CORAL FACES A BLEACH FUTURE - from DIVER Magazine

DATELINE: 30th November 2000

CORAL FACES A BLEACH FUTURE
New co-ordinated research by coral scientists has revealed the true extent of coral damage in the Indian Ocean following the widespread bleaching episode of 1998, writes Tim Ecott.
The Coral Reef Degradation in the Indian Ocean (CORDIO) report, which is supported by the World Bank, World Wide Fund for Nature and Scandinavian governments, clearly shows that between 50 and 95 per cent of hard corals in much of the region have died.
Dr Olof Linden, co-author of the report, says: "The most complex marine eco-system on the planet just tipped over and died while we watched." According to CORDIO, the Seychelles, Maldives, East Africa and the Chagos archipelago are among the hardest hit areas.
"For divers this is bad news," comments Dr John Turner of the School of Ocean Sciences at the University of Wales. "But for the coastal populations in these countries, it is even worse. Up to 80 per cent of their economy may depend on reef-based activities, not just dive tourism but fisheries, too."
More evidence of the perilous state of tropical reefs was present at the 9th International Coral Reef Symposium held in Bali, Indonesia. Delegates heard that Indonesia was losing 6 per cent of its reefs annually to pollution, dynamite and cyanide fishing. "Basically, if you want to see coral reefs you may have to do it in the next 20 years," says Ove Hoegh-Guldberg, author of one of the most comprehensive studies presented at Bali. "With the way coral reefs have died in the past two years, marine scientists have been taken by surprise. The CORDIO report is evidence that global warming is affecting sea temperatures much faster than originally predicted."
While conservative estimates put rising temperature predictions at just 1°C this century, new models say parts of the Pacific may see a 5Ą rise, with 2-3Ą common in many parts of the tropics. An increase of just 1°C over a period of weeks is enough to bleach and kill most hard corals.
The long-term effects of coral death cannot be predicted but already there is evidence that many fish populations close to shore are declining. They rely on the reef structure for hiding places and for spawning nurseries.