Recent Coral Bleaching Impacts in Reef Ecosystem of Gulf of Mannar and Palk Bay

KOUSHIK SADHUKHAN, Ramesh Chatragada, Shanmugaraj T, Ramana Murthy M V


Coral bleaching now becomes an annual phenomenon in Gulf of Mannar (GoM) and Palk Bay (PB). In 2019 and 2020, reefs are completely bleached by the effect of high sea surface temperature which not only impinge on the reef building corals but also triggers the growth of unwanted macroalgae in live reefs. The consequences of this major threats are long term and fatal to the marine ecosystem. Recurrence of bleaching in 2020 was documented on the same month (April, 2020) as it was appeared in last year April, 2019. The increasing heat in the summer is the main cause of this bleaching. Moreover, it is a negative environmental response by reef building corals which slowly recovered after the temperature fell down. Present study doesn’t report any mass mortality of corals and other organisms due to bleaching but this state facilitate the growth of macroalgae on corals which have fatal impact near after. Line intercept transect (LIT) and quadarat sampling method was employed in triplicate to the six location of Gulf of Mannar (GoM) and Palk bay (PB) regions to estimate the intensity of bleaching and compare the data with last year bleaching event. Present study infer that no significant bleaching differences observed on the reef building corals but habitat degradation is clearly visible based on field observation. Post bleaching impacts needs to be lowered by implementing alternate management intervention programme to maintain the reef resilience in GoM and PB regions.


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