Fringing reefs consist of several zones that are characterized by their depth, the structure of the reef, and its plant and animal communities. Barrier Reef - Barrier reefs are reefs that are separated from land by a lagoon. These reefs grow parallel to the coast and are large and continuous. These features are followed by another coral terrace and a vertical drop into deeper waters. Atoll - Atolls are annular reefs that develop at or near the surface of the sea when islands that are surrounded by reefs subside.
Atolls separate a central lagoon and are circular or sub-circular.
Coral Feeding Corals can obtain food in a variety of ways. Reef-building corals rely on the photosynthetic products of zooxanthellae for the majority of their nutrients. However, corals also capture zooplankton for food. Corals are suspension feeders. Nematocysts on the tentacles and mesentarial filaments can be used to sting prey and move it into the mouth.