The jewel in the world’s coral reef crown is threatened by devastating predatory starfish, according to conservation groups. Researchers found that Crown of Thorns starfish have “almost completely destroyed” some areas of reef at Halmahera in Indonesia, at the centre of the so-called Coral Triangle between Indonesia, the Philippines and Papua New Guinea (press release 1, news coverage in The Age, AFP, Reuters).

“The heart of the Coral Triangle is broken,” says Tasrif Katawijaya from the Wildlife Conservation Society (press release 2). Surveying of Halmahera was being conducted for the WCS and ARC Centre of Excellence for Coral Reef Studies.

Apparently the outbreak is likely caused by poor water quality. It could, warns the WCS, be an early sign of widespread decline in the reefs.

“The main cause of damage to the corals was the Crown of Thorns starfish. We witnessed a number of active outbreaks of this coral predator. There was little to suggest that the reefs have been much affected by climate change as yet: the threats appear far more localized,” says Andrew Baird, of the ARC centre of and James Cook University.

On his blog Rick MacPherson, program director for the Coral Reef Alliance, takes a longer look at the COTs (as the starfish are apparently known to conservationists) and what the new report adds. [Shameless plug: MacPherson is also on Nature Network.]

Image: crown of thorns starfish / Wildlife Conservation Society