The north american river otter is a semi-aquatic and primarily nocturnal member of the weasel family. While they are known for their playful and almost comedic nature, as they are often seen sliding and rolling around, they are actually formidable hunters, preying mostly on fish, amphibians, mollusks and crustaceans. Otters once suffered a serious decline and were extirpated from much of their original range nationwide due to habitat loss, pollution and over trapping for the fur trade. Thanks to

Otter | Description, Habitat, Species, Distribution, Food, & Facts | Britannica