The Mekong River Wonder project – in collaboration with the Inland Fisheries Research and Development Institute (IFREDI) – released a gigantic freshwater stingray back into the river, after it was caught by fishermen on May 22 in Koh Preah commune of Stung Treng province’s Siem Bok district.

Sam Vichet, head of the Fisheries Administration’s (FiA) provincial cantonment, said the fish weighed 143kg and was 171cm wide. Its body was 181cm long, but when measured from the tip of the nose to the tip of the tail, it was 365cm in length.

Before releasing it back into the Mekong River on May 23, Mekong River Wonder officials and IFREDI researchers removed the fisherman’s hook from its mouth and chipped it with a marker and location beacon so its activities could be monitored.

“Freshwater stingrays are a vulnerable and endangered species. In general, they live in deep water – like the Mekong freshwater dolphins,” he said.

He added that Koh Preah is part of the Mother Fish Conservation Area, and is home to such rare species as the thin lip barb, Mekong giant catfish and Mekong giant barb. It is one of the deepest parts of the Mekong, and is strictly guarded by the officials of the FiA’s provincial cantonment, fishing communities and local authorities.

Pheng Boeun, head of the Koh Preah fishing community, told The Post that the stingray had repeatedly gotten tangled in fishing hooks and lines, which raised concerns that the species is under threat from fishing activities.

“At first, we were filled with joy at having the opportunity to be in the presence of this rare and endangered giant stingray. When we saw it tangled in the lines of our fishermen, it made us think that the species must be facing a number of problems, including potentially a lack of food,” he said.