What are Sea Corals and Anemones?

The sea corals and sea anemones are in a group called coelenterates. The anemones are known as flower animals because of their colorful tentacles that are bright red, purple, yellow, and green.

They appear the most spectacular at night, because this is when they feed. At feeding time their numerous tentacles are spread open and waving. Tiny animals that come within reach are pulled into their mouth.

Learn how to identify coral reefs and help save them from extinction.

The sea anemone's body is covered with a tough leathery skin to help protect it. Usually it attaches itself to shells or rocks on the sea floor. But it can also glide slowly on its broad foot, or base.

The average height for an anemone is 18 to 29 centimeters. The largest is more than 35 centimeters tall and twice as wide. It lives in the warm waters of the Great Barrier Reef off the coast of Australia.

Some corals, like the sea anemones, have leathery skin. However, these corals have no stinging cells for protection. The corals protect their bodies by surrounding themselves with a rocklike substance. This substance is formed at the base, or foot, of the coral. It can protect itself by pulling into this house.

Each coral cements its house to its neighbor's. Over a long time, these rocklike houses form a coral reef. It takes millions of corals to make a reef.

Coral reefs are found close to islands in warm south seas. Most coral can't grow in water deeper than 45 meters or colder than 20* C. Therefore, most of it is found close to islands where the water is warm and not too deep.

During the day most of the corals stay hidden in their rock houses. At night they spread their tentacles to feed. As their soft bodies sway with the ocean currents, it looks to a diver like the whole reef has blossomed.

A reef built up by coral soon becomes a home for many other kinds of animals. The reef is usually filled with caves, nooks, and crannies. Fish, shellfish, and others hide in there for protection.