January freeze killed acres of Fla. coral

MIAMI, March 9 (UPI) -- A January chill in South Florida killed hundreds of acres of corals in the Florida Keys, scientists say.

The die-off was most severe between Biscayne Bay and Summerland Key, about 20 miles east of Key West, The Miami Herald reported. Offshore reefs suffered little, and corals north of Miami and in the Key West area and Dry Tortugas were also spared.

The survey, done for other reasons, was carried out by 31 scientists working for 31 organizations. James Byrne of the Nature Conservancy, who heads the Florida Reef Resilience Team, said the group found damage from cold was more severe than in 1977, the last time the region was hit with such low temperatures.

In recent years, scientists have been more concerned about warming water in the Caribbean. Temperatures of 88 degrees or more bleach coral, which becomes irreversible if the warmth lasts for more than a few days. Water temperatures below 60 degrees kill coral as well.

The Florida Keys National Marine Sanctuary has suspended scientific permits for collection of coral and is encouraging divers to head for artificial reefs and wrecks to try to give the coral reefs a chance to recover.