On Son Island in Vietnam’s Mekong Delta, Le Trung Tin scatters fish feed into his ponds, where dozens of snakehead fish leap through the surface in synchronised bursts. “I taught them how to do that,” ...

As he winds his way along narrow paths on Son Island, Le Trung Tin explains how plastic pollution forced him to shift from fishing in Vietnam’s Mekong Delta to fish farming in filtered ponds.