The village where Vo Linh Hue lives is dotted with oyster farms, but in recent weeks farmers there have done nothing but clear dead oysters from the ponds.

Ben Tre province, in Vietnam's southern Mekong Delta, is experiencing the worst drought in recent history, and saline intrusion has hit rice and oyster farmers especially hard.

"This is the area where the river flows into the city. But now the seawater has pushed inland and killed all the oysters," said Hue, 23, whose family lives in the Ben Tre village of Thua Thanh and has relied on oyster farming for decades.