Sunday, April 10, 2011
April 10, 2011 : Great White Shark
Great White Shark
The great white shark, Carcharodon carcharias, also known as great white, white pointer, white shark, or white death, is a large lamniform shark found in coastal surface waters in all major oceans. The great white shark is very well known for its size, with the largest individuals known to have approached or exceeded 6 metres (20 ft) in length and 2,268 kilograms (5,000 lb) in weight. It reaches maturity at around 15 years of age and can have a life span of over 30 years. The great white shark is arguably the world's largest known extant macropredatory fish and is one of the primary predators of marine mammals. It is also known to prey upon a variety of other marine animals including fish, pinnipeds, and seabirds. It is the only known surviving species of its genus, Carcharodon.
The best selling novel Jaws and the subsequent blockbuster film by Steven Spielberg depicted the great white shark as a "ferocious man eater". In reality, humans are not the preferred prey of the great white shark. The IUCN treats the great white shark as vulnerable, while it is included in Appendix II of CITES.
Carolus Linnaeus gave the great white shark its first scientific name, Squalus carcharias in 1758. Sir Andrew Smith gave it the generic name Carcharodon in 1833, and in 1873 the generic name was identified with Linnaeus' specific name and the current scientific name Carcharodon carcharias was finalised.
Carcharodon comes from the Greek words karcharos, which means sharp or jagged, and odous, which means tooth.
Great white sharks live in almost all coastal and offshore waters which have water temperature between 12 and 24 °C (54 and 75 °F), with greater concentrations in the United States (Atlantic Northeast and California), South Africa, Japan, Australia (especially New South Wales and South Australia), New Zealand, Chile, and the Mediterranean. One of the densest known populations is found around Dyer Island, South Africa where much shark research is conducted.
It is an epipelagic fish, observed mostly in inland tributaries in the presence of rich game like fur seals, sea lions, cetaceans, other sharks, and large bony fish species. It is an open-ocean dweller and has been recorded at depths of around 1,220 m (4,000 ft). These findings challenge the traditional notion about the great white as being a coastal species.