Dolphin This term has often been misused in the US, mainly in the fishing industry, where all small cetaceans (dolphins and porpoises) are considered porpoises, while the fish "dorado" is called dolphin fish. In common usage the term 'whale' is used only for the larger cetacean species, while the smaller ones with a beaked or longer nose are considered 'dolphins'. The name 'dolphin' is used casually as a synonym for bottlenose dolphin, the most common and familiar species of dolphin. There are six species of dolphins commonly thought of as whales, collectively known as blackfish: the killer whale, the melon-headed whale,
Fin whale for the Conservation of Cetaceans and Their Habitats in the Pacific Islands Region (Pacific Cetaceans MOU). Fin whale The fin whale ("Balaenoptera physalus"), also known as finback whale or common rorqual and formerly known as herring whale or razorback whale, is a marine mammal belonging to the parvorder of baleen whales. It is the second-largest species on Earth after the blue whale. The largest reportedly grow to long with a maximum confirmed length of , a maximum recorded weight of nearly , and a maximum estimated weight of around . American naturalist Roy Chapman Andrews called the fin whale "the