Scientist and lecturer Syafyudin Yusuf, 54, dives as he investigates coral in the waters of Badi Island, South Sulawesi province, Indonesia, May 29, 2023. (PHOTO / REUTERS)

SPERMONDE ISLANDS, Indonesia - For nearly two decades, Indonesian marine scientist Syafyudin Yusuf has worked with former poachers to rehabilitate coral reefs destroyed by their use of dynamite for fishing.

They have restored to health 11.5 hectares (roughly 30 acres) of corals around a group of 120 islands known as the Spermonde archipelago in the Makassar Strait off Sulawesi.

Scientist and lecturer Syafyudin Yusuf, 54, shows coral, with a local resident, in the waters of Badi Island, South Sulawesi province, Indonesia, May 29, 2023. (PHOTO / REUTERS)

Coral reefs are increasingly at risk of dying with oceans warming as they absorb greenhouse gas emissions

Fifteen years ago, only 2 percent of the area's original reef area remained undamaged, according to research by Makassar's Hasanuddin University, as fisherfolk used explosives and chemicals, which have now been banned.

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"We enter their lives and try to influence their... mindsets to be able to change from destructive fishing to being conservationists," Syafyudin said, adding that his team anchors frames into the seabed to allow corals to grow undisturbed.

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Indonesia's roughly 5 million hectares of coral reefs account for a fifth of the world's total, according to Greenpeace.

Former poacher Haji Dahrin, 47, and scientist and lecturer Syafyudin Yusuf, 54, spawn corals in aquariums at Badi Island, South Sulawesi province, Indonesia, May 29, 2023. (PHOTO / REUTERS)

Experts say coral reefs are crucial to coastal and marine ecosystems, playing a role in preventing erosion and flooding. They are increasingly at risk of dying with oceans warming as they absorb greenhouse gas emissions.