coral reef ecosystems

Coral reef ecosystems are marine environments built around reef-forming corals—colonies of tiny animals that secrete calcium carbonate skeletons.

These structures support extraordinary biodiversity, housing fish, invertebrates, and algae in complex interdependence.

Often called rainforests of the sea, coral reefs occupy less than one percent of ocean floor but shelter roughly a quarter of all marine species.

Climate change and ocean acidification threaten coral reef ecosystems worldwide.