Shark Facts!!

Sharks have between 5 and 7 gill slits on each side of their body in front of their pectoral fins. Bony fishes only have one pair. Having many exposed gill slits probably helps transfer more oxygen into their blood faster which allows them to swim very fast when they need to.


Most shark's skin is covered in small denticles instead of scales. Denticles are a lot like teeth. They have dentine in the centre and enamel on the surface. This makes shark's skin very tough and abrasive like sandpaper. The shape and position of some shark's denticles also helps reduce friction so that they can slip through the water easier.


Sharks have an extra sense that is able to detect tiny electric fields. They can use this to find food that is buried or to search for animals to eat in the dark or in turbid water. Sharks and rays make up the sub-class of fishes called elasmobranches. This sub-class is part of a class of cartilaginous fishes called Chondrichthyes which also includes chimaeras (ratfishes).


How dangerous are sharks?

• Sharks are usually very wary of people and most sharks will swim away long before you see them.
• There are nearly 500 species of sharks but only a few are likely to be involved in an attack. Some of the more dangerous sharks include the Great White Shark, the Tiger Shark, and the Bull Shark.
• Sharks do not normally treat humans as food. If they did, it would be very easy for them to eat all of the people who play in the water at the beach because they are much better swimmers than we are. Most scientists agree that attacks are usually the result of mistaken identity or the sharks feeling threatened because they are cornered. In places like California where there are a lot of White Shark attacks on surfers, scientists believe that the sharks think that the surfers look like seals or sea lions.

What do sharks eat?

• Sharks and rays have a very varied diet. They are carnivores which means that they eat animals rather than plants and algae. Some sharks commonly eat bony fishes, crustaceans (crabs, lobsters, and other animals with an external skeleton), mollusks (snails, sea slugs, octopus and squids), and different types of worms. 
•  A shark's diet is often determined by its habitat. For example, sharks that live out at sea (pelagic sharks) are more likely to eat fish and squid because that is all that is available.