Coral reef

35 to explore

• Watch Animal Blacktip reef shark The blacktip reef shark is a medium-sized shark of warm, shallow coral reefs in the Indian and Pacific Oceans. You can spot it by the black tips on all its fins. It hunts fish, squid and crabs, stays close to its home reef, and gives birth to just a few live pups at a time.
• Watch Animal Blue sea star The blue sea star is easy to spot on Indian and Pacific Ocean reefs: bright blue, with five smooth, tube-shaped arms. It cleans up the reef by eating dead animals, tiny creatures and the thin film that grows on rocks, and it can grow back an arm it loses.
• Watch 3D Animal Blue tang The blue tang is a royal-blue reef fish with black markings and a bright yellow tail. It lives on coral reefs across the Indian and Pacific Oceans, starts life yellow, and carries sharp blades at the base of its tail.
• Watch 3D Animal Chambered nautilus The chambered nautilus is a relative of octopuses and squids that lives inside a coiled shell full of sealed rooms. It moves up and down along deep reef slopes by changing how much gas and water are in its shell, and it finds food mostly by smell.
• Watch Animal Christmas tree worm The Christmas tree worm is a small sea worm that lives in a tube inside living coral on Caribbean reefs. Only its two colorful, spiral crowns show. They catch tiny floating food and help it breathe, and the worm pulls them in with a flash if anything comes too close.
• Watch 3D Animal Common octopus The common octopus is a soft-bodied mollusc with eight sucker-lined arms. It lives in coastal waters, hides in a den by day, hunts snails and clams at night, and can change its color, skin texture and shape to vanish against rocks or sand. It lives only one to two years.
• Watch Animal Crown-of-thorns starfish The crown-of-thorns starfish is a large sea star of Indian and Pacific Ocean reefs, with up to 21 arms and hundreds of sharp, toxic spines. It eats living coral by pushing its stomach out over it. Usually it is a normal part of the reef, but sometimes huge numbers appear, called outbreaks, and they can eat much of a reef's coral.
• Watch Animal Dugong The dugong is a large, slow marine mammal that grazes on seagrass meadows in warm, shallow coastal seas from East Africa to the western Pacific. It is a relative of the manatee and, surprisingly, more closely related to elephants than to cows. It has a whale-like tail, a big bristly snout and very good hearing.
• Watch Animal Emperor angelfish The emperor angelfish is a striped reef fish from the Indian and Pacific Oceans. Adults are blue with bright yellow stripes, a yellow tail and a dark mask across the eyes. Young ones are dark blue with white and blue rings, and they change color as they grow. Emperor angelfish nibble sponges on the reef.
• Watch 3D Animal Epaulette shark The epaulette shark is a small, slender shark of Australia's Great Barrier Reef. It has a big black spot ringed with white above each front fin, and it can 'walk' along the reef, and even out of the water, by wriggling and pushing with its paddle-shaped fins. It can survive for a while in water with very little oxygen.
• Watch Animal Giant clam The giant clam, Tridacna gigas, is the largest clam alive. Its shell can grow more than a meter long. It sits on sunny coral reefs in the Indian and Pacific Oceans and gets most of its food from tiny algae living in its body. It is Critically Endangered.
• Watch Animal Giant oceanic manta ray The giant oceanic manta ray is the largest ray in the world, with wing-like fins that can stretch more than 6 meters from tip to tip. This gentle filter feeder funnels plankton into its wide mouth, and it has a single pup only every two to three years.
• Watch Animal Great hammerhead The great hammerhead is the biggest of the hammerhead sharks. Its wide, flat head, called a cephalofoil, holds its eyes far apart and is packed with senses that help it find stingrays hiding in the sand of warm, shallow seas.
• Watch Animal Greater blue-ringed octopus The greater blue-ringed octopus is a small octopus that lives among rocks and reefs in the western Pacific. Most of the time it hides, but when it is bothered, about 60 blue rings flash on its skin. The bright rings are a warning, and they tell us this is an animal to watch, never to touch.
• Watch Animal Green sea turtle The green sea turtle is the largest sea turtle with a hard shell. It lives in warm seas around the world and, unlike other sea turtles, grown-ups eat mostly seagrass and algae. Females swim hundreds or even thousands of kilometers to lay their eggs on the beaches where they hatched long ago.
• Watch Animal Grooved brain coral The grooved brain coral is a reef-building coral of the Caribbean, the Bahamas, southern Florida and Bermuda. Its tiny polyps live in long, winding valleys, which give the dome-shaped colony the look of a brain. A coral disease that spread from Florida since 2014 has hit it hard, and it is now critically endangered.
• Watch 3D Animal Hawksbill sea turtle The hawksbill sea turtle lives in warm seas around the world, mostly near coral reefs. Its pointed, hawk-like beak reaches into cracks in the reef to find sponges, its favorite food. Its beautiful patterned shell once made it a target for hunters, and today it is critically endangered.
• Watch Animal Humphead wrasse The humphead wrasse is the biggest fish in the wrasse family, up to about 2.3 meters long. Adults have thick lips, a forehead hump and wavy lines on the face. They eat shellfish, sea urchins and even toxic crown-of-thorns starfish, and many change from female to male. Too many have been caught, so it is endangered.
• Watch 3D Animal Lined seahorse The lined seahorse is a small fish of the western Atlantic Ocean, from Canada and the United States down to Brazil. It has a horse-shaped head, a long snout with no teeth and a tail that grips seagrass. The male carries the eggs in a pouch until tiny seahorses are born.
• Watch Animal Magnificent sea anemone The magnificent sea anemone is a large sea anemone of warm Indian and Pacific Ocean reefs. Its body is a soft column topped with hundreds of finger-shaped tentacles, and it often perches on top of rocks in plain view. Many kinds of clownfish live safely among its stinging tentacles.
• Watch Animal Mandarinfish The mandarinfish is a small, shy fish from the coral reefs of the western Pacific Ocean. It has no scales; instead its skin is covered with slimy mucus and painted with swirling blue, orange and green lines. It hops along the reef bottom on fan-shaped fins, picking up tiny animals, and at dusk males and females rise together to release their eggs.
• Watch Animal Moorish idol The Moorish idol is a tall, flat reef fish with bold black, white and yellow bars, an orange patch on its snout and a long white fin that trails behind it like a ribbon. It lives on reefs across the Indian and Pacific Oceans, from East Africa to the coasts of the Americas, and uses its tube-like snout to pick sponges and small animals from cracks.
• Watch Animal Ocellaris clownfish The ocellaris clownfish is a small orange-and-white reef fish from the Indian and Pacific Oceans. It shelters among the stinging tentacles of a sea anemone, protected by a slimy coat, and every clownfish starts life as a male.
• Watch Animal Orange clownfish The orange clownfish is a small, bright orange reef fish with three white bands edged in black. It lives in the warm western Pacific, from northern Australia to New Guinea and the Solomon Islands, always beside a sea anemone. A coat of slimy mucus keeps the anemone's stings from hurting it, and the fish and anemone help each other.
• Watch Animal Peacock mantis shrimp The peacock mantis shrimp is one of the most colorful animals on coral reefs in the Indian and Pacific Oceans. It is famous for its club-shaped arms, which strike so fast that they can smash snail shells, and for its amazing eyes on movable stalks.
• Watch Animal Red lionfish The red lionfish is a striped reef fish with long, spiny fins that spread out like a lion's mane. It comes from the Pacific and eastern Indian Oceans, where it hunts small fish and shrimp at night. People released lionfish into the Atlantic Ocean, and there they have spread fast, eating many native reef fish.
• Watch 3D Animal Reef stonefish The reef stonefish is a master of disguise. Its lumpy, warty skin and rocky colors make it look like a stone or a piece of coral on the sea floor. It waits without moving until a small fish or shrimp comes near, then gulps it in a flash. Sharp spines on its back protect it from enemies.
• Watch Animal Southern stingray The southern stingray is a flat, diamond-shaped ray of warm western Atlantic waters, from the eastern United States through the Gulf of Mexico and the Caribbean to South America. It spends much of its time on sandy bottoms, finding buried crabs, shrimp and fish by smell, touch and tiny electric signals.
• Watch Animal Spot-fin porcupinefish The spot-fin porcupinefish is a spiny relative of the pufferfish that lives on warm reefs all around the world. Its spines usually lie flat, but when it is threatened it swallows water and swells into a prickly ball. At night it uses a strong, beak-like mouth to crack open snails, hermit crabs and sea urchins.
• Watch 3D Animal Spotted eagle ray The spotted eagle ray is a ray that 'flies' through warm Atlantic waters by flapping its wide, wing-like fins. Its dark back is covered in white spots, its tail is long and whip-like, and its snout looks a bit like a duck's bill, which it uses to dig for clams and other shellfish.
• Watch Animal Staghorn coral Staghorn coral is a reef-building coral of Florida, the Bahamas and the Caribbean. Each colony is made of many tiny polyps that build a branching skeleton like a stag's antlers, and tiny algae living inside them give it food and color. Once one of the most common Caribbean corals, it is now critically endangered.
• Watch 3D Animal Tiger shark The tiger shark is one of the biggest sharks in the sea. Young tiger sharks have dark spots and stripes like a tiger, which fade as they grow. It eats an amazing range of food, and it travels long distances between warm and cooler seas.
• Watch 3D Animal Whale shark The whale shark is the largest fish in the world. This gentle giant swims through warm seas with its huge mouth open, filtering tiny plankton and small fish from the water, and every whale shark has its own pattern of pale spots.
• Watch Animal Yellow boxfish The yellow boxfish lives inside its own box: a hard shell of bony plates joined together, with holes for its eyes, mouth and fins. Young boxfish are bright yellow with black polka dots, and big adults turn bluish. Its skin can release a toxic slime that protects it from predators, and it paddles slowly around reefs nibbling algae and small animals.
• Watch Animal Yellow tang The yellow tang is a lemon-yellow surgeonfish of Pacific coral reefs, most common around Hawaii. It grazes on algae all day, which helps keep reefs from being smothered by seaweed, and it has a sharp white spine on each side of its tail for defense. It is one of the most collected fish for home aquariums.