Whale Shark

Sharks are fish. They average 2-3 feet long and live everywhere from tropical to Polar Regions and from the top to the bottom of the Ocean. Sharks migrate. We think the magnetic fields help them find their way. Sharks have a flexible cartilaginous skeleton and their skin is covered with denticles (hooks for protection). They have a dorsal fin, pelvic fin, pectoral fin and tail fin. Many have a layer of skin that protects their eyes. If they don’t have this layer they roll their eyes back in their head. They have good vision, A shark’s ears are inside the head and good to hear deep low sounds. They have two nostrils for smell and can detect blood two miles away. They are sleek with pointed snouts and gill slits. They feel movements and detect electrical signals through the holes on their snouts. Their skin tubes with hairs detect movement. The barbells on the ends of their snouts are used to feel under the sand.
The spiracles are holes behind the eyes that suck water. Sharks have several rows of teeth
Shark babies are called pups. Some sharks are born alive and some sharks lay egg cases
Sharks are relatives of the RAYS with poisonous spines on their tails The whale shark is the largest fish, longer than a bus, 46 feet long and it has several hundred pups in one litter. It sucks water like a vacuum and filter feeds. The basking shark is the 2nd biggest fish. They have taste cells on bumps on the roof of their mouths
The spined pigmy shark is the size of a banana. Cigar sharks grow to 20 inches long. The pygmy shark gets 10 inches long. The manta ray can be 23 feet wide.
Sharks are most active at night and shark attacks are rare. The great white is the most dangerous and largest meat eating shark at 18 feet long. It is rarely seen. Included among the most dangerous are the tiger, bull, and white tip sharks. Bull sharks swim up rivers. The largest sharks eat plankton (basking shark and the whale shark)
The spiny dogfish shark stays inside its mother for 2 years. It lives the longest at 100 years. In 1991 a soupfin shark was recaptured that had been tagged and it was 41 years old, The Megalodon is a prehistoric shark that was 50 feet long.
Spiny sharks and frilled sharks are deepwater fish. Cookiecutter sharks are luminous. The megamouth is the rarest. There have been only 14 seen since 1976. The inside of their mouth glows to attract prey. Nurse sharks pile together and rest in the daytime. Reef sharks have black tips (Cat sharks, hound sharks, baleen sharks, soup fin sharks, saw sharks, leopard sharks).
The BLUE SHARK can go 40 mph. The MAKO is the fastest at 60 mph and can jump out of water.
Two thirds of shark attacks happen in shallow water less than 6 feet deep. Divers study sharks in chain- mail suits in cages. The smell of blood attracts sharks. You should avoid shiny clothing that can be mistaken for fish scales.
Many sharks are killed by people. Fish nets trap and kill them – about 100 million a year. Pollution of chemicals from industry, sewage, oil leaks, and reef loss are a threat to the survival of sharks.