Hourglass dolphin
| Hourglass dolphin | ||||||||||||
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jumping hourglass dolphins |
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| Systematics | ||||||||||||
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| Scientific name | ||||||||||||
| Lagenorhynchus cruciger | ||||||||||||
| ( Quoy & Gaimard , 1824) |
The hourglass dolphin ( Lagenorhynchus cruciger ) is a dolphin belonging to the genus of the short-snouted dolphins . He is a resident of the Southern Ocean and adjacent to the Southern Right Dolphin is the only so far south living dolphin.
features
The hourglass dolphin is 160 to 180 cm long and weighs between 90 and 120 kg. The muzzle is short and thick. The upper and lower jaw each have 56 to 60 teeth. The muzzle, forehead and back are black, as is a strip that begins at the eye with a white border and converges with the black of the back at the end of the base of the tail. It thickens under the fin, so that two large, elongated white spots appear on the flank, which are connected by a close connection to form an hourglass shape. The ventral side is white. The flippers are strongly curved, black on both sides and have pointed ends. The fin has a broad base and a more or less concave rear, in some, possibly older animals, the front edge of the fin is strongly curved and the end is hook-shaped. The base of the tail has noticeable keel-like ridges, especially on the underside. The fluke is black on both sides, with a distinct indentation in the middle and concave rear edges.
distribution
The distribution of the hourglass dolphin extends around the Antarctic pack ice , approximately between 65 ° and 45 ° south latitude . Most of the sightings took place in the open sea.
behavior
The hourglass dolphin gathers in groups of up to seven, rarely up to forty, the largest group sighted so far consisted of around 100 animals. They live in the same habitat as sei whales , pilot whales and minke whales and share their feeding areas with them. It feeds on fish and cephalopods .
Threat and protection
It is believed that the hourglass dolphin is quite common locally. Despite the infrequent sightings, it is estimated that 140,000 specimens of this species live today. It was never hunted or kept in captivity, and the number of animals killed as bycatch in fishing nets is very low. This makes the hourglass dolphin one of the few whales that is very little influenced by humans. It is listed in Appendix II of the Washington Convention on Endangered Species .
proof
- Mark Carwardine : Whales and Dolphins . Delius Klasing, Bielefeld 2008, ISBN 978-3-7688-2473-6 , p. 216-217 .
- Lagenorhynchus cruciger in the endangered Red List species the IUCN 2006. Posted by: Cetacean Specialist Group, 1996. Retrieved on 12 May, 2006.
