There was a time when Nengah Arsana would take cyanide with him when he went out fishing. The poison would sedate the fish and make them easy to catch.

But when the coral started to die and the fish disappeared, he realised that something was going terribly wrong. The whole fishing community lost its livelihood and decided to change its habits.

“Now we protect our corals by just using nets for fishing because we realise that fish can’t live without coral,” he told Al Jazeera. “Since we have stopped using cyanide, our business has picked up again.”

With help from a coral-rehabilitation programme, the habitat of the fish has grown back and the fishermen have become coral experts.

“We have to clean the replanted corals with a brush,” Eka, another fisherman, said. “It’s important to do this very gently, otherwise the coral will be stressed.”

The fisherman have realised the need to protect the coral to protect their livelihoods. But if the reef is damaged by climate change, there is nothing they can do about it.

With simple means like concrete and a brush, they managed to restore parts of the reef.