They wrestle and romp and slide down steep muddy slopes in summer and down icy riverbanks in winter. Otters use a variety of sounds to communicate among themselves. All species have a warning growl. In addition, otters use various kinds of chirps, chuckles, screams, and squeals to express their feelings to other otters. Most otters make their homes in burrows in riverbanks or under rocky ledges, or in abandoned dens of other animals.
Most female otters give birth to two or three young at a time.
The babies, called cubs or pups, are born blind. The young do not swim until they are several months old. People hunt otters for their valuable and beautiful fur. Certain species, especially the giant otter, are in danger of becoming extinct. Otters belong to the weasel family, Mustelidae.