A 2005 earthquake off the coast of Indonesia pushed an island 1.2m out of the water, causing one of the biggest cases of coral deaths recorded, scientists said yesterday.
Researchers surveying the island of Simeulue in March found that most corals along its 300km perimeter had been partly raised out of the water by the 2005 earthquake, with the exposed parts dying off. It is believed to be the first time that scientist have documented the impacts on corals from a quake.
"The scale of it [the impact] was quite extraordinary," said Andrew Baird, of the Australian Research Council Centre of Excellence for Coral Reef, who took part in the survey with scientists from the Wildlife Conservation Society.
"Exposed corals were everywhere," he said.
Baird, who said their findings would be published later this year, said exposed corals stretched from a few meters from shore to as far as 500m.
"Some species suffered up to 100 percent loss at some sites, and different species now dominate the shallow reef," he said.
More than 900 people were killed and tens of thousands left homeless in the 8.7 magnitude earthquake that hit Nias, Banyak and Simeulue islands off the coast of Sumatra.
Australian reef expert Clive Wilkinson, who did not take part in the survey, said the damage to the reefs on Simeuleu was to be expected.
"I don't think it's anything new. This has been going on for millions of years," Wilkinson said. "It's part of natural reef evolution. There are many islands in the Pacific that are actually uplifted coral reefs. It's just what happens to reefs."
"The news from Simeulue is not all bad," Stuart Campbell, coordinator of the Wildlife Conservation Society's Indonesia Marine Program, said in a statement.
"At many sites, the worst affected species are beginning to re-colonize the shallow reef areas," he said. "The reefs appear to be returning to what they looked like before the earthquake, although the process may take many years."
Baird said their findings should give hope to communities in the Solomon Islands, where concerns have been raised that an April 2 earthquake and tsunami might have damaged its reef ecosystem and in turn its diving industry.
"They shouldn't be worried about losing their dive industry," Baird said of the Solomon Islands.
"Everything still in the water will still be fine," he said.