Sharks, both dangerous and docile, live in oceans and seas. Most sharks live in the Atlantic Ocean. The study of sharks, ichthyology, finds that, as of 2011, there are approximately 400 species of sharks in the world's oceans. New shark species are discovered frequently, according to the Florida Museum of Natural History ichthyology department.
The basking shark lives almost exclusively in the Atlantic Ocean. The basking shark is the second largest shark species in the world, second only to the whale shark. Growing as much as 40 feet in length at full maturity, the fish can weigh up to 19 tons. The shark typically swims slowly at the surface of the water, its mouth wide open near the shore. The shark's huge mouth billows out to catch small fish and plankton in the water, like a baleen whale.
Atlantic Sharpnose Shark
The Atlantic sharpnose shark lives almost exclusively in the Atlantic, but can also be found swimming in the Gulf of Mexico. A small shark, it usually only grows to about four feet long, from nose to tail. Because it is not a preditor shark, the sharpnose it eats only small fish, mollusks and shrimp. It is a slender shark with brown or grey colouring. It has five gill slits, two dorsal fins and the mouth located behind the eyes.
While the blue shark swims in the Atlantic, is more commonly found in tropical, deeper waters as it prefers temperatures around 6.67 to 13.9 degrees Celsius. The blue shark is one of the most easy to recognise sharks and is attractive to some, because of its deep indigo blue colouring. From above looking down on the shark, it is blue; from underneath looking up at its belly, it is white. A slim and quick shark, the blue shark grows to around 13 feet at maturity.
Great Hammerhead Shark
The great hammerhead is the largest of all the hammerhead species, which can grow to 18 feet long. Like other hammerheads, its most distinguishing feature is its horizontal head, with its eyes on the outermost part of its brow. While larger sharks may prey on young hammerheads, their only true predator is man, according to scientists at the University of Miami. As of 2011, the great hammerhead is thought to have declined in numbers by as much as 50 per cent in the last decade, according to the International Union for Conservation of Nature. The most endangered population are those sharks living in the Atlantic.
More Atlantic Sharks
Other sharks that live in the Atlantic include the great white, tiger and shortfin mako. The Greenland shark, which swims at depths of up to 2,400 feet below the surface, prefers frigid waters, and a tiny shark called the black dogfish lives exclusively in the Atlantic.