This project restores the degraded coral reefs on Nusa Penida Island in Bali, Indonesia. SeaTrees project partner, Ocean Gardener, employs local Balinese fishermen to restore the reef and monitor the regeneration until it can survive on its own.

In 2021, 6,000 fragments of coral were planted and in May 2022 we expanded the project to a new restoration site in Crystal Bay and are planting another 6,000 coral fragments. We also began the process of scientific monitoring using 3D mapping technology with Scripps Institute of Oceanography.

The conservation of these ecosystems is vital to coastal protection, scientific research, medication, fishing, eco-tourism, and more. Restoring these reefs will provide a habitat for more than 500 species of fish, many of which are currently considered vulnerable to extinction, and create 20 jobs for local villagers, supporting 12 families.

This is important because coral reefs are threatened globally. About half of the world’s coral reefs have been lost in the last 30 years. More than 60% of the remaining reefs are threatened by human activity, with Indonesia being one of the largest areas of vulnerability. Known as the “rainforests of the sea,” coral reefs are the largest living structures on earth and support 25% of marine life.

This coral restoration process begins with growing coral fragments in the shallow waters of the Ped Acropora Coral Nursery. These fragments grow and bond to biodegradable rope lines until they are large enough to be transplanted to the restoration sites on Nusa Penida Island at Ped and Crystal Bay. This innovative technique, adapted from a traditional Balinese method used to grow seaweed, ensures that the coral fragments will grow to be appropriately spaced and that the ecosystem will thrive in the years to come. 

Once the coral has been cultivated, a snorkeling team transplants the newly grown fragments onto the reef, slowly dropping them at the restoration site on the ocean floor and securing it in place. Divers prepare the restoration site by hammering stakes into the ground to allow for the rope lines to be secured in place on the reef without the fragments touching the ocean floor until they grow large enough to withstand the harsh “rubble” environment below.  Planting these fragments amongst healthy reefs will allow the ecosystem to thrive and help marine life return to the area.

Millions of people around the world also depend on fisheries, tourism and coastal protection provided by healthy coral reefs - yet they are one of the most threatened ecosystems on the planet. Not only are corals an integral part of marine ecosystems, they also act as a natural filtration for ocean - contributing to the ocean carbon cycle through photosynthesis, respiration, calcification and dissolution. These processes recycle their nutrients efficiently and sequester huge amounts of carbon from dissolved carbon dioxide as carbonate - so that carbon stays within in the reef system and out of the ocean and atmosphere. 

Coral reefs are incredibly sensitive, so much so that just a one degree change in ocean temperature can cause detrimental effects on all coral reefs in the sea. The impact of the ongoing climate change is directly affecting coral reefs by an already measurable rise of sea water temperature, caused predominantly by human activity.