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Just a few years ago, the lush coral reefs off Bali island were dying out, bleached by rising temperatures, blasted by dynamite fishing and poisoned by cyanide.
Now they are coming back, thanks to an unlikely remedy: electricity.
The coral is thriving on dozens of metal structures submerged in the bay and fed by cables that send low-voltage electricity, which conservationists say is reviving it and spurring greater growth.
As thousands of delegates, experts and activists debate climate at a conference that opened this week on Bali, the coral restoration project illustrates the creative ways scientists are trying to fight the ill effects of global warming.
The project - dubbed Bio-Rock - is the brainchild of scientist Thomas Goreau and the late architect Wolf Hilbertz. The two have set up similar structures in some 20 countries, but the Bali experiment is the most extensive.
Goreau said the Pemuteran reefs off Bali's northwestern shore were under serious assault by 1998, victims of rising temperatures and aggressive fishing methods by impoverished islanders.
"Under these conditions, traditional [revival] methods fail," explained Goreau, who was in Bali presenting his research at the UN-led conference. "Our method is the only one that speeds coral growth."
Some say the effort is severely limited.
Rod Salm, coral reef specialist with the Nature Conservancy, said while the method may be useful in bringing small areas of damaged coral back to life, it has very limited application in vast areas that need protection.
"The extent of bleaching ... is just too big," Salm said.
"The scale is enormous and the cost is prohibitive."
Others note the Bali project is mostly dependent on traditionally generated electricity, a method that itself contributes to global warming. Goreau himself concedes it has yet to attract significant financial backing.
Nonetheless, scientists agree that coral reefs are an especially valuable - and sensitive - global environmental asset. They provide shorelines with protection from tides and waves, and host a stunning diversity of plant and sea life.
Goreau's method for reviving coral is decidedly low-tech, if somewhat unorthodox.
It has long been known that coral that breaks off the reef can be salvaged and restored if it can somehow be reattached.
What Goreau's Bali project has done is to construct metal frames, often in the shape of domes or greenhouses, and submerge them in the bay. When hooked up to a low-voltage energy source on the shore, limestone - a building block of reefs - naturally gathers on the metal. Workers then salvage coral that has broken from damaged reefs and affix it to the structure. Goreau and his supporters say the electricity spurs the coral to revival and greater growth.
"When they get the juice, they are not as stressed," said Rani Morrow-Wuigk, an Australian-German woman who rents bungalows on the beach and has supported efforts to save the reefs for years.
And indeed, the coral on the structures appears vibrant. Supporters say they have rebounded with impressive vigour. The coral in Pemuteran teems with clownfish, damselfish and other colourful tropical animals.
Funding, however, is a major problem. There are some 40 metal structures growing coral in Pemuteran Bay and about 100 cables laid to feed them with electricity, but only about a third of the wires are working because of maintenance problems and the cost of running them, said Morrow-Wuigk.
The electrification programme is part of a wider effort in the bay to save the coral.
Chris Brown, an Australian diving instructor who has lived in Bali for 17 years, said he and other people determined to save the reefs have had a long struggle driving away fishermen who use dynamite and other coral-destroying methods to maintain their livelihoods.
He said a key has been demonstrating to shoreline communities the benefits of coral reef maintenance, such as growing fish stocks and jobs catering to tourists who come to dive in the area.
Brown has participated in Goreau's projects, and won funding from the Australian Government to set up a Bio-Rock structure electrified by solar panels fixed on a floating offshore platform.
Brown has also used seed money from Canberra to establish the Reef Gardeners of Pemuteran, which trains islanders to dive, maintain the solar-paneled coral structure and clean the reefs of harmful animals.
Kadek Darma, 25, a Balinese who has worked with Brown for two years, said the advantages of the corals to the local economy were obvious.
"They attract the tourists, and more tourists means more jobs," he said. "I hope we can all keep maintaining the reefs for our great-great grandchildren."
* RESCUE REMEDY
Low voltage electricity has been used to save the coral reefs off Bali.
Metal frames are constructed and hooked up to a low-voltage energy source on the shore.
Coral that has broken off is affixed to the structure.
Electricity helps the weakened coral to grow.
- AP