One-Quarter of World's Coral Reefs Destroyed

ByABC News
October 23, 2000, 10:02 AM

N U S A  D U A,  Indonesia, Oct. 23 -- More than a quarter of the worldscoral reefs have been destroyed by pollution and global warming andunless drastic measures are taken, most of the remaining reefs maybe dead in 20 years, scientists said today.

In some of the worst-hit areas, such as the Maldives andSeychelles islands in the Indian Ocean, up to 90 percent of coralreefs have been killed over the past two years by an increase inwater temperature.

You have to go and look at the coral reefs now, as we arelosing them, said Clive Wilkinson, a leading Australianscientist.

Pockets of Ecosystems

Coral reefs, the rain forests of the sea, play a crucialrole in the oceans as an anchor for most marine ecosystems. Theirloss would place thousands of species of fish and other marine lifeat risk of extinction.

Researchers told the 1,500 delegates from 52 countries attendingthe 9th International Coral Reef Symposium on Indonesias touristisland of Bali that governments must wake up and urgentlyreverse global warming trends, cut pollution and crack down onover-fishing.

In some areas fishermen use dynamite or cyanide to catch fish,blowing the reefs apart or poisoning them, Wilkinson said. In otherareas, governments are pumping untreated sewage and other poisonouswaste directly into oceans.

But the scientists emphasized that the most serious andimmediate threat to the worlds reefs is global warming, which iscausing a damaging condition known as coral bleaching.

Warming Waters

The term describes a condition where higher water temperaturesheat the coral, which becomes stressed and expels the microscopicplants that give it its vibrant color. If the coral is not cooled,it dies.

Oceanographers say that the El Niño weather pattern two yearsago, which led to a rise in water temperatures by up to 6 degrees Fahrenheit, did enormous damage to the coral reefs, some of which had been alive for up to 2.5 million years.