Kingdom: Animalia
Phylum: Chordata
Subphylum: Vertebrata
Class: Chondrichthyes
Order: Lamniformes
Family: Lamnidae
Genus: Carcharodon
Species: Carcharodon carcharias
The white shark is also commonly known as the great white shark. It is a solitary predator that can grow up to 6.6 meters (21 feet) in length.
Although this is the largest confirmed report of a white shark, indirect evidence suggests that there may be specimens off of southern Australia
which are 8 meters (26 feet) in length. The white shark is a robust, torpedo-shaped shark. The upper and lower lobes of the caudal fin are about
even in size, and its serrated triangular teeth are virtually symmetrical. Despite its name the white shark is only white on its underside; the
top of the shark is grey to black or blue.
Despite the world-wide attention given to the white shark through documentaries and articles, it remains one of the most poorly understood of
the world's sharks. Unfortunately, the general population believes the white shark to be a mindless, random killers - man-eaters - largely because
of movies like "Jaws" and other horror stories, and would feel safer if the species were eradicated. Exactly why sharks attack humans is unknown -
possibly raw aggression, territoriality, or misidentification (i.e. the sillhoette of a person lying on a surfboard strongly resembles that of a seal
or sea lion from below). What is known is that white sharks do not attack humans out of hunger; in other words, they do not attack people to eat them.
Most attacks, even those that prove fatal, do not result in any consumption of the victim - whole or in part. If death occurs, it is likely to be the
result of loss of blood, loss of tissue, or shock.
Size:
This shark is born at 1.1 m (3.6 feet), while adults reach at least 6.5 m (21.5 feet) and may attain 8 m (26.4 feet) in
length. Males are sexually mature at a total length in excess of 4.3 m (14 feet), while females are mature at lengths greater than 4.5 m (14.6 feet).
Distribution:
The white shark is widely distributed throughout temperate and subtropical regions of the world's oceans.
Habitat:
Occurs in coastal and offshore waters of continental shelves where the sea surface temperatures range between 12 and 24 degrees Celsius. It
occurs from surface waters to depths of 1280 m.
White sharks are most commonly seen in coastal areas, usually near rocky reefs, rarely near coral reefs. However the White Shark spends most of
it's life in open ocean or pelagic waters.
Reproduction:
This shark is oviphagous, with the developing embryos consuming eggs passed into the female oviducts. Full term embryos have
bulging yolk stomachs. Litter size was previously only thought to be about two young, but new evidence suggests as many as 9 to 11. Birth has
never been observed, but live birth is assumed.
Feeding:
Like many larger sharks, the diet of Carcharodon carcharias changes considerably as the shark grows larger. At smaller
sizes (3 m [10 feet]) white sharks feed heavily on elasmobranchs and bony fishes, especially bottom-dwelling forms. These smaller sharks have
teeth that are more slender, resembling those of mako sharks, and more finely serrated; this tooth shape is better for grasping than cutting.
Larger white sharks (>3 m [10 feet]) feed predominantly on seals, sea lions, sea otters and cetaceans. They are known predators of California
sea lions, New Zealand and Australian fur seals, elephant seals and harbor seals. There is one report of a large great white preying on a pygmy
sperm whale. Dolphins and porpoises are also important food in some regions (including the harbor porpoise and the bottlenose dolphin). The
teeth of the larger great white are more triangular, heavily serrated and thus are more effective for gouging hunks of flesh from large prey
or for cutting prey into smaller pieces. Adults also eat other sharks (in some areas this is an important food source), rays, bony fishes, and
invertebrates. In some areas, large white sharks depend on whale carcasses as a primary source of food.
Behavior:
This shark occurs singly, in pairs, or sometimes in aggregations (especially where food is abundant).
They display a high degree of
sexual segregation geographically, though this pattern fluctuates for unknown reasons; size segregation is also believed to be a characteristic
of white sharks. Seasonal distribution, occurring primarily in the nothern latitudes, is correlated with the seasonal availability of prey and
sea surface temperatures. Tagged individuals have demonstrated vertical movements through water temperatures from 17.8 degrees C and 5 degrees C
during its daily swimming activities.
Great white sharks often bear bite wounds or scars. When aggregating around a whale carcass white sharks will take turns feeding on the bloated
cetacean, with no more than two feeding on the whale at any one time (even when nine individuals were observed in the vicinity). Smaller individuals
will give way to larger sharks and on occasion larger, dominant individuals will chase and bite subordinates.
Distinguishing Characteristics:
This is a heavy bodied shark, with a conical snout and halfmoon (lunate) shaped tail. There is a keel on each side
of caudal peduncle. The teeth are large, serrated and triangular. The fill slits are relatively long. The great white shark is grayish above and
whitish below, with a sharp demarcation between the dorsal and ventral coloration. It often has a black spot at the pectoral fin axil and the underside
of the pectoral fins ate tipped with black.
