Reports of dead fish floating in the Mekong River and washing up on its banks in Stung Treng’s Thala Barivat district, just south of the controversial Don Sahong Dam on the Laos border, have spurred provincial authorities to look into a potential connection between the deaths and the massive development.

Thiv Meurng Khun, Preah Romkil commune chief, said that for the past month villagers had found dead fish and fragments of dead fish “very often”, with independent activist Chum Huot saying he’d seen dead fish daily since work on the dam began in January and suspected that dynamiting was to blame.

Provincial Fisheries Administration officer Pen Chhundy said his men were dispatched to investigate. “We do not know the cause of the fish deaths yet.”

Meanwhile, downstream, villagers in Kratie’s Chet Borei district found the carcass of an adult Irrawaddy dolphin.

A team from the World Wildlife Fund examined the 162-kilo specimen, and concluded it died of old age, WWF representative Un Chakrey said. Around 80 Irawaddy dolphins remain in the Kingdom, he added.

Additional reporting by Alessandro Marazzi Sassoon