Taxonomy & Nomenclature
Physical Description / Field Identification
Southern right whale dolphins, along with their Northern Hemisphere counterparts, are the most slender of all cetaceans. The body shape is essentially the same as in the northern right whale dolphin, with a short, well-demarcated snout, small recurved flippers, extremely shallow (top to bottom) tail stock, small flukes with a concave trailing edge, and no hint of a dorsal fin or ridge.
The white coloration of the ventral area extends well up the sides, the sharp line demarcating black above and white below runs from the tail stock forward, dips down to the flipper insertion, and then sweeps back up to cross the melon between the blowhole and snout crease. The flippers are generally white, but the trailing edge has a black band. The flukes are white below, and dark gray, fading to white, on the leading edge.
The mouth is lined with 44-49 sharp, pointed teeth in each row. These dolphins reach lengths of at least 3 m and weights of 116 kg. Length at birth is probably about 1 m.
Can be Confused With
The unique body shape of this species should make it difficult to confuse with other species.
Distribution
Southern right whale dolphins are found only in cool temperate to subantarctic waters of the Southern Hemisphere. The southern limit appears generally to be bounded by the Antarctic Convergence. The range extends furthest north along the west coast of continents, due to the cold counterclockwise currents of the Southern Hemisphere. The northernmost record is at 12°S, in northern Peru. This is an open-ocean species, coming close to shore only in deep water coastal areas.
Ecology and Behavior
Large schools are characteristic of the southern right whale dolphin. Some estimates of group size range to over 1,000 animals. Associations with other marine mammal species are common, especially dusky dolphins and pilot whales. Like their northern cousins, dolphins of this species are active, energetic swimmers, often coming out of the water in clean low-angle leaps as they move at speed. Fluke slaps and other aerial displays are not uncommon. Southern right whale dolphins bowride occasionally.
Almost nothing is known of this species’ reproductive biology.
Feeding and Prey
A variety of fish and squid have been reported as prey; lanternfish (myctophids) are especially common.
Threats and Status
Southern right whale dolphins have been taken in recent years in Peru and Chile for crab bait and for human consumption. The only incidental catch of any magnitude that is known is in the swordfish gillnet fishery off Chile. Currently, they are listed as ‘Data Deficient’ (IUCN) and ‘Not Listed’ (ESA).
Links
References
Jefferson, T.A., M.W. Newcomer, S. Leatherwood and K. Van Waerebeek. 1994. Right whale dolphins Lissodelphis borealis (Peale, 1848) and Lissodelphis peronii (Lacepede, 1804). pp. 335-362 in S.H. Ridgway and R. Harrison, eds. Handbook of marine mammals, Volume 5: The first book of dolphins. Academic Press.
Lipsky, J.D. 2002. Right whale dolphins Lissodelphis borealis and L. peronii. pp. 1030-1033 in W.F. Perrin, B. Würsig and J.G.M. Thewissen, eds. Encyclopedia of marine mammals. Academic Press.
Newcomer, M.W., T.A. Jefferson and R.L. Brownell, Jr. 1996. Lissodelphis peronii. Mammalian Species 531:1-5.
Peddemors, V.M. 1999. Delphinids of southern Africa a review of their distribution, status and life history. Journal of Cetacean Research and Management 1:157-165.
Rose, B. and A.I.L. Payne. 1991. Occurrence and behavior of the southern right whale dolphin Lissodelphis peronii off Namibia. Marine Mammal Science 7:25-34.
Van Waerebeek, K., J. Canto, J. Gonzales, J. Oporto and J.L. Brito. 1991. Southern right whale dolphins, Lissodelphis peronii off the Pacific coast of South America. Zeitschrift fur Saugetierkunde 56:284-295.