What's the Difference Between a Stoat and a Weasel?

Upon first seeing a stoat, many people assume this small carnivorous mammal is related to a weasel. And that's a really good guess, especially since they are both small, brown, fast and ferocious mustelids, with sinuous bodies and short legs.

Although stoats are weasel-like animals, "they are generally much bigger in size with a distinguishing black tail tip," says Charli Burbidge, co-founder of the U.K.-based website Petz, via email. "Their appearance is similar to the weasel," she adds, "but a stoat has an elongated neck and longer skull. Stoats also have round, black protruding eyes, with short flat ears and huge claws compared to the size of their digits."

Another thing that sets weasels and stoats apart: Stoats have an unexpected superpower! They are agile hunters, typically attacking prey like rats, mice, possums, birds and squirrels by a single bite to the neck. But when it comes to hunting rabbits, stoats use their clever mind to hypnotize the creatures before hunting them down. The stoat on the hunt will go nuts — spinning, jumping and twisting — with its manic behavior attracting the rabbit's attention. As the stoat moves closer and closer, the rabbit remains transfixed until, well, it's too late.

Eager to find out more about these cool little creatures? Here are five more fun facts you might not know about the stoat, which is typically found along the English countryside.

1. They Change Color in Winter

The stoat's summer coat is reddish-brown with a creamy tummy, but in the winter it turns all white. "This is to help them stay less noticeable," Burbridge says. "However, their black tip tail remains throughout the seasons."The winter coat is thicker than its summer one to help keep the stoat warm, and the white fur camouflages the animal in the snow.

When in its winter coat, the stoat also is known as an ermine. In moderately cold climates, the fur becomes only partly white. Unfortunately, the stoat's winter coat is especially prized by the fur trade, and used to trim coats and stoles.

2. They Don't Make Great Pets

Technically you can have a stoat as a pet, if you like to live on the edge. While they are extremely adorable, stoats definitely are not meant to share a home with a cat, dog, small pet or child. Stoats cling to the backs of their preys' necks, and victims usually are unable to fight back with their paws, claws or wings. Eventually, the neck wound widens until the blood flow is unstoppable. Yikes!

Cats have a greater chance of survival than dogs against stoat attacks. Mustelids can't climb, and cats often can reach the back of their necks with their claws — something dogs don't find as easy. Furthermore, if you do find stoats up for sale, they usually are illegally captured wild specimens, so if you buy one, you'll be promoting illegal and harmful wildlife trade.

3. The Stoat Is an Invasive Species

In fact, it was nominated as one of the 100 World's Worst Invasive Alien Species by the International Union for Conservation of Nature in 2000. The list, which is largely dominated by plants and insects, includes the cute little stoat as one of the top 10 invasive mammals.

What makes them so invasive? Stoats are native to Asia, Europe and North America, but they were introduced to New Zealand and Britain (against the advice of many scientists) to help control the rabbit population. (Remember how they can reportedly immobilize rabbits by mesmerizing them with a "dance"?) However, after just a few years, the bird population rapidly declined, and their introduction also had a devastating effect on rodent species.

That's because stoats can adapt to many environments and thrive in most climates. The stoat also is an opportunistic predator, moving rapidly and checking every available burrow or crevice for food, and often climbing trees to find bird nests.

4. A Stoat Pregnancy Lasts Around 300 Days

When they finally do give birth, they typically have between five and 15 babies (called kits) at a time. They also usually only have one litter during their life, which is an average of four to six years. The males don't help raise the babies.

"When the young are born, they are born blind and toothless," says Burbridge. "They are also born covered in white-pink fur, and they will start to gain their sight around 4 weeks of age. This white-pink fur will change as the stoat gets older."

5. They Steal the Dens of Their Prey

Male and female stoats live separately in their own dens, and stoats are known to have several dens they use at the same time. Their den sites are well-hidden, typically the nests of prey they've killed and taken over. They include holes in tree trunks and rabbit burrows. Stoats check every burrow and hollow they see, and if they find a ground-nesting bird it has very little chance to escape.