Indonesia has long been famed for its exceptionally beautiful coral reefs. The island nation has the greatest area of coral reefs of any country in the world and those reefs contain the greatest diversity of reef species.
But since the late 1990s, the islands' underwater beauty has suffered from cyanide fishing and higher water temperatures. The effects were particularly evident during 1998's especially strong El Niño, which heated the eastern Pacific ocean water, killing once-flourishing reefs and exposing their bleached skeletons, similar to what is shown below:
But now, a diver on Bali has revived the reefs on this popular Indonesian island using Biorock technology pioneered by German architect and marine scientist Wolf Hilbertz in the 1970s. The Biorock process places metallic cages running with a weak, harmless electric current on the sea floor. There, the current reacts with the seawater, causing a buildup of limestone, a necessary ingredient to the growth of coral reef skeleton.
Bali's Pemuteran bay now has about 60 Biorock cages across two hectares, and the reef is flourishing more than ever.
Biorock, which has been found to make the corals more resistant against bleaching and global warming, is also being used to build corals in the Maldives, Seychelles, Thailand, Papua New Guinea, Mexico, Panama and the Saya de Malha Banks in the Indian Ocean.
Watch these two videos about Biorock below. The first is a short clip showing what the revived reef in Bali looks like:
The second video, Corals of Trawangan, is a 20-minute educational film, well worth the time. It describes efforts to rebuild reefs using Biorock technology on the tiny Indonesian island of Gili Trawangan, just off the western coast of Bali's neighboring island, Lombok. You can jump to the description of how they make and install the Biorock cages, which can be any shape or size, at 7 minutes in.