Keys News
Friday, January 29, 2010

Coral bleaching is a condition often associated with the summer doldrums, but extreme cold weather, like what the Florida Keys experienced earlier this month, also can cause coral to bleach and die.

This month’s cold snap has the Florida Keys National Marine Sanctuary and other coral conservation groups conducting a survey to determine the extent of the damage. During the next two weeks, teams of scientific divers from federal and state agencies and nongovernmental and academic organizations will be surveying coral colonies from the Dry Tortugas through Martin County to assess coral reef health.

Temperatures in some Keys nearshore waters dropped to 52 degrees for several days — well below average for this time of year — with fatal results for some corals.

Mote Marine Laboratory BleachWatch Coordinator Cory Walter was surprised at the extent of the affected corals when she dove various patch reefs in the Keys last week. Most of the bleaching and death occurred in the mid-Hawk Channel and nearshore reefs, Walter said. The offshore reefs fared better. The cold seems to have affected all species equally, Walter said.

The coordinated and comprehensive assessment from the scientific community was sparked by initial reports from divers, Walter and The Nature Conservancy marine biologist Meaghen Johnson.

“If there is any good news, it’s that reef managers and scientists are able to quickly respond to this event and are in a good position to learn more about how reefs will rebound following such a rare occurrence,” said Chris Bergh, director of The Nature Conservancy’s Coastal and Marine Resilience Program.

Full story here.