Great White Shark Information
The great white shark, a ferocious killing machine, yet very different from how the media portrays it. A terrifying yet fabulous creature!
The first thing that one thinks of when thinking about the Great White Shark is the terrifying scenes from the movie Jaws. Its deadly jaws devouring a lone woman swimming out at sea. Its ferocious appetite for humans.
But in reality, the Great White Shark (Carcharodon carcharias) does not attack and eat humans in its normal course of behavior. It has been much maligned by the media, turning it into a terrifying underwater predator, that hunts humans. According to a study done in the Unites States of America, out of every 100 shark attacks in a year, only 30-40 are by the Great Whites. And only 10-14 out of them are fatal. Looking at it in another way, it can be said that more humans are killed every year by dogs in the U.S., then by the Great White Shark. Nonetheless, the Great White Shark is a fabulously equipped killing machine.
Sharks have existed for more than 350 million years. They have thrived for millions of years as specialized and highly efficient hunters. The Great White Shark of the Lamniformes order and the Selachii family, is the world’s largest predatory fish, and on the average grows to between 12 to 16 feet. There have been records of sizes as big as 23 feet, and from jaw imprints on whales it is estimated that there are even larger specimens. These huge underwater predators, weigh more than 2000 kg on the average.
It is a streamlined swimmer, with a torpedo shaped body, a pointed snout and a crescent shaped tail. Unlike most other fish it does not have any internal bones, but has a cartilaginous skeleton. Its dorsal fin and part of the tail are visible above the water. The fin that has terrified many in movies and in real life. The great white is actually grayish in color, except for a white underbelly. This is surprising considering its name. The reason for such coloring is that having a gray-blue to brownish–gray color on the top portion of its body is useful for it to camouflage itself.
This huge and powerful shark is propelled through the water by its powerful tails. Its fins are only used for balance. They do not swim like other fish, but move almost like an aircraft in continuous flight. They average about 2 mph (3.2 kph) but can swim 15 miles per hour (24 kph) in short bursts. And these predators constantly swim, as they will sink otherwise. They do not have air filled bladders, like other fish, to keep them afloat, but do have a large and oily liver that provides some buoyancy. They literally propel themselves through the water all of their lives, and cannot really come to an abrupt stop or swim backwards due to the stiffness of their fins.
An interesting feature of the Great White is their teeth. They are actually a fearsome set of teeth. At any given time they have at least 3000 teeth. Most of which are about 3 inches long. They are triangular, serrated (saw-edged), razor-sharp and are placed in several rows. The first two rows pull the prey in and the third row comes into play afterwards. Their teeth are not for chewing, and the Great Whites just tear away chunks of food that fit into its mouth and swallow it whole.
The Great White Shark has an extraordinary sense of smell. It can smell a drop of blood in 25 gallons (100 liters) of water. The nostrils of sharks are only used for smelling, and not for breathing. The Great White breathes through its gills. Another acutely developed sense in the Greta White is their ability to sense electric charges. Even small electrical impulses emanated by the movement of muscles by animals can be detected by the Great Whites. These electrical impulses are sensed by a series of jelly-filled canals in the head called the ampullae of Lorenzini.
The Great White though believed to attack and hunt humans actually feeds mostly marine mammals such as pinnipeds (seals and sea lions). Their common prey include harbour seals, northern elephant seals, sea lions, and others. The adults also commonly eat small toothed whales (like belugas), otters, sea turtles and dead water animals. The Great White often feed on dead animals such as baleen whales and other large cetaceans. The young sharks feed on fish, rays, and other sharks, and as they grow, switch to feeding on marine mammals and scavenging on large animal carcasses. A good meal by Great White standards will keep it satisfied for about two months.
The young of sharks come out as fully developed sharks from the females body. These pups are about five feet in length. The Great White sharks are ovoviviparous. 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. Females usually give birth to 2-14 young, which separate from the mother immediately after birth, and fend for themselves. The Great White’s life span has never been ascertained, but some people believe that it lives for a hundred years.
These complex creatures of the water are usually solitary animals but are occasionally spotted traveling in pairs. Great white sharks are found near shore along most of the temperate (not very hot and not very cold) coastlines around the world. It can be said that they are found nearly worldwide in temperate waters. Especially 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.
Though a fearsome predator, the Great White shark is slowly vanishing. They are decreasing in numbers and are rare due to years of being hunted by man. They are now a protected species along the coasts of California, USA, Australia, and South Africa.