The preliminary result of  survey that conducted by WCS has found that most of the bleached corals reported in found in May and June, are dead, only one month after. This is one possibly of the most rapid and widespread events of coral mortality that has been recorded in Indonesia. It is a total genocide of the Aceh coral reefs that have shown speatacular recovery in the aftermath of reduced destructive fishing activity following the tsunami.

Acropora are the most affected species where up to 80% have died. Some species of Faviidae (e.g. Favia, Favites, Platygyra) are still bleached, with most of them are expected die within next few weeks.

The sea surface temperature anomaly that occurred in the Andaman Sea from May to June 2010 has lead to a mass coral bleaching throughout the region, from Bangladesh, Thailand, Andaman and Nicobar, down to the Northern Aceh region.  According to the NOAA’s Coral Reef Watch website, the high sea surface temperature reached its peak on the end of May 2010, where the temperature reached 4o Celsius higher than normal (34o C).  As soon as the coral bleaching was reported in Aceh, the Wildlife Conservation Society Indonesia Program sent a “rapid response unit” to the field to measure the magnitude of this event.  From the first response survey in May-June 2010, WCS found that up to 60% of corals in Northern Aceh were bleached.

This week WCS set up a fine survey of the mortality of corals has included marine ecologists from the Wildlife Conservation Society, James Cook University, and Syiah Kuala University to assess the progress of the bleaching event in Northern Aceh.  The survey started on July 26th and continues until August 3rd.

The 2010 coral bleaching event is far worse than what people and the scientific team had expected. One of the possible reasons why Aceh has been so devastated in that corals in the area are rarely subject to the variations in sea surface temperature recorded this year – so were unable to adapt or indeed are not adapted to such variations. Our story written a few weeks ago shows that reports of bleaching at several regions in Indonesia (e.g. Bali, Lombok, Wakatobi, and North Sulawesi) where the Reef Check Indonesia team is now conducting surveys.  Result from the Aceh surveys can and should become basis for reef managers in this region to take more action to improving the management of coral reefs.

Yudi Herdiana

Wildlife Conservation Society

Indonesia Program