April Feature: Coral Reefs Healthy coral reefs teem with life - 25 per cent of all marine species live among corals, making them the world's most biologically diverse marine ecosystem. Turtles and seabirds feed on the wide variety of animals and plants, such as fish, crabs, worms, sponges, and molluscs. Reefs are formed by the skeletons of coral polyps - small animals with sack¡like stomachs, mouths, and stinging tentacles. They spend most daylight hours sitting inside their crusty, cup¡shaped, limestone skeletons, and come out at night to feed. As they grow, most polyps subdivide to form complex colonies made up of millions of polyps, fused together by their skeletons. Coral reefs develop at different rates: "branching" corals can grow as much as 15cm per year, while moundlike "massive" corals expand at an annual rate of 0.5-2.5cm. Learn MORE About Coral Reefs... Coral Reefs Fact Sheet

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