Origin
The great white shark (Carcharodon carcharias) is part of the family Lamnidae, the order Lamniformes. It belongs to a family of very fast swimmers and is known as the largest carnivore on earth after the whale. It is a fish with a large territory that lives in the Atlantic, Indian and Pacific oceans. It can be found from the tropics to the polar circles in deep waters.
It is among the most famous and well-known species of sharks. It can be found in foreign or specialized literature under the names: White Shark, Great White, great white shark, White Death, White Sea Dog(Australia), Blue Sea Dog(Africa), the great white shark, the great white, white pointer, white shark or white death.
At the moment the number of sharks is declining and the species is vulnerable to extinction. In Brazil, Namibia, South Africa, California and Australia, laws have been passed to protect this species of shark. A white shark tooth sold for $ 1000 in Australia, and a complete set of teeth for $ 20,000.
The vast majority of sharks die in the fishing nets of commercial vessels. Millions more sharks are hunted annually to cater to snobs. No white shark lives in captivity for more than one to two weeks.
A 2014 study estimated the population of white sharks off the California coast at 2,400. The White Shark is known as the "gentleman of the oceans" !
White Shark feed
The great white shark is a fearsome predator for both man and his prey. It feeds on a large amount of food because it is greedy. The food consists of a wide variety of fish, other sharks, seabirds, turtles, mammals (seals, sea lions, otters, etc.).
The preferred method of attack is from behind. It comes at speed and bites its prey causing it deadly wounds. She eventually dies from losing too much blood. The food is torn and swallowed in pieces. A meal the size of a sea lion or seal can keep them hungry for a month.
Appearance White Shark
The Great White Shark reaches maturity at 6.5 meters in length and weighs almost 2500 kg. One of the reasons it is known is its impressive size. The ancestors of this fish were three times larger reaching lengths of over 8 metres, weighing 3300kg and teeth of 16cm. The mouth ends with several rows of teeth. When he loses a tooth because he falls out or loses it when he bites from a boat, another takes his place. The eyes are black.
It has five lateral gills through which it breathes. The body is dark gray on the dorsal side (i.e. on the back), and the belly is white. The mouth has about 3,000 teeth arranged in several rows. He uses the front rows when attacking. The last two rows replace the others with time when they fall, break or chop. A shark changes up to 26,000 teeth in a lifetime. This is because they are not trapped by a bone plate or in the alveoli, but are trapped in a fibrous membrane.
Like many species of fish, sharks do not have warm blood. They have a rich network of blood vessels, called the Mirable network, located in the muscles with which the body temperature increases by 10 degrees above the temperature of the environment in which they are. The eyes are not very well developed, they are used more during the day. He has the ability to rotate his eyeball and is generally curious.
Although he prefers to walk mostly during the day, he is sometimes seen at night. The eyes are protected by a very thick membrane. You can see scratches around the eyes, but not on the eyeball. The animal can also see out of the water. It is said that he sometimes pulls out his head to observe the surroundings.
The smell is very well developed. Sharks can sense blood from far away. It is said that a shark can feel a drop of blood from 7km (if favored by currents). Because of its highly developed senses it is called "nose that swims" or "ears that swim". It has a" listening system " that detects vibrations. With Lorenzini's ampoules (small channels near the nose) they can detect the electric fields emitted by heartbeats. They say sharks have these organs so sensitive that they know where North and South is.
It is said that thanks to the triangular fins curved in the back and the spindly body these sea monsters glide in the water like torpedoes. The symmetrical tail (unlike other shark species that have asymmetrical tail) is a rarity among sharks. The shark's" most prized possessions " are its huge conical head and mouth full of teeth.
White shark behavior
The great white shark can be easily identified by its white spots, size and shape of its teeth. The shark uses the teeth on the lower jaw to hold the prey and the teeth on the upper jaw (triangular in shape) to tear the prey apart. A shark over 6 meters can bite with a force of 10,000 Newtons.
It is a diurnal active fish. It is considered by man one of the most dangerous sharks due to its size, aggressive behavior, the fact that it swims in shallower waters in search of food and its weapon (teeth).
Although it is considered one of the most dangerous sharks, it is not so. Many divers said it was a curious but predictable fish. Those who have had the opportunity to live and see or study a great white shark live say it is a gentleman of the oceans.This fish inspires respect, not fear, but the world doesn't know it.
The white shark became popular in Steven Spielberg's famous 1975 film Jaws. Since then, there has been an attempt to study it. It is an agile, intelligent and strong shark. A tagged specimen was tracked over a distance of 19,000 km. The acperita surface is smaller, but it is also very large. The shark descended to a depth of 900 meters. This means that it has the ability to swim in varied waters in terms of temperature.
The average speed of movement of a shark is 30km/h, but when chasing a prey can reach 60km / h. it is a great effort and a huge energy consumption if you think that this animal has over 2000 kg. Hopefully people's behaviour will be positive in the future and scientists will be able to study the unique and fascinating behaviour of this fabulous fish.
Cage diving tourism is frequented in South Africa, South Australia and California. These practices of observing sharks are beginning to gain popularity.
The shark is a sanitary of the seas. It cleans the oceans of dying or sick creatures. A shark population means clean oceans and seas.
White shark breeding
Little is known about the mating season of sharks. It does not survive in captivity, and studying it in the natural environment is difficult. The mating season seems to be in Spring-Summer. The great white shark is said to reproduce twice in its lifetime.
Unlike many other species of fish that spawn in Sharks, fertilization is internal. Male sharks have two copulatory organs called pterygopods that use them to transfer sperm into the female's body. These organs are used in turn because the female has only one genital organ.
Following the gestation period the female gives birth to 9-11 Cubs. White sharks are ovoviparous, that is, they give birth to live Cubs. The little one enters into his duties from birth. He comes into the world with a pair of teeth that help him feed.
The length of the offspring at birth is about 1.4 meters. After birth they no longer have any contact with their mother. The shark is thought to have the longest gestation period of any terrestrial animal.
Researchers at the University of New South Australia have studied shark pups smaller than 3 meters and noticed that they avoid attacking large fish or seals because of their jaws and teeth that are too weak for such large prey.
It seems that the species has a much faster body growth than the natural hardening of cartilage. This is why young people have to be content with smaller fish or prey for the first 15 years of life. Sexual maturity is reached at the age of 15.
An analysis found that the maximum age the great white shark can reach is 72 years. It has also been tried to evaluate age by the Rings of the vertebrae but this method is not very accurate because sharks have periods of developmental stagnation. Life expectancy is 40-70 years.
