Authorities are investigating the death of a dolphin found floating in the Mekong River in Kratie province on Tuesday.

Fishermen found the dead male dolphin in a part of the river that runs through Chet Borei district’s Sambok commune, said Kin Sok, a representative of the fishing community.

A river ranger preliminarily attributed the death to a sudden change in water temperature – since there were no marks indicating a net killed the dolphin – but Sok believes illegal fishing tactics are to blame.

“We could not find the injury on the body,” Sok said. “But it could have died from an electric fishing device belonging to illegal fishers.”

Fisheries Administration chief Nao Thuok said his department is investigating the cause of death.

Chhith Sam Ath, country director for the conservation group WWF, lamented the death.

“Dolphins draw national and international tourists to visit the province,” he said.

The dolphin was the fourth found dead in Cambodia this year.