With many of the coral reefs in the Caribbean ill from environmental factors, researchers believe the reefs could cease to exist in as few as two decades. The dying reefs have been the subject of a number of scientific studies which aim at determining the underlying causes of the rapid decline.

Pollution, global warming and overfishing are thought to have caused the reefs decay, but ia new study released by a number of nature conservancy groups -- The International Union of Nature Conservation, United Nations Environment Program and the Global Coral Reef Monitoring Network -- there may be a new answer to the equation. The study found that the underlying cause of destruction may be linked to populations of parrotfish and sea urchins being on the decline. 

The ocean is one giant ecosystem, and the coral reefs of the Caribbean depend on sea urchins and parrotfish because both of these species feed on seaweed.

Seaweed has its purposes in the ocean, but it is detrimental to the health of reefs due to its invasive nature. When seaweed blankets the coral, it acts as a blanket, smothering it and keeping it from feeding. If parrotfish and sea urchin populations fall, then there is no sea life to keep the seaweed from doing reef damage.

Jeremy Jackson, lead author of the research report says, "The situation is truly horrific in the sense that you have all these places that are desperately overfished."

Overfishing is a troublesome foe, as fishermen depend on the fish to make their living. 

Mark Eakin, coral reef watch coordinator with the National Oceanic and Atmospheric Administration thinks that the research report fails to recognize the true damage that ocean warming plays in the situation.

Eakin cites that there were six substantial bleaching events that also contributed to the decline of the reefs.

A rise in water temperature will also cause coral to eject the colorful algae that they house inside their tissue. 

Although the U.S. government has banned fishing of the blue, midnight and rainbow parrotfish, more has to be done if the coral reefs are to survive.

However, if Eatkin is right and global warming is the real cause, then it will be even more difficult to save the coral reefs of the Caribbean.