’Geology’ September 05 cover story: Coral reef decline – not just overfishing

Coral reefs, the rainforests of the sea, feed a large portion of the world’s population, protect tropical shorelines from erosion, and harbor animals and plants with great potential to provide new therapeutic drugs. Unfortunately, reefs are now beset by problems ranging from local pollution and overfishing to outbreaks of coral disease and global warming. Although most scientists agree that reefs are in desperate trouble, they disagree strongly over the timing and causes of the coral reef crisis. This is not just an academic exercise, because different answers dictate different strategies for managers and policymakers intent on saving reef ecosystems. The cover story published this month in Geology helps focus the debate.

A team led by Richard Aronson of the Dauphin Island Sea Lab in Alabama took cores through reef frameworks in Belize to reconstruct the history of the reefs over the past several thousand years. Although some scientists have suggested that reefs began their decline centuries ago due to early overfishing, Aronson’s team found that coral populations were healthy and vibrant until the 1980s, when they were killed by disease and high sea temperatures. The research effort was supported by the National Geographic Society, the Smithsonian Institution and the National Science Foundation.

As Aronson points out, “Protecting fish populations is important in its own right, but it won’t save the corals. Corals are being killed at an unprecedented rate by forces outside local control. Saving coral reefs means addressing global environmental issues–climate change in particular–at the highest levels of government.”