Just two decades ago, coral coverage in the Caribbean was commonly 40 to 60 percent. Scientists blame many factors disease, overfishing, pollution, excessive nutrients and global climate change for the rapid decline, which has also been seen to differing degrees among coral reefs worldwide.
"Some people would argue that coral reefs really don't exist as functional ecosystems in the Caribbean anymore," Hay said. "The best reefs we have today are poor cousins to what was only average 20 years ago."
For the future, Hay would like to expand the experiments to study the effects of additional species, and repeat the studies in different areas, such as the Fiji Islands, where residents are concerned about sustainability of the coral reefs. Though dependent on local fish for their protein, he said the Fiji Islanders may be able to change their fishing habits if researchers can determine which fish must be protected to help the reefs.
"The data we are seeing in Fiji suggests that diversity may be even more important there than it was in the Caribbean," he said. "There are a lot of different species doing a lot of very different things. These consumers are very important, and in areas where they are over-fished, the reefs are crashing."
The study provides more proof of how important biodiversity can be to maintaining healthy ecosystems.
"Species diversity is critically important, but we are losing critical components of the Earth's ecosystem at an alarming rate," Hay said. "There has been little work on the role of
|Contact: John Toon|
Georgia Institute of Technology Research News