The mountain ermine, also known as a stoat, has a fascinating seasonal coat change. In winter, it develops a pure white coat, blending perfectly with snowy landscapes for camouflage and protection from predators. This coat, called “ermine,” sometimes retains a black-tipped tail. In summer, its fur changes to a reddish-brown on the back with a white underside, helping it blend into the warmer, snow-free environment. This adaptation ensures the ermine stays concealed and safe throughout the year.