A snapshot of reef conditions in North Ari Atoll (Maldives) following the 2016 bleaching event and Acanthaster planci outbreak

Abstract

Coral reefs are degrading worldwide. This study explored the benthic community structure (biotic and abiotic benthic cover and coral composition) at three islands (Rasdhoo, Maayafushi and Vihamaafaru) in the central Maldivian archipelago, 2 years after the 2016 El Nino–Southern Oscillation (ENSO) and the associated mass-bleaching events. Hence, we assessed benthic cover on the same GPS sites and depth (10m) of a subset of reefs that had been previously studied. The islands represent a range of management categories and oceanic influence. Average live coral cover in 2018 was lowest on Maayafushi reefs (0.65±0.41%), a resort island with minimal exposure to oceanic influence. At Rasdhoo, a community island with south-eastern oceanic exposure, live coral cover was 14.70±3.20% and 90% of the colonies were less than 20cm in diameter. At Vihamaafaru, an uninhabited island with oceanic exposure from the west, reefs assessed had a live coral cover of 17.9±6.80%, Acropora spp. remained the dominant taxa, and 35% of colonies were 20cm or greater in diameter. This evident trend, in variation of live coral cover and size of the coral colonies, among the three island settings indicates the greatest potential for recovery of coral cover on reefs with more exposure to oceanic influence.