We explain what the white shark is, its habitat, reproduction and other characteristics. Also, how frequently it attacks humans.
What is a white shark?
The white shark or great white shark is the largest and most ferocious fish species of all marine predators. Its scientific name is Carcharodon carcharias.
This animal emerged around 16 million years ago in the Neogene period, and comes from one of the oldest known lineages of fish, a relative of the extinct prehistoric shark known as megalodon either megalodon.
Although the white shark is very present in our imagination, as the protagonist of stories and films set in the sea, not much we know about its life and behavior. partly because These are solitary animals, which do not form schools.
On the other hand, their cartilaginous body completely decomposes when they die, except for their fearsome bony jaws, equipped with pointed, serrated teeth.
See also: Sea animals
Characteristics of the white shark
The main characteristics of white sharks are:
- have an aerodynamic body shaped like a torpedo, which allows them to swim at speeds of up to 25 kilometers per hour, thanks also to their powerful tail and robust body. usually measure between 5 and 7 meters in length although cases of particularly large adults (around 11 meters) have been seen, weighing between 1.75 and 2 tons.
- have a very characteristic dorsal fin which can protrude from the water when the fish swims near the surface, and two others on the sides of similar size. Its slate gray body is rough to the touch, and ideal for camouflage on the rocky seabed of certain coasts, except for its white belly, from which its name comes.
- They have a large, arch-shaped mouth. Over there have about 300 triangular and serrated teeth very wide, arranged in several successive rows. Its bite is estimated to have between 12 and 24 tons of force (300 times the human bite), and up to 14 kg of meat can be put into the mouth in a single bite, given that when attacking the jaw it opens so much that it can deform the head. of the animal, projecting forward.
- Your senses are particularly acute and pick up vibrations in the surrounding water. In addition, they have an extraordinary sense of smell, capable of catching a drop of blood in the water from miles away.
- white sharks do not have a swim bladder so it must be in constant movement so as not to sink, and so that water enters through its always half-open mouth and comes out through the gills, oxygenating its immense body.
White shark habitat
The white shark lives almost exclusively in areas near the coast where light and life abound, thus allowing it constant access to its prey.
Their metabolism allows them to stay slightly warmer than water, but not enough to populate the icy waters of the Arctic or Antarctic, which is why they are not usually found in these regions. However, yes can descend into colder waters up to 1 kilometer deep being able to colonize food niches with less competition.
It is common to find white sharks in the seas near the Lesser Antilles, in the Atlantic region east of the Caribbean, as well as in regions of the Greater Antilles, such as the Gulf of Mexico, Florida, Cuba and the East coast of the United States. They are also common on the South American coastal strip, from Rio Grande do Sul to Argentine Patagonia, as well as on the Pacific Ocean coasts of the western region of the United States, or South America (from Panama to Chile).
In addition, they are very abundant in the Great Barrier Reef in Oceania, as well as in Pacific archipelagos in Hawaii, Fiji and New Caledonia, Australia, Tasmania, New Zealand, along the entire Asian and African coastline (especially in South Africa and in the mouths of the Congo and Volta rivers).
White shark reproduction
The white shark breeds preferably in temperate waters, during spring or summer. Its reproduction is ovoviviparous, that is, through internal fertilization of the eggs within the female where they mature until they hatch and then the offspring is expelled from the mother's body.
Gestation of this species takes about a year and around three or four young are usually born at a time, quickly moving away from the mother so as not to serve as prey. Cannibalism is common in this species, and can occur even inside the mother's womb, where the strongest offspring devour the weak ones or eggs that have taken too long to open.
White shark feeding
As we usually imagine them, white sharks are fierce and solitary hunters. They tend to swallow their victim more or less whole, or tear off large pieces to swallow, since they are unable to chew.
Their diet is 100% carnivorous and is made up of large marine mammals, such as seals and sea lions, although they can also eat cetaceans, turtles, dolphins, porpoises, penguins, different types of tuna, other sharks, or fish and rays during their youth.
They may eventually feed on carrion. In addition, they can mistakenly swallow a wide variety of objects, from plastic pots to license plates.
Natural enemies of the white shark
Not much is known about the social patterns of the white shark. However, the discovery of bite marks from other species suggests that there could be some territorial competition with whales and other cetaceans large size.
In principle, they are solitary animals, with ferocious behavior even among peers. Its main enemy is humans due to their indiscriminate hunting accidental fishing or water pollution.
Great white shark attacks on humans
Contrary to what the movies suggest, white shark attacks on humans are rare and accidental. They are usually due to the animal confusing a surfer with a seal, or distrusting the presence of a diver and proceeding to bite it as a “warning”.
Furthermore, they are very rare animals, so encounters with them are rare, unlike what happens with other species of sharks, such as the tiger shark or the bull shark.
White shark endangered
Given the low density of its populations and its bad reputation, the white shark has been a victim of humans for decades. Due to occasional fishing, to water pollution (it is common to find remains of garbage inside their corpses), to massive fishing with nets or the extinction of their natural prey the number of white sharks is declining.
They were included on the IUCN red list of endangered species for the first time in 1990, and since 1996 they have been considered “vulnerable”, that is, is currently in danger of extinction by the hand of the human being.
Continue with: Sea animals
References
- “Carcharodon carcharias” in Wikipedia.
- “White Shark” in National Geographic.
- “Australia. The Great White Shark” (video) on Planet Doc.
- “White shark (Carcharodon carcharias)” in Oceana, protecting the world's oceans.
- “Great White Sharks” at World Wildlife Fund (WWF).
- “White Shark (fish)” in The Encyclopaedia Britannica.
