It is then that they feed, catching drifting plankton in their outstretched tentacles. These primitive, unassuming animals are the mighty master builders of the reefs. The creation of one reef requires the team efforts of billions of individuals. Together, hundreds of these skeletons make a coral. Many corals, growing side by side and one on top of the other, form a reef.
Corals are very particular about where they build reefs.
Such conditions exist all along the Florida Keys in and south of Biscayne and in the Caribbean, as well as in some other tropical oceans. The reefs are the cities of the sea. In and around them lives a huge and diverse population of fish and other marine creatures. Every hole, every crack is a home for something. Some inhabitants, like the Christmas tree worm, even live anchored to the coral.