Caribbean coral reefs in danger from coral bleaching

UPI 8 Oct 10;

WASHINGTON, Oct. 8 (UPI) -- Coral reefs in the Caribbean are in danger of bleaching, researchers say.

Scientists attribute the bleaching, caused by high water temperatures, to global climate change.

Mark Eakin, coordinator of Coral Reef Watch at the U.S. National Oceanographic and Atmospheric Administration, said coral bleaching is hitting more areas and some corals in the Caribbean that were spared in 2005, a year in which ocean temperatures were extremely warm, The New York Times reports.

"I've heard of lots of bleaching and lots of dead corals in Panama," Eakin told the Times. "The bleaching is really kicking in strong at this point."

Bleaching occurs when high heat and sunshine cause the coral to "spit out" the algae that live symbiotically inside them. Severe bleaching can lead to coral death.

A study released this week by the University of Buffalo in New York indicates that certain types of coral won't be able to adapt rapidly enough to survive global warming. The University of Buffalo researchers studied Porites divaricata, a common shallow-water scleractinian coral found throughout the Caribbean.

While coral reefs -- known as the rain forests of the sea for their biological richness -- account for 1 percent of the world's ocean surface, they provide a home for 25 percent of all sea life. The demise of coral reefs would deprive fish of food and shelter, severely threatening reef fish populations and marine diversity.

The area affected by bleaching and dying corals would likely extend to the region east of Nicaragua, past Haiti and the Dominican Republic to Puerto Rico and the Lesser Antilles, and south along the Caribbean coasts of Panama and South America, a warning issued in August by Coral Reef Watch stated.

Water temperatures in the Caribbean reach their annual peak in September and October.

"There is the potential that this will be worse than 2005, unless some tropical storms come through and mix the warm surface water with deeper, cooler water," Eakin told Inter Press Service. That year, a severe bleaching occurred across much of the Caribbean and more than 60 percent of the coral around the U.S. Virgin Islands died.

Widespread coral bleaching has already occurred this year in Southeast Asia and the western Pacific.

Mary Alice Coffroth, professor of geological sciences at the University of Buffalo, warned that most estimates predict that by 2100, global warming would cause sea temperatures to rise by as much as 2 to 6 degrees Celsius more than current temperatures.