Southern right whale dolphin
Southern Right Whale Dolphin is a common name for Lissodelphis peronii, a small and slender species of mammal found in cool waters of the southern hemisphere. The dolphin is one of two species of Right Whale Dolphin, Lissodelphis, the other being found in deep oceans of the northern hemisphere.
Southern Right Whale Dolphins are the only dolphins without dorsal fins in the southern hemisphere. They are smaller than Northern Right Whale Dolphins and have more white on their head and sides. They have slim, graceful bodies which are black on the upper side and white underneath. Their flippers are mainly white and are small and curved. Their flukes are small with a notch in the middle and concave trailing edges. Their beaks are small but distinct. They have between 43 and 49 teeth in each row of both jaws.
The distribution range of the species is subtropical to subantarctic oceans of the southern hemisphere. The range and total population have not been estimated or closely studied. Large populations are recorded off the western coasts of South America, where they are targeted by whaling operations; it is described as abundant in this region and off the coast of New Zealand. The range is associated with cold currents up the western and southern coasts of Africa, with a concentration recorded near Namibia.
The species is recorded with other cetaceans such as Lagenorhynchus obscurus, the dusky dolphin, and the pilot whale Globicephala macrorhynchus.
The southern right whale dolphin travels in groups of up to 1000 individuals, 52 being the average group size. The mass stranding of L. peronii on beaches, as many as 77, has been recorded.
The species was first published by Bernard Germain de Lacepede in 1804. The genus Lissodelphis, is placed within Delphinidae, the ocean dolphin family of cetaceans. The name of the genus was derived from Greek lisso , smooth, and delphis. The specific epithet peronii commemorates Francois Peron, who saw the species near Tasmania during an expedition. The common names for the species include Southern Right-whale dolphin and snake porpoise. Both species in the genus are also referred by the name "Right Whale Dolphin", a name derived from the Right Whales (Eubalaena) who also lack a dorsal fin.
This delphinid was not targeted by whaling operations of the nineteenth century, although it was sometimes caught for meat. The species is harvested by small fisheries in Peru, other threats include drowning and accidental capture in fishing operations elsewhere. Large numbers of L. peronii are sometimes taken by gillnetting and longline fishing in oceans off the southern coast off Australia.
The Patagonian toothfish is known to prey on Southern Right Whale Dolphin, and it is presumably eaten by sharks and Orcinus orca. L. peronii itself preys on an undetermined range of fish, but is known to eat crustaceans, squid and species of Myctophids. Their diet could possibly include euphausiids (krill). Little is known of their particular habits, and it is not known whether they search for their food near the surface or at greater depths.
Streamlined body, Short, defined beak, no teeth visible, Single blowhole, Black and white in colour, White underside, No fin, Fast active swimmer, May approach boats
Newborn calves are about 80 cm (32in) to 1 m in length. Adults are between 1.8 and 2.9 metres . Females tend to be slightly longer than males.
Adults weigh between 60 and 100 kg .
Fish, Squid, Octopus
Southern right whale dolphins are very graceful and often move by leaping out of the water continuously. When they swim slowly, they expose only a small area of the head and back when they surface to breathe. Breaching, belly-flopping, side-slapping and lob-tailing (slapping the flukes on the water surface) have been witnessed. They typically live in groups of between 2 and 100. Some groups are more nervous than others and will swim away from boats, whereas others will approach and possibly bow-ride. This tendency to bow-ride worked against them in the 19th century, as it allowed whalers to harpoon them from the bow and use them as food. Southern right whale dolphins are often seen in the company of hourglass dolphins.
Whale and Dolphin Conservation Society
This article is licensed under the GNU Free Documentation License. It uses material from the Wikipedia article Southern right whale dolphin