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The white shark, also known as
"great white", and "white pointer", is believed to have received its name from
the appearance of dead specimens lying on deck, ventral side up with stark white
underbelly revealed. The white shark is a macropredator,
known to be active during the daytime. Its most important prey items are marine
mammals (including, seals, sea lions, elephant seals, dolphins) and fishes
(including other sharks and rays). Marine reptiles are sporadically ingested,
mostly sea turtles. Marine birds and sea otters are almost exclusively rejected
as prey. These animals are commonly found having suffered injuries from
encounters with white sharks, but are rarely ingested.
| The white shark was
not always known as Carcharodon carcharias. Since 1758, when it was
named Squalus carcharias, this species has been afforded a variety of
scientific names, including Carcharias lamnia Rafinesque 1810,
Carcharias verus Cloquet 1817, Carcharodon smithii Bonaparte
1838, Carcharodon rondeletii Müller & Henle 1839, Carcharias
atwoodi Storer 1848, Carcharias maso Morris 1898, and
Carcharodon albimors Whitley 1939. The genus name Carcharodon is
derived from the Greek "karcharos" = sharpen and "odous" = teeth. The
species name carcharias, also translated from Greek, means point or
type of shark, leading to its common name in Australia of the white pointer.
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The white shark is cosmopolitan
but occurs mostly in temperate seas, with large individuals known to penetrate
tropical waters. It makes sporadic movements to cold, boreal waters and has been
recorded off Alaskan and Canadian coasts. It occurs in the western Atlantic from
Newfoundland to Florida, the northern Gulf of Mexico, the Bahamas and Cuba as
well from Brazil to Argentina and in the eastern Atlantic from France to South
Africa, including the Mediterranean. In the Indian Ocean, it occurs in the Red
Sea, off South Africa and the Seychelles Islands, as well as Reunion and
Mauritius. In the western Pacific, it ranges from Siberia to New Zealand and the
Marshall Islands, off the Hawaiian Islands in the central Pacific and from
Alaska to the Gulf of California and Panama to Chile in the eastern Pacific.
The white shark is principally
an epipelagic (living in the upper part of the water column) dweller of neritic
(nearshore) waters. However, it ranges from the surfline to well offshore and
from the surface and to depths over 250 m (775 ft). This shark commonly patrols
small coastal archipelagos inhabited by pinnipeds (seal, sea lions and
walruses), offshore reefs, banks and shoals and rocky headlands where deepwater
lies close to shore. The white shark usually cruises in a purposeful manner,
either just off the bottom or near the surface, but spends very little time at
midwater depths.
The maximum size attained by
white sharks has been the target of many debates and spurious information.
Scientists now suggest that the maximum total length of this species is about
680 cm (22.3 ft). Males mature at about 350 cm (10.5 ft) and females at about
450 cm (14 ft). White sharks are 120-150 cm (47-59 in) in length at birth.
Studies have indicated that white sharks live at least 14 years. However, in
reality, this number is likely much higher. Growth rates of the white shark are
also largely unclear, although one recent study included a tagged specimen that
had grown 69 cm (27 in) in a period of 2.6 yrs.
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