The Japanese weasel's agility and lithe body allow it to pursue its prey anywhere; down tunnels, up trees, or into water. During winter, it spends its time pursuing rodents through snowy tunnels and, after catching and eating its target, it lays down to enjoy the warmth of its prey's burrow.

Endemic to Japan, the Japanese badger — like other badgers — lives in underground dens called "setts". However, the Japanese badger is known to be more solitary, with even mated pairs often living in separate setts. It is currently unknown why this is the case.