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              Fish Facts  »  White Shark

              Description

              Body fusiform, snout conical and relatively short, long gill slits not encircling the head. Large first dorsal fin with the origin over pectoral fin inner margins. Second dorsal and anal fins minute. Caudal fin homocercal (crescent shaped), without a secondary keel below extension of caudal keel. Dorsal surface blue-grey to grey-brown, often bronzy. Ventral surface is white. Boundary between these tones is generally abrupt. Small, irregular dark spots may be present on the flanks posterior to the last gill slit. Most specimens exhibit a black oval blotch in the axil of the pectoral fin.

              Habitat

              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.

              Diet

              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.

              Fishery

              Despite its relative sparseness, the white shark's rate of capture by humans is alarmingly high. This is due in part to the increasing monetary value of its jaws and teeth. Entire specimens, some attaining more than 5m in length have been preserved by freezing or taxidermy for permanent public display or as private trophies or curios. Also, the flesh is utilized for human consumption, the skin for leather, the liver for oil, the carcass for fishmeal and the fins for shark-fin soup. Worldwide, specimens are reported annually from gill nets, trammels, herring weirs, purse seines, tuna enclosures as well as surface hooks, bottom longlines and set-lines.

              Size

              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 years.

              Range

              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.

              95998888九五至尊