Callorhinus ursinus, commonly known as the Northern fur seal, is a species of marine mammal that belongs to the family Otariidae. Synonyms for this name include Arctocephalus ursinus, Otaria ursina, and Eumetopias ursina. These synonyms may cause confusion among researchers and laypeople alike, as they may refer to different species or genera of seals. Therefore, it is important to use the correct scientific name when referring to the Northern fur seal to avoid misinformation or misunderstandings. This marine mammal is primarily found in the North Pacific Ocean, where it spends most of its life hunting for fish and other marine creatures.