Pie charts of coral cover on Chagos reefs, showing the massive reduction after the 1998 mortality.  Blue is various groups of corals, red is calcareous algal cover in shallow water (the algal ridge and spur section), mauve is soft corals and other hydrozoans.  Uncoloured segments are dead or bare space.  Top is before the 1998 bleaching event, bottom two are seaward and lagoonal reefs after it.
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