Coral bleaching in the gulf of Thailand: Significant natural disturbance

It has been over a decade since the extensive coral bleaching (whitening of corals due to loss of symbiotic algae and/or their pigments) was first reported. This study describes the first extensive coral bleaching in the Gulf of Thailand. Field observations in coral communities of Chon Buri, Prachuab Khirikhan, Chumporn and Surat Thani Provinces were carried out during April-June, 1998. The results obviously show the patchiness in spatial occurrence of coral bleaching. The observed corals exhibited a variety degree of bleaching. Bleaching of coral recruits was also observed at many sites. The coral bleaching has been attributed to elevated sea temperature, solar radiation and a combination of both factors. There is a trend of increased frequency and intensity of coral bleaching in the Gulf of Thailand. Adaptation of corals and the interaction of anthropogenic and natural influences will be the important factors determining recovery of coral reefs from bleaching phenomenon.