Pelorus Jack (fl. 1888 – April 1912) was a Risso's dolphin that was famous for meeting and escorting ships through a stretch of water in Cook Strait, New Zealand, between 1888 and 1912. Pelorus Jack was usually spotted in Admiralty Bay between Cape Francis and Collinet Point, near French Pass, a notoriously dangerous channel used by ships travelling between Wellington and Nelson.
Pelorus Jack was shot at from a passing ship, and was later protected by a 1904 New Zealand law.
"Pelorus Jack" is also a popular Scottish Country dance, named in honour of the dolphin. This dance features a reel (or hay) where two people act as one but swap who leads at the reel ends, this is now known as a Dolphin Reel.
Pelorus Jack was approximately 13 feet (4 m) long and was of a white color with grey lines or shadings, and a round, white head. Although its sex was never determined, it was identified from photographs as a Risso's dolphin, Grampus griseus. This is an uncommon species in New Zealand waters, and only 12 Risso's dolphins have been reported in that area.