for National Geographic News Eight years after warming seas
caused the worst coral die-off on record, coral reefs in the
Indian Ocean are still unable to recover, biologists say. Many
reefs have been reduced to rubble, a collapse that has deprived
fish of food and shelter. As a result, fish diversity has
tumbled by half in some areas, say authors of the first long-
term study of the effects of warming-caused bleaching on coral
reefs and fish. The study focused on reefs near Africa's
Seychelles islands, north of Madagascar (see Seychelles map),
which sustained heavy losses from bleaching in 1998. "The
outlook for recovery is quite bleak for the Seychelles," said
lead study author Nicholas Graham, a tropical marine biologist
at England's University of Newcastle Upon Tyne. The study, in
today's Proceedings of the National Academy of Sciences,
predicts that isolated reef ecosystems like that around the
Seychelles will suffer the most from global warming-caused
bleaching events. Small but prolonged rises in sea tem