The mountain weasel is able to climb, run, and swim. Their long bodies and short legs allow them to be very agile. Mountain weasels are generally nocturnal, but may hunt during the day. Even though they live by themselves, they communicate with each other visually and sound. This animal has very good eye sight. They also communicate by sound to warn off predators, to protect their territories, and when mating. When scared, they make a loud chirring sound and excrete a very smelly odor.