn, the change happens in the opposite direction. In cold northern areas, the fur turns completely white for the winter. This helps them hide, but they always keep a black tip on their tails.
Stoat and weasel.jpg
Stoat and weasel.jpg
This change is triggered by the amount of light the animal sees.

449 words

The stoat, known scientifically as Mustela erminea, is a small carnivore found across Eurasia and northern North America.

Mustela.erminea.jpg
Mustela.erminea.jpg
It is a member of the mustelid family, which includes weasels and otters. Because it lives in such a wide circumpolar range, the IUCN Red List classifies it as a species of Least Concern. One common name for the stoat is the ermine. This name specifically refers to the animal's pure white winter coat or the fur itself.

Throughout history, ermine fur has held significant cultural value. In the 15th century, Catholic monarchs used the fur for mozzetta capes. It has also appeared on ceremonial robes for members of the United Kingdom House of Lords. Even religious art, such as images of the Infant Jesus of Prague, features capes made of this fur.

Ermine fur петар први.jpg
Ermine fur петар први.jpg
While the fur is beautiful, the stoat can also be a problematic species. In the late 19th century, stoats were introduced to New Zealand to control rabbit populations. This backfired, as they had a devastating effect on native birds. Consequently, the species was named one of the world's top 100 "worst invaders."

The physical build of a stoat is specialized for its lifestyle.

Stoat and weasel.jpg
Stoat and weasel.jpg
It has an elongated neck and a cylindrical trunk that does not bulge at the abdomen. Its tail is relatively long, always exceeding one-third of its total body length.
Mustela erminea 02 MWNH 382e.jpg
Mustela erminea 02 MWNH 382e.jpg
The stoat possesses large, non-retractable claws on its five-toed feet. To defend itself, the stoat uses anal scent glands to release a strong, musky odor. This scent is produced by several sulphuric compounds.
Weasel (Mustela erminea).jpg
Weasel (Mustela erminea).jpg
This odor is chemically distinct from the secretions used by the similar-looking least weasel.

Stoats undergo a fascinating biological process called moulting to change their appearance.

Mustela Erminea head.jpg
Mustela Erminea head.jpg
They moult twice every year, a process triggered by the photoperiod, or the amount of light they receive. In the spring, the moult begins at the forehead and moves across the back toward the belly. In the autumn, the process moves in the reverse direction. In northern regions, the stoat develops a completely white winter coat, though it always retains a black tip on its tail.
035 Stoat in winter coat in Parc naturel régional Jura vaudois Photo by Giles Laurent.jpg
035 Stoat in winter coat in Parc naturel régional Jura vaudois Photo by Giles Laurent.jpg
In southern ranges, the coat remains brown but becomes denser.

Evolutionary studies show that the stoat's ancestors were once much larger. About 5 to 7 million years ago, northern forests were replaced by open grasslands. This environmental shift led to an explosion of small, burrowing rodents. The stoat's ancestors adapted to this new food source by reducing their body size.

Mustela.erminea.young.jpg
Mustela.erminea.young.jpg
During the Ice Age, their small size and long bodies allowed them to hunt effectively under the snow. The stoat and the North American long-tailed weasel were separated until 500,000 years ago. At that time, falling sea levels exposed the Bering land bridge, allowing for movement between regions.

Taxonomy, the science of naming and classifying living things, has recently changed for this animal.

Mustela erminea hibernica.jpg
Mustela erminea hibernica.jpg
A 2021 study split the original species into three distinct species. M. erminea sensu stricto lives in Eurasia and Alaska. M. richardsonii inhabits most of North America. M. haidarum is found on several islands off the Pacific Northwest coast.
Mustela erminea in summer.jpg
Mustela erminea in summer.jpg
There are also 21 recognized subspecies. For example, the Tundra stoat is large with a massive skull, while the Fergana stoat is very small with a light, soft coat.

There are notable physical differences between male and female stoats, a trait called sexual dimorphism. Males are roughly 25% larger than females and can weigh up to twice as much. On average, a male might measure 35 centimeters in length, while a female is smaller.

StoatDen3 (cropped).jpg
StoatDen3 (cropped).jpg
Even their skulls differ, with male skulls averaging 54 millimeters in length compared to 45 millimeters in females. These physical variations help scientists identify individual stoats and understand their population dynamics in the wild.

672 words
🖼️ Images & Media (15)
File:Mustela.erminea.jpg
Mustela.erminea.jpg
File:Mustelaerminaarcticaskull.png
Mustelaerminaarcticaskull.png
File:Mustela erminea hibernica.jpg
Mustela erminea hibernica.jpg
File:Mustela erminea in summer.jpg
Mustela erminea in summer.jpg
File:Mustela Erminea head.jpg
Mustela Erminea head.jpg
File:Stoat and weasel.jpg
Stoat and weasel.jpg
File:Mustela erminea 02 MWNH 382e.jpg
Mustela erminea 02 MWNH 382e.jpg
File:Weasel (Mustela erminea).jpg
Weasel (Mustela erminea).jpg
File:035 Stoat in winter coat in Parc naturel régional Jura vaudois Photo by Giles Laurent.jpg
035 Stoat in winter coat in Parc naturel...
File:Mustela.erminea.young.jpg
Mustela.erminea.young.jpg
File:StoatDen3 (cropped).jpg
StoatDen3 (cropped).jpg
File:Stoat killing a rabbit.jpg
Stoat killing a rabbit.jpg

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