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Great White Shark
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attacks more on people than any
other type. |
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averages 12 feet long and 3,000
pounds. |
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unlike most sharks, it can lift its
head out of the water. |

Look
at the damage the Great White shark did to this seal!
GENERAL DESCRIPTION
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, 5 gill slits, no fin spines, an anal fin,
and 3 main fins: the dorsal fin (on its back) and 2 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.

COLORATION
Only the underbelly of the great white shark is actually white; its top surface
is gray to blue gray. This is useful in hunting its prey. The great white
usually strikes from below and its grayish top coloration blends in with the
dark water, enabling it to approach the prey unobserved.
SIZE
Great whites average 12-16
feet long (3.7-4.9 m) long. The biggest great white shark on record was 23 feet
(7 m) long, weighing about 7,000 pounds (3200 kg). Females are larger than
males, as with most sharks. Shark pups can be over 5 feet (1.5 m) long at birth.
DIET AND FEEDING HABITS
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 2 months.
TEETH
The great white shark has 3,000
teeth at any one time. They are triangular, serrated (saw-edged), razor-sharp,
and up to 3 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.
SENSES
Shark's 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
liters) 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.
GREAT WHITE SHARK ATTACKS
Most great white attacks are not fatal. Great whites account for about 1/2 to
1/3 of all 100 annual reported shark attacks. Of these 30-50 great white
attacks, only 10-15 people die.
SOCIAL GROUPS
Great whites are usually solitary animals but are occasionally spotted traveling
in pairs.
HABITAT
Great white sharks are found near shore along most of the temperate (not very
hot and not very cold) coastlines around the world.
DISTRIBUTION
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.

MIGRATION
In the fall, some females migrate to warmer waters (for example, southern
California) to give birth.
SWIMMING
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 2 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.
It has been recently discovered that great white sharks can
jump out of the water. They jump into the air from deep water in order to catch
fast-swimming seals
REPRODUCTION
Great white sharks
give birth to 2-14 fully-formed pups that are up to 5 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 unfertilized 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.
LIFE SPAN
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.
POPULATION COUNT
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.

Look at the Great White Shark's teeth!
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