In Fiji, a South Pacific nation of more than 300 islands, local communities play a central role in managing their immediate waters. As a result, community-based programs that try to increase awareness of declining turtle stocks and to expand monitoring efforts “are those with the highest probability of success,” said Dr. Susanna Piovano, a senior lecturer at the School of Marine Studies at the University of the South Pacific.

Traditionally turtles were eaten at major events, like a wedding or a chief’s funeral. As traditions eroded in recent decades, some people began to think of turtles and their eggs as an everyday food to catch and sell.

Climate change and habitat loss have also placed pressure on the turtle population. The conservation status of the turtles common to Fiji’s waters — green, olive ridley, leatherback, hawksbill and loggerhead — ranges from vulnerable to critically endangered, according to the Red List of Endangered Species published by the International Union for Conservation of Nature.

The Fiji government imposed a temporary ban on turtle harvesting in 1995 to halt the decline. The current 10-year moratorium is scheduled to expire next year.

Still, the moratoriums have not stopped many communities from continuing to harvest turtles.

Yadua was one of them — at least until the island experienced something of a road-to-Damascus conversion. In 2010, two organizations — the World Wildlife Fund and the Secretariat of the Pacific Regional Environment Programme, an intergovernmental group — organized a workshop on the island. They presented a somber vision of the turtles’ potential extinction and discussed ways to prevent that.

It was there that Mr. Qarau realized future generations might never see or taste a turtle if harvesting continued. He said he was not thinking of himself when he decided to give up hunting turtles. “I am thinking about the future generations,” he said.