FORT LAUDERDALE, Fla. (NEWSnet/AP) — Some Florida Keys coral reefs are losing their color weeks earlier than normal because of record-high water temperature.

Known as “bleaching,” it means reefs are under stress and their health is potentially endangered, federal scientists said.

Corals should be vibrant this time of year, but are going white swiftly, said Katey Lesneski, research and monitoring coordinator for Mission: Iconic Reefs, which U.S. National Oceanic and Atmospheric Administration launched to protect Florida coral reefs.

“The corals are pale, it looks like the color’s draining out,” said Lesneski, who has spent several days on the reefs during the past two weeks. “Some individuals are stark white. And we still have more to come.”

Surface temperature has averaged about 91 degrees, well above the normal mid-July average of 85 degrees, said Jacqueline De La Cour, operations manager for NOAA’s Coral Reef Watch program.

Coral reefs are composed of tiny organisms that link. The reefs get their color from the algae that live inside them and are the corals’ food. When temperature gets too high, the coral expels the algae, making the reefs appear white or bleached. That doesn’t mean they are dead, but the corals can starve and are more susceptible to disease.

Andrew Bruckner, research coordinator at the Florida Keys National Marine Sanctuary, said some coral reefs began showing the first signs of bleaching two weeks ago. Within the past few days, some reefs lost all their color. It’s that first time that has occurred prior to Aug. 1.

The peak for bleaching typically happens in late August or September.

Coral reefs are a natural buffer against surge from hurricanes and other storms. There can be economic impact from early bleaching, since tourism from fishing, scuba diving and snorkeling is dependent on reefs.

A 20-year, large-scale effort is underway to rebuild Florida's coral back to about 90% of what it was 50 years ago. Bruckner said scientists are breeding coral that are able to withstand the heat and using shade-covers and underwater fans to cool the water to help coral survive.

“We are looking for answers and we are trying to do something, rather than just looking away,” Bruckner said.

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