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Detailed Great White Shark (Carcharodon Carcharias) information, including species classification and further information through external links.
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Great White Shark
The great white shark is a streamlined swimmer and a ferocious predator with 3,000 teeth at any one time. This much-feared fish has a torpedo-shaped body, a pointed snout, a crescent-shaped tail, five gill slits, no fin spines, an anal fin, and three main fins: the dorsal fin (on its back) and two pectoral fins (on its sides). When the shark is near the surface, the dorsal fin and part of the tail are visible above the water.
Only the underbelly of the great white shark is actually white; its top surface is grey to blue grey. This is useful in hunting its prey. The great white usually strikes from below and its greyish top coloration blends in with the dark water, enabling it to approach the prey unobserved.
Great whites average 12 to 16 feet long (3.7-4.9 m) long. The biggest great white shark on record was 23 feet (seven m) long, weighing about 7,000 pounds (3200 kg). Females are larger than males, as with most sharks. Shark pups can be over five feet (1.5 m) long at birth.
Young great white sharks eat fish, rays, and other sharks. Adults eat larger prey, including pinnipeds (sea lions and seals), small toothed whales (like belugas), otters, and sea turtles. They also eat carrion (dead animals that they have found floating dead in the water).
Great whites do not chew their food. Their teeth rip prey into mouth-sized pieces, which are swallowed whole.
A big meal can satisfy a great white for up to two months.
The great white shark has 3,000 teeth at any one time. They are triangular, serrated (saw-edged), razor-sharp, and up to three inches (7.5 cm) long.
The teeth are located in rows, which rotate into use as needed. The first two rows are used in obtaining prey; the other rows rotate into place, as they are needed. As teeth are lost, broken, or worn down, they are replaced by new teeth that rotate into place.
Sharks primarily use their sense of smell followed by their sensing of electric charges. The shark's other senses, like sensing changes in water pressure, eyesight, and hearing, are less important.
The great white's nostrils can smell one drop of blood in 25 gallons (100 litres) of water. (Shark nostrils are only used for smell and not for breathing, like our nostrils. They breathe using gills, not nostrils.)
The sensing of minute electrical discharges in the water is accomplished by a series of jelly-filled canals in the head called the ampullae of Lorenzini. This allows the shark to sense the tiny electrical fields generated by all animals, for example, from muscle contractions. It may also serve to detect magnetic fields which some sharks may use in navigation.
The great white is the only type of shark that will go to the surface and poke its head up out of the water. No one knows exactly why it does this; perhaps it is to see potential prey such as surface-dwelling sea lions.
Most great white attacks are not fatal. Great whites account for about half to a third of all 100 annual reported shark attacks. Of these 30 to 50 great white attacks, only 10-15 people die.
Great whites are usually solitary animals but are occasionally spotted travelling in pairs.
Great white sharks are found near shores along most of the temperate (not very hot and not very cold) coastlines around the world.
Great white sharks have been observed along the coastlines of California to Alaska, the east coast of the USA and most of the Gulf coast, Hawaii, most of South America, South Africa, Australia (except the north coast), New Zealand, the Mediterranean Sea, West Africa to Scandinavia, Japan, and the eastern coastline of China and southern Russia.
In the fall, some females migrate to warmer waters (for example, southern California) to give birth.
Great whites are propelled through the water by their powerful tails. The fins are only used for balance. Their movement is more like an aircraft's flight than other fishes swimming. They average about two mph (3.2 kph) but can swim 15 miles per hour (24 kph) in short bursts.
They swim constantly or they will sink since, like other sharks, they have no gas filled swim bladder to keep them afloat like bony fish do. Like other sharks, their large, oily liver provides some buoyancy (floating ability). but they are still heavier than water and will sink unless they are propelling themselves through the water. Also like other sharks, they cannot swim backwards or even come to an abrupt stop, because their fins are not flexible like other fish. In order to go backwards, they must stop swimming and fall backwards, using gravity to propel themselves backwards.
Great white sharks reproduce via aplacental viviparity; they give birth to 2-14 fully formed pups that are up to five feet (1.5 m) long. Like all sharks, fertilization of the eggs occurs within the female. The eggs hatch within the female and are nourished by eating unfertilised eggs and smaller siblings in the womb. There is no placenta to nourish the babies - they must fend for themselves, even before birth. They swim away from the mother immediately after birth; there is no maternal care giving.
No one knows the life span of the great white shark. Some people estimate it to be about 100 years, but this has not been proven.
Great whites are decreasing in numbers and are rare due to years of being hunted by man. They are a protected species along the coasts of California, USA, Australia, and South Africa.
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