Little sperm whale
| Little sperm whale | ||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
Small sperm whale ( Kogia simus ) |
||||||||||||
| Systematics | ||||||||||||
|
||||||||||||
| Scientific name | ||||||||||||
| Kogia simus | ||||||||||||
| ( Owen , 1866) |
The small sperm whale ( Kogia simus ), also known as the small sperm whale , is a species of whale from the family of the dwarf sperm whale (Kogiidae). It is a relatively unknown species that is rarely seen in the sea. Most of the knowledge comes from research on stranded animals.
distribution
Small sperm whales are common in tropical and temperate oceans around the world. It lives closer to the coast than the pygmy sperm whale , and its preferred habitat is likely to be the region just outside the continental shelf . Stranding is documented from the Atlantic Ocean (in the west from the US state of Virginia to Brazil , in the east from Spain to the southern tip of Africa ), in the Indian Ocean from South Africa to Indonesia and on the Australian coast, in the Pacific Ocean from Japan and southern Canada south to in the central South Pacific.
In July 2010, a dead animal 2.6 meters long was washed up on the beach in Jebel Ali in the emirate of Dubai , which points to isolated occurrences in the Persian Gulf .
description
With a length of 2.1 to 2.7 meters and a weight of 136 to 272 kg, the small sperm whale is one of the smaller whale species. The skin is gray-blue on the upper side, the underside is lighter, almost whitish. The head is more like that of a porpoise than the giant head of a sperm whale . As with all sperm whales, only the lower jaw of the small sperm whale is fully dentate (14 to 26 teeth), while the teeth of the upper jaw are missing or stunted (0 to 6 teeth). It can be distinguished from the dwarf sperm whale by its larger fin and smaller body size. The flippers are short and wide. The blowhole on the left and the Spermaceti organ are also similar to the other species of sperm whale.
Way of life
Small sperm whales are characterized by their calm, inconspicuous swimming style. They show little air and little body surface and do not jump out of the water. They often lie motionless on the surface of the water and can therefore only be observed when the sea is calm. They live in schools of no more than ten animals. The diet of these whales is squid , fish and crustaceans , which they catch at depths of 500 to 1300 meters.
threat
Small sperm whales were actively hunted by whalers . They are still occasionally hunted today, particularly in Japan , Indonesia and the Caribbean . Because the small sperm whale lives closer to the coast than the pygmy sperm whale, it is more vulnerable to other threats such as being caught in fishing nets and marine pollution. However, there is neither an estimate of the total population nor information about the degree of risk. There is only an estimate for the Eastern Pacific, where researchers say 11,000 specimens live. To protect marine mammals such as the small sperm whale, a complete fishing ban has been imposed in the Tanon Straits , Philippines .
Systematics
Together with the dwarf sperm whale , the small sperm whale forms the genus of the dwarf sperm whale ( Kogia ), which together with the actual sperm whale are usually united in a common family of sperm whales , although some zoologists place them in their own family Kogiidae.
literature
- Ronald M. Nowak: Walker's Mammals of the World . Johns Hopkins University Press, 1999 ISBN 0-8018-5789-9
Web links
- Kogia sima inthe IUCN 2013 Red List of Threatened Species . Posted by: Taylor, BL, Baird, R., Barlow, J., Dawson, SM, Ford, JKB, Mead, JG, Notarbartolo di Sciara, G., Wade, P. & Pitman, RL, 2008 . December 2013.
Individual evidence
- ^ Group chances upon dead sperm whale in Dubai report on gulfnews.com from July 19, 2010; accessed on May 3, 2015