Electricity Revives Bali Coral Reefs

Joseph Coleman in Pemuteran Bay, Indonesia
Associated Press
December 4, 2007
Just a few years ago, the lush coral reefs off Indonesia's 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 the growth.

(See photos and video.)

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 Bay reefs off Bali's northwestern shore were under serious assault by 1998, victims of rising temperatures and impoverished islanders' aggressive fishing methods, which included stunning fish with cyanide poison and scooping them up with nets.

"Under these conditions, traditional (revival) methods fail," explained Goreau, who is 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.

How It Works

It has long been known that coral that breaks off the reef can be salvaged and restored if it can somehow be reattached.

Goreau's Bali project constructs metal frames, often in the shape of domes or greenhouses, and submerges 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 the pieces of live coral to the structure.

Goreau and his supporters say the electricity spurs the weakened coral to restore itself.

"When they get the juice, they are not as stressed," said Rani Morrow-Wuigk, an Australian-German who rents bungalows on the beach and has supported efforts to save the reefs for years.

Indeed the corals on the structures appear vibrant, and supporters say they have rebounded with impressive vigor. The coral in Pemuteran teems with clownfish, damselfish, and other colorful tropical animals.

(Related story: Damselfish Study May Help Improve Marine Reserves [October 13, 2004])

Money and Maintenance

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 program 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 long struggled to drive 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 more 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 Australia's capital Canberra to establish the Reef Gardeners of Pemuteran, an organization that 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."

Copyright 2007 The Associated Press. All rights reserved. This material may not be published, broadcast, rewritten, or redistributed.

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