GCRA is proud to present video and photographs of Biorock reefs taken by in October 2020 by Delphine Robbe of the Gili Eco Trust, showing Lombok reefs that had fully recovered around six months after bleaching. They illustrate the unique resilience of Biorock reefs to severe bleaching.

In 1998 Gili Trawangan reefs suffered catastrophic, near total, bleaching mortality. In the years that followed the Gili Eco Trust, partnering with the Global Coral Reef Alliance and Biorock Indonesia and local businesses and government, regenerated spectacular reef recovery with around 150 Biorock reefs. The entire economy of the island was based on the huge number of divers attracted to Gili Trawangan to dive on Biorock reefs full of spectacular corals and vast swarms of fishes. During the severe bleaching event of 2016 only the Biorock reefs survived. The same has happened again in 2020, illustrating clearly that Biorock is the only method known to protect coral reef ecosystems from catastrophic bleaching.

Delphine Robbe of the Gili Eco Trust who manages around 150 extraordinary Biorock reefs around the diving island Gili Trawangan, Lombok, whose economy is based almost entirely on diving tourism, reports that the economy has almost entirely collapsed and the reefs were hit by coral bleaching in 2020. She says:


“Here many businesses have closed and the main difference is that there are only a few people in the water and on the reefs every day. Noise and petrol pollution have stopped completely from the boats coming from Lombok or picking up guests or diving boat or snorkelling boats, therefore no anchor dropped on the reefs daily. Only one fast boat coming from Bali, 3 times a week, rather than 15 fast boat companies coming to Gili twice a day daily. Our anchor watch surveys will count up to 80 anchors dropped daily in 200m2 area, now it is down to 1 or 2 a day and most of the time ZERO!

Bleaching started here in January 2020 as in December 2019 we started to record high temperatures but then we got cold waters again in February and March. Most of the corals recovered quickly as it seemed to be a short bleaching event but then in April- May- June the temperature went up again. The bleaching was not too severe here.

Most of the Biorock reefs do not have electricity as the businesses are closed and not providing the electricity anymore. We only have about 3 power supplies still on at the moment”


The first three short videos show a set of Biorock reefs that were started before the 2016 bleaching event using a single species in order to compare growth under different conditions. These corals have not only grown so densely as to almost completely conceal the structure they grew over, they also have produced spectacular fish populations. These corals had complete recovery after the 2016 and 2020 mass bleaching events that devastated populations of the same species at sites away from the Biorock projects.



The 149 photos that follow are the October 2020 photographic transect of structures that Delphine has recorded repeatedly for years, allowing systematic comparison of coral growth and survival. The first structure shown is the very first Biorock structure built in Gili Trawangan, and then a series of many structures of different shapes, sizes, and depths. All are seen to have spectacular growth of corals and all reef organisms, which have survived repeated coral-killing bleaching events. There is now little coral left in the world like these Biorock Coral Arks to save coral reefs from global warming extinction.

Tourism in Gili Trawangan, which was almost entirely based on diving, much on the roughly 150 Biorock reefs around the island, has collapsed due to Covid, making many dive shops and hotels that were powering these structures close, and making it very difficult for the Gili Eco Trust to maintain many of these structures under power.

The Gili Eco Trust desperately needs your help to maintain this project in these dark times! Please support these crucial Biorock Coral Arks to maintain coral reef biodiversity in the Coral Triangle.”>You can make donations directly to the Gili Eco Trust here:

GCRA will pass on all donations, specifically earmarked to support Gili Trawangan projects directly to Gili Eco Trust. Donations to GCRA are US tax-deductible.