Post-bleaching benthic status on reef sites of Mandapam group of islands and Palk Bay, Indian Ocean following the 2016 bleaching events

Global bleaching event of 2016 has caused large scale degradation of coral communities at many reef systems. It is inevitable to understand the post bleaching community changes in the benthic system to estimate the recovery and resilience potential of the reef system. Here, we investigated the response of the benthic communities to the bleaching events across the selected reef sites of Mandapam group of islands and Palk Bay reef sites at May 2017, one year post-bleaching. Benthic surveys were conducted during the March–May months of 2016 (bleaching period) and May 2017 (post bleaching). Bleaching was evident in all surveyed reef sites along Mandapam group of islands and Palk Bay during 2016 with the maximum bleaching of 43 ± 2% in Poomarichan island coinciding with the maximum positive SST anomaly recorded in April 2016. Post bleaching survey revealed reduction of live coral cover followed with an increase in macroalgae cover. Maximum reduction of live coral cover was observed from Olakuda reef site (-2%), while maximum macroalgae outgrowth was observed from Kurusadai island (2.75%). Our results show reduced recovery capability of coral communities in Mandapam group of islands and necessitate the need for continuous observations to assess the recovery capability of corals of this region.