Fraser's Dolphin

Fraser's dolphin, or the Sarawak dolphin, is a stocky oceanic dolphin of deep waters, found mainly in the Pacific and to a lesser extent in the Indian and Atlantic Oceans. The back is grey-blue to grey-brown, with a dirty cream line along the flank from the beak, above the eye, to the anus and a dark stripe below it. The belly and throat are usually white, sometimes tinged pink, and the lack of a prominent beak is distinctive. It can be confused with the striped dolphin (Wikipedia, general species account).

Adults are about 2.75 m long and 200 kg. It swims quickly in large, tightly packed groups of 100 to 1,000, often porpoising, and groups fleeing a fishing vessel have been described as very dramatic. It feeds on pelagic fish, squid and shrimp found 200–500 m down, where almost no sunlight reaches, and so uses echolocation alone. Its occurrence in Japanese waters is documented by the National Museum of Nature and Science marine-mammal database.