August 19, 2010

Coral Reefs Dying At Alarming Rate In Indonesia

Rising ocean temperatures in waters off the northwestern coast of Indonesia are killing off coral at one of the fastest rates ever recorded, conservationists warned Wednesday, adding that the threat extends to other Asian reefs as well.

The Wildlife Conservation Society sent biologists to Aceh province, on the tip of Sumatra Island, in May when waters in the Andaman Sea peaked at 93 degrees Fahrenheit -- a 7 degree rise over long-term averages.

The biologists found that the coral was suffering from massive bleaching, which occurs when algae living inside coral tissues are expelled. Surveys that have been carried out since the finding, with Australia's James Cook University and Indonesia's Syiah Kuala University, have found that 80 percent of those corals have died.

The scientists said the speed and extent of mortality appears to exceed that of other bleaching events in recent history. The apparent cause appears to be warming seas, which can be blamed, at least partly, on global warming.

Many coral formations were severely damaged by El Nino-linked warming in 1997 and 1998. They were rebounding when they were struck another blow when a 2004 earthquake triggered a tsunami that damaged more than a third of Aceh's reefs. However, scientists said the reefs recovered faster than expected, thanks in part to natural colonization and a drop in illegal fishing.

"It's a disappointing development, particularly in light of the fact that these same corals proved resilient to other disruptions to this ecosystem," Stuart Campbell of the Wildlife Conservation Society wrote on their website.

"It is an unfortunate reminder that international efforts to curb the causes and effects of climate change must be made if these sensitive ecosystems and the vulnerable human communities ... that depend on them are to adapt and endure," he wrote.

The National Oceanic and Atmospheric Administration's (NOAA) website indicates that the entire Andaman Sea is being affected by the high water temperatures. Higher sea temperatures were also occurring when the sun was at its zenith and at times when there are little cloud cover.

Clive Wilkinson, a coordinator at the Global Coral Reef Monitoring Network in Australia, called it a "lethal combination" for coral, especially when it continues for more than a month, as was also the case in 1998.

Rising sea temperatures have affected reefs across Indonesia as well as in Malaysia, Thailand, Vietnam and Sri Lanka, and the hotspots are now pushing northward.

"This is really quite serious," said Wilkinson. There is a major heating period and its breaking all records. "There are very furious worries now about the Philippines and eventually Taiwan and probably southern Japan" being affected by these conditions, he added.


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