Coral reef A fringing reef forms around an extinct volcanic island as the island and ocean floor subsides. As the subsidence continues, the fringing reef becomes a barrier reef and ultimately an atoll reef. Darwin predicted that underneath each lagoon would be a bedrock base, the remains of the original volcano. Subsequent research supported this hypothesis. Darwin's theory followed from his understanding that coral polyps thrive in the tropics where the water is agitated, but can only live within a limited depth range, starting just below low tide. Where the level of the underlying earth allows, the corals grow around the coast
Coral reef According to the Caribbean Coral Reefs - Status Report 19702-2012, states that; stop overfishing especially fishes key to coral reef like parrotfish, coastal zone management that reduce human pressure on reef, (for example restricting coastal settlement, development and tourism) and control pollution specially sewage, may reduce coral decline or even reverse it. The report shows that healthier reefs in the Caribbean are those with large populations of parrotfish in countries that protect these key fishes and sea urchins, banning fish trapping and spearfishing, creating "resilient reefs". To help combat ocean acidification, some laws are in place to reduce greenhouse gases