‘Unprecedented die-off’ of Caribbean coral

Hot spring, summer
For the Caribbean, it all started with hot sea temperatures, first in Panama in the spring and early summer, and it got worse from there.

New NOAA sea surface temperature figures show the sustained heating in the Caribbean last summer and fall was by far the worst in 21 years of satellite monitoring, Eakin said.

“The 2005 event is bigger than all the previous 20 years combined,” he said.

What happened in the Caribbean would be the equivalent of every city in the United States recording a record high temperature at the same time, Eakin said. And it remained hot for weeks, even months, stressing the coral.

The heat causes the symbiotic algae that provides food for the coral to die and turn white. That puts the coral in critical condition. If coral remains bleached for more than a week, the chance of death soars, according to NOAA scientists.

In the past, only some coral species would bleach during hot water spells and the problem would occur only at certain depths. But in 2005, bleaching struck far more of the region at all depths and in most species.

A February NOAA report calculates 96 percent of lettuce coral, 93 percent of the star coral and nearly 61 percent of the iconic brain coral in St. Croix had bleached. Much of the coral had started to recover from the bleaching last fall, but then the weakened colonies were struck by disease, some of it caused by human sewage, finishing them off.

Ability to adapt questioned
Eakin, who oversees the temperature study of the warmer water, said it’s hard to point to global warming for just one season’s high temperatures, but other scientists are convinced.

“This is probably a harbinger of things to come,” said John Rollino, the chief scientist for the Bahamian Reef Survey. “The coral bleaching is probably more a symptom of disease — the widespread global environmental degradation — that’s going on.”

Crabbe said evidence of global warming is overwhelming.

“The big problem for coral is the question of whether they can adapt sufficiently quickly to cope with climate change,” Crabbe said. “I think the evidence we have at the moment is: No, they can’t.

“It’ll not be the same ecosystem,” he said. “The fish will go away. The smaller predators will go away. The invertebrates will go away.”

MORE FROM ENVIRONMENT

Environment Section Front

Mystery of Florida's dying palms Shipping company charged in S.F. spill Oil shale under Rockies sparks battle Green cars in line for better batteries GM, utilities join to study electric car’s impact Solar-power pioneer circles back Designers add green touch to styling See these must-visit spots before it's too late Explorer to take 62,000-mile eco-trek EarthTalk Q&A: plug-in hybrids, green roofs Environment Section Front   Add Environment headlines to your news reader: