The BIG PICTURE: Electric Reefs

Text and Photograph by Brandon Cole

It sounds like a marine Frankenstein project: Graft coral onto a rebar skeleton, shock it and, “It’s alive!”

With reefs besieged on all fronts, the Global Coral Reef Alliance is taking charge. Literally. Their Biorock™ ‘reefs’ – metal constructs of various shapes, even a giant turtle – are growing corals and restoring degraded coastal reef habitats in 20 countries. This one is in Indonesia, in Permuteran Bay on Bali’s northwest shore.

Wired to onshore solar panels, windmills or already existing sources of electricity, low-voltage direct current flows through the structure, causing minerals in seawater to precipitate onto the steel frame and form a limestone layer. Scientists then attach small sprigs of salvaged coral, which quickly become cemented into place by the accumulating limestone. These transplants grow two to six times faster than normal, and wild coral larvae drifting by happily settle down and sprout with vigor.

Amped up Biorock corals can better cope with environmental stresses including pollution, sedimentation and climate change. In 1998’s catastrophic El Nino bleaching event, 50 to 80 per cent of corals on Maldivian electric reefs survived dramatically elevated water temperatures, as opposed to just five  to 10 per cent on adjacent off-grid reefs.

Biorock technology presents an effective opportunity not only to jumpstart coral restoration projects, but also to create vital habitat, build fish populations and support local communities through enhanced diving and snorkeling ecotourism. It even helps prevent beach erosion. See www.globalcoral.org