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Crocodiles and alligators

Nile crocodileNile crocodile Crocodilians are aquatic, predatory reptiles with long jaws and bony plates of armour on their bodies. The family includes crocodiles, alligators, gharials and caimans. Most live in tropical rivers and lakes. The largest species are the Nile crocodile and the saltwater crocodile, both of which grow up to 7 metres (23 feet) long. They can easily bring down large prey such as antelope, which they ambush at the water’s edge, dragging them underwater to drown. Crocodiles are expert swimmers, but can also run at speed on land.

Nile crocodileNile crocodile
A crocodile attacks a young wildebeest.A crocodile attacks a young wildebeest.


Crocodiles feed on a wide range of prey, including fish, turtles, birds and mammals. Having eyes and nostrils on top of their heads allows them to lie in the water with their bodies almost completely hidden.

They also have transparent “third eyelids” which closes to protect their eyes when they submerge. They can close off part of their throats to avoid swallowing water while feeding.

Crocodiles lie in the water, waiting for their prey to come down to the water to drink. They lunge out with their powerful jaws, dragging their prey into the water to drown. Then they tear them apart with their teeth. Crocodile jaws can bite with immense force. They have by far the strongest bite of any animal—12 times more powerful than a great white shark.

A crocodile’s lower teeth fit into notches in the upper jaw, but its fourth tooth is visible when its mouth is closed. In an alligator, the teeth fit inside the mouth and cannot be seen.

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