Middle and South Andaman Islands have a fairly good fringing reef ecosystem, particularly the North Bay, Chidiyatappu, Ross and Havelock Islands. These reefs are dominated by Porites lutea, Porites nigrescens and Acropora spp. The appearance of corals or part of them in white (bleaching) is known to be associated with stress, which may be induced by sudden increase of sea-surface temperature (SST). 

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