Commerson's Dolphin
| Scientific Name | Cephalorhynchus commersonii |  | |
| English Common Name | Commerson’s Dolphin | ||
| Taxonomy | Class: Mammalia Order: Cetacea Sub-order: Odontoceti Family: Delphinidae Genus: cephalorynchus Species: commersonii | ||
| Behaviour | Likely to approach boats and known to bow-ride. Very active both on the surface; breaching often and underneath it and its erratic swimming pattern makes it hard to know where it will next surface. | ||
| World Distribution | Commerson’s dolphins are only found in a few places around the world. They are found off the east coast of Argentina (including around the Falkland Islands), off the very southern coast of Chile, and around the Kerguelen Island in the Indian Ocean. Most sightings are close to shore in waters less than 100m deep. Seems to prefer areas with a large tidal range, often near kelp beds. | ||
| Morphology | Commerson’s dolphins are very striking in their appearance & are quite easy to identify. Their bodies are small and similar in shape to a porpoise rather than a dolphin, but they certainly behave like dolphins. At birth, they are grey, black and brown, but as they get older their colouring changes. When they are mature, they are mainly white with black heads, flukes, fins and flippers. There is always a white patch under the chin and a black patch on the belly. It is possible to tell males from females by the shape of the black patch on the belly. It is shaped like a raindrop in males and like a horseshoe in females. The population around the Kerguelan Islands in the Indian Ocean are thought to be geographically isolated from the South American populations and may form a separate sub-species. Most individuals are larger than the South American animals and are black, grey and white in colour. Newborn Commerson’s dolphin can be as short as 55 cm and weigh approximately 6 kg. Adults are usually between 1.3 and 1.7m in length and weigh between 35 and 60 kg. Commerson’s dolphins diet includes crustaceans, such as shrimps and crabs, fish, squid and octopus, and other invertebrates such as starfish. | ||
| Threats | The primary threat is incidental entanglement in gill-nets and other fishing gear. As with the Black (or Chilean) and Dusky dolphins, there is also an illegal hunt for Commerson’s dolphins for use as bait in the Chilean king crab fishery. | ||
| Status | No abundance estimate is available for this species. | ||
| Conservation Activities | CMS: Appendix II | ||
