This page is a coral reef in warm, shallow sea. Move your pointer across the sand and your animal will swim after you. Choose a different animal at the bottom, and tap the notes to open them.
The Great Barrier Reef right now checking the sky…
It lives in a sea anemone whose stings would kill other fish. A coat of slime protects the clownfish.
The anemone gives shelter. In return, the fish chases off its enemies and feeds it scraps.
All clownfish are born male. When the female of a group dies, the biggest male turns into a female.
The largest fish in each anemone is the female, and she is the boss.
The male fans the eggs with his fins and guards them until they hatch.
A clownfish rarely strays more than a few metres from its anemone in its whole life.
Meet them all
Amphiprion ocellaris
A small, bright orange fish with three white bands edged in black. It lives among the tentacles of a sea anemone.
Octopus cyanea
A soft-bodied animal with eight arms, a bag-like body and skin that changes colour in a blink.
Hippocampus kuda
A small, upright fish with a head like a horse, armour of bony rings and a tail that curls round things.
Scaridae
A chunky, brightly coloured fish, often blue-green and pink, with teeth joined into a beak like a parrot's.
Gymnothorax javanicus
A long, thick, snake-like fish, brown with darker spots, that lives in holes in the reef with its head poking out.
Pterois volitans
A fish striped in red-brown and white, with long, feathery fins and a row of venomous spines along its back.
Through the year
Reef animals are there all year: the water is always warm. The animal following you is shown in red.
Good to know
A coral is a colony of tiny animals called polyps, each like a small sea anemone, living in a stony cup.
Tiny algae live inside the coral and make food from sunlight. They give coral its colour.
The Great Barrier Reef, off Australia, is 2,300 kilometres long: the biggest thing ever built by living creatures.
If the sea gets too warm, corals lose their algae, turn white and may starve. This is coral bleaching.
Much of the white sand on tropical beaches is coral that has been through a parrotfish.
After dark the day fish hide, the corals put out their tentacles, and the octopus comes out to hunt.
Real photos of the animals on this page. Tap one to see it bigger.
Photos are from Wikimedia Commons and are used under free licences. They have been resized, and cropped where they appear in link previews. Open a photo to see who took it.
Coral reefs cover less than one per cent of the sea floor, yet about a quarter of all the kinds of sea fish live on them. The reef itself is alive: built, very slowly, by animals smaller than a pea.
Back to the topOpen ocean animals live on the Open ocean page: choosing one takes you there.
These live somewhere else: choosing one takes you to their page.
Animals from other parts of the world live on their own pages: change area.