In fact the world´s largest animal lives in the sea. It is the blue whale, which can be over 33 metres long. That is longer than a tennis court ! A blue whale can weight more than 150 tonnes- which is heavier than 30 elephants.
Whales are not fish. They are large mammals that live in sea water. Whales have big heads, large bodies, and tails shaped like triangles. They use their powerful tails to move forward.

These animals breathe air through lungs as all mammals do. They come to the surface of the water to breathe out of a blowhole at the top of their head. This can cause a huge spout of water – as high as 15 metres for some whales. Whales come up to breathe about every 15 minutes. You may think the blue whale must eat great fish, but in fact it eats only tiny creatures like shrimps which are called krill.
During the last hundred years almost half a million blue whales have been killed for their meat and oil. The blue whale is now a protected species. This means that nobody is allowed to kill it.

Did you know?
Killer whales , or orca can jump up to 5 metres out of the water
Instead of teeth, blue whales and some others have strips of whalebone,called baleen.
Killer whales are not known to have ever killed a human.