Underwater Cities

One place that fish live together is a coral reef. Coral reefs are warm, clear, shallow ocean habitats that are filled with sea life. A reef is formed from coral polyps, tiny animals that live in colonies. When coral polyps die, they leave behind hard, stony, skeletons made of limestone. Over time, these skeletons join together to form the reef.

The coral reef provides shelter for many animals, including sponges, fish, jellyfish, anemones, starfish, crabs, shrimp, lobsters, turtles, sea snakes, snails, octopuses and clams. The reef also provides food for land creatures such as birds who also feast on coral reef animals.