The Dall’s Porpoise (Phocoenoides dalli) is the most active of the porpoise species, though this isn’t really saying much. It can often be found bowriding or “rooster-tailing” near boats and they frequently mistake for baby killer whales.
While sighting members of this species is often exciting, the origins of their scientific name are rather mundane. The generic name “Phocoena” (from both their Genus AND Family name – Phocoenoides and Phocoenidae respectively) is from the Greek “phokaina,” which means “porpoise.” So you might say it’s the porpoise-iest porpoise – even though, from a behavioural perspective, it’s not. Both the species name (dalli) and the common name both come from the same naturalist, Willian Healey Dall (1845-1927). Dall was an American naturalist who actually has 15 species named after him including our favourite porpoise, the Dall’s sheep, and numerous mollusks. Dall observed Dall’s porpoises in the wild and collected a sample in 1873 but it was another naturalist, Fredrick W. True, who officially described the species in 1885 and formally named the species after his friend Dall.
True doesn’t go without some name recognition though. Currently, there are two color morphs of Dall’s porpoise that are recognized as distinct subspecies, Dall’s porpoise (Phocoenoides dalli dalli) and True’s porpoise (Phocoenoides dalli truei) which is found only in the western Pacific Ocean and has a white belly patch that extends farther forward across the body than that of the dalli-type.