The southern right whale dolphin differs sufficiently from its northern counterpart to earn a classification as a distinct species within the genus. Although this animal is also long and slender, the white pigmentation that forms a thin elegant line along the ventral surface in the northern right whale dolphin becomes enlarged here, entirely covering the southern animal’s lower flanks. The southern animal’s forehead and beak are also white, and — an unusual feature among cetaceans — the dorsal surface of the flippers is often white as well.
Several sightings of these rare animals have confirmed that they swim in large herds.
Physical Description: Somewhat smaller than the northern right whale dolphin, with a stouter rostrum.
Color: Anterior flanks are black; the dorsal region is black from just past the demarcation of the rostrum to and including the flukes. Ventral regions are a well-developed gray to white from the rostrum past and including the flippers down into the lower peduncle region, ending at the beginning of the flukes. The underside of the flukes is white with a black border.
Fins and Flukes: No dorsal fin. Small, well-developed flippers are rounded toward the body and nearly pointed at their tips. The flukes are small, rounded at the tips, with a well-developed median notch.
Length and Weight: Southern right whale dolphins reach about 6 to 8 ft (1.8 to 2.4 m) and 150 lb (68 kg).
Teeth: 43 to 47 small, sharply pointed teeth are found in each side of the upper and lower jaws.
Feeding: Pelagic fish and squid.
Breathing and Diving: No information available.
Mating and Breeding: No information available.
Herding: Normally 2 to 50. Sightings around St. Paul’s Island confirm herds as large as 1,000. South American herds associate, but do not mingle with, Lagenorhynchus species in the same waters.
Distribution: This wholly pelagic species inhabits the temperate and subantarctic waters of the South Pacific Ocean, Tasman Sea, and waters directly south of Australia.
Migration: No information available.