The Great White shark (Carcharodon carcharias) is part of the Mackerel Shark family, less commonly known as the Lamniformes, along with the Mako shark, Goblin shark, Basking shark and Thresher sharks. The Genus name Carcharodon comes from the greek words meaning ‘Ragged Tooth’ while the species name carcharias comes from the greek meaning ‘point of shark’ or ‘type of shark’.
Great White shark anatomy and appearance
Female Great White’s can reach lengths of over six metres and weigh up to two tons whereas males are slightly smaller, most of the time not growing past five metres. The strength of the great white shark’s bite is estimated at 1 ton per square inch. The snout is fairly short and cone-shaped. The rest of the Great White's body is torpedo-shaped and ends with a symmetrical caudal fin, or tail. The great white takes its name from its white belly, however it's not white all over. Great whites exhibit countershading. On top, it's grey, or sometimes brown. This coloring aids the great white as it stalks its prey. From below, the white underside blends in with the sky above, while from the top of the water, the shark is indistinguishable from the ocean floor below. Most great whites also have a black spot near their pectoral fin. Great white sharks have serrated bladelike teeth with the upper jaw containing a row of 23-28 teeth and their lower jaw 20-26 teeth. These triangular teeth can reach up to 6.6 inches in height.
Unlike other sharks and fish, the Great white shark is warm-blooded, meaning the vessels align concurrently (the vessels that run to the exterior of the body next to the vessels that return from the exterior). As the warm blood from the inside passes the cooler blood that is coming back from the exterior, it transfers its heat to the adjoining vessel, allowing the great white to keep its interior organs warm, this movement allows the great white shark to maintain a body temperature as much as 25 degrees Fahrenheit (14 degrees Celsius) warmer than the water. Being warm-blooded means they can live in slightly colder waters than other sharks, but it also means they need to eat more.
Great White shark habitat
Great White Sharks tend to live in tropical coastal and temperate regions, frequently Australia and South Africa. As Great White Sharks grow, their habitats change. When they are pups and juveniles they are more likely found in coastal and estuary habitats whereas when they are adults they prefer to live farther out at sea in pelagic, or open ocean, ecosystems.
Some individual white sharks may travel far out to sea or into tropical waters, but field studies show that most return to these temperate feeding areas each year.
Great White shark diet
Newborn white sharks feed on fishes and other sharks. As they reach adulthood, their prey includes sea turtles, seals, sea lions, porpoises, dolphins, and small whales. Prey is usually hunted by ambush, where the shark will attempt to rush the animal by surprise and inflict a sudden and massive fatal bite. Often this initial rush is so strong that the intense impact may send the prey out of the water or will send the shark into the air if it misses the target. The sharks will retire and wait for the prey to quickly die, giving rise to the terms bite and spit or bite and wait for this method of attack. White sharks are also opportunistic scavengers and will feed on the carcasses of whales and basking sharks; however, they are not indiscriminate.
Great White shark population
Great White Sharks can have a lifetime of up to 70 years, with males maturing at approximately 26 years old and females maturing at approximately 33 years old. However maximum lifespan is difficult to determine as some great white sharks can only live up to 30 years old. Great white sharks bear live young and females give birth to between 2 and 10 pups per litter, and perhaps as many as 14. Researchers think the gestation period is anywhere from 12-22 months which would only allow for breeding to occur approximately every other year. Pups are born approximately 4 feet long. The great white shark is ovoviviparous, which means that the shark grows in an egg, which is then hatched inside the mother. Shortly thereafter, the shark pup is born. While in the womb, great white shark embryos feast on unfertilized eggs, a practice known as oophagy.
Great White Sharks have a reproductive system known as internal fertilization. This means that the male shark will insert one of his two claspers (a modified pelvic fin) into the female's cloaca (a common opening for the reproductive, excretory, and digestive systems) to deposit his sperm. Great White Sharks are not monogamous and will mate with multiple partners during a breeding season.
The video below shows what could be the first ever footage taken of a new born Great White shark:
Great White shark conservation
Great whites are listed in CITES Appendix II, which makes it illegal to trade them without a permit. Historically they have been hunted for sport, and for their jaws, fins, liver, meat, and cartilage. Marine biologists lack exact numbers on the great white population, but they're seen very rarely and are currently listed as vulnerable, according to the International Union for Conservation of Nature and Natural Resources, with the overall population trending downwards. However, great whites are still regularly caught as bycatch by the inshore fishing industry and sometimes specifically targeted in shark culls.
Additional interesting information:
The great white shark is one of more than 450 shark species and is the largest of all predatory sharks in the ocean today.
Great whites play a special role in the ocean as a top predator by keeping prey populations such as elephant seals and sea lions in balance.
The presence of great white sharks ultimately increases species stability and the diversity of the ocean.
Great white sharks have such a strong sense of smell that they can detect a colony of seals two miles away.
Great White Sharks ancestry dates back more than 400 million years.
Although these sharks are often classified as loners, there is a degree of social hierarchy that does exist among them.
Female sharks often dominate males.
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