Blue-gray blind shark
Blue-gray blind shark | ||||||||||||
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Blue-gray blind shark ( Brachaelurus colcloughi ) |
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Systematics | ||||||||||||
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Scientific name | ||||||||||||
Brachaelurus colcloughi | ||||||||||||
Ogilby , 1908 |
The blue-gray blind shark ( Brachaelurus colcloughi , syn .: Heteroscyllium colcloughi ) is a shark from the Brachaeluridae family, to which only the blind shark ( Brachaelurus waddi ) belongs. It occurs on the south and east Australian coast from Queensland to New South Wales and reaches a body length of about 75 centimeters. To date, the shark is known in only 20 individuals and is accordingly classified as endangered.
Appearance and characteristics
The blue-gray blind shark reaches an average body length of 50 to 65 cm and a maximum body length of around 75 cm. It has a gray to blue-gray back coloration, the belly side is white to yellowish in color. In the young animals there are black markings on the dorsal and caudal fins, which fade in adulthood. The head has large nasal pits and the suction hole is also quite large, with distinct barbels in front of the comparatively small mouth.
The shark has a short, compressed body. It has an anal fin and two dorsal fins that start very far back on the back. The first dorsal fin is slightly larger and begins roughly above the base of the pelvic fins, the second well in front of the anal fin base. As with other nurse sharks, the caudal fin consists of a strong caudal stalk and a surrounding caudal border, with only a very small gap between the anal fin and the lower caudal fin.
Way of life
The blue-gray blind shark is a predominantly nocturnal species in the area of the continental shelf, where it lives near the sea floor in very shallow places up to 6 meters deep. Little information is available about his behavior and way of life.
It is viviparous, with the female likely giving birth to six to eight juvenile sharks. The animals probably reach sexual maturity at a length of about 50 cm.
distribution
The blue-gray blind shark is found on the south and east Australian coast from Queensland to New South Wales . The preferred habitat make rocky seabed areas in the Tidenzone is (partly it is also used in rock pools before), he also lives in seagrass areas.
Existence and endangerment
The blue-gray blind shark is listed as endangered ("vulnerable") in the IUCN Red List . Scientifically only about 20 individuals are currently known, all of which were caught in very heavily fished coastal areas; the total population is therefore not known and is estimated to be very low.
Individual evidence
- ↑ Brachaelurus colcloughi in the endangered Red List species the IUCN 2009. Posted by: Compagno, Hunting Association, load, P. & Stevens, J., 2000. Retrieved on 29 May, 2009.
literature
- Leonard Compagno , Marc Dando, Sarah Fowler: Sharks of the World . Princeton University Press , Princeton and Oxford 2005, ISBN 978-0-691-12072-0 , p. 160.