The fishermen were dubious when ocean experts suggested they could save their dwindling marine stocks just by switching to new nets.

It took years for the U.N. Development Program to convince the fishing communities along India’s west coast that the diamond-mesh nets they were using were trapping baby fish, while a square-shaped mesh could allow small fish to escape to maintain a breeding population. But two years after the new nets were fully adopted, fishermen insist they’re making a difference.

“This square net is a blessing for us,” said John Gabriel Naronha, who runs six trawlers in the area. “When the small fish grows up, the fishermen c