Status of Maldivian reefs eight years after the 1998 coral mass mortality

Abstract

Episodes of coral bleaching and mortality have occurred with increasing frequency over the past two decades, often followed by proliferation of non-constructional organisms leading to a ‘phase shift’ in reef ecosystems. As the Maldives were severely affected by the 1998 episode, concern raised about the possibility of a phase shift there. The status of Maldivian reefs was surveyed eight years after the mass mortality of 1998; the percentages of biotic and abiotic benthic categories were estimated in both lagoon and ocean reefs. Hard coral cover did not exceed 37%, but no threat was recognized of a phase shift toward the dominance of soft corals, algae or sponges (7% on average). The high percentage of bare coral rock (up to almost 50%) and the local variability of living benthic cover suggest that Maldivian reefs were still in a re-colonization phase. Monitoring of their evolution is in progress.

Keywords:

• coral reefs
• benthic categories
• phase shift
• Maldives

Acknowledgements

Albatros Top Boat (Verbania and Malé) organized our scientific cruise in the Maldives: we especially thank Donatella ‘Dodi’ Telli and Massimo Sandrini for their support. Thanks are also due to Paolo Colantoni (Urbino), for the many useful suggestions, and to Romina Rivella (Genova), for help during field activities.