No reef relief - July 11, 2008
Earlier this week a report painted a bleak picture of the state of US coral reefs. Now a paper in Science has done the same thing for the rest of the world.
The paper’s title says it all really: ‘one-third of reef-building corals face elevated extinction risk from climate change and local impacts’.
Kent Carpenter and his colleagues applied international standards on classifying risk to species 845 corals. Of the 704 they could assign an IUCN category to, 33% are at risk of extinction. In case you hadn’t got the message the paper adds, “The proportion of corals threatened with extinction has increased dramatically in recent decades and exceeds most terrestrial groups.”
“The threshold for (corals) could be approached by the middle of this century ... when they'll reach a point where they may no longer be able to reproduce themselves as fast as they're being destroyed,” says Chris Langdon, of the University of Miami (Reuters).
More coverage
BBC (with video of coral bleaching)
The Virginian-Pilot (mini-profile of lead author Carpenter)
IUCN press release
Voice of America report
Image: Porites pukoensis listed as Critically Endangered / © Donald C. Potts
Comments
What is the average rise in ocean temperature in the vicinity of coral reefs over the last century or two? My guess is that it's not over a degree or two, and that seems way too little to be causing (or even contributing to) the coral reef problem. Coral reefs have been around for what, sixty million years? And endured much warmer climates than the present ones? My guess is that the problem is something else (over-fishing? pollution?). The danger with blaming it on global warming is that the real cause (assuming it is something else) will go un-fixed. Also, is there any evidence that reefs are growing faster further away from the equator than they used to? One would expect that they could, given that there's an obvious thermal gradient by latitude.
Posted by: Mike Maxwell | July 15, 2008 10:30 PM