Least Weasel (Mustela nivalis)

The Least Weasel weighs between 1 and 4 ounces with a body length of 4.5 to 10 inches. Its unique appearance includes a short tail with a constant black tip; it also gains a white winter coat. 

The weasel lives in various habitats across Europe, North America, and Asia, preferring areas with ample cover, such as marshes, woodlands, and grasslands. 

Despite its size, the Least Weasels are formidable creatures that feed on small rodents and can take down prey larger than itself. They are primarily active at night and are agile and quick.