Natural Resources and Environment Minister Varawut Silpa-archa has expressed concerns over the low population of Irrawaddy dolphins in Thailand and urged all parties to step up efforts to help protect the critically endangered species.
Citing a survey from 2020, the minister said there were only 14 Irrawaddy dolphins in Songkhla Lake and 89 in the Mekong River, while about six of the dolphins were found dead on a beach between 2006 and last year.
Mr Varawut said the cause of death of these mammals couldn't be proven definitively as their carcasses were badly decomposed by the time they were found.
He said the number of Irrawaddy dolphins found dead ashore had declined in 2015, an indication that a campaign carried out from 2014 to 2015 to encourage fishermen operating in Songkhla Lake to avoid using huge fishing nets to catch giant catfish had paid off.
At the time, various conservation efforts were carried out to urge fishermen to stop using huge fishing nets, which are believed to injure or kill Irrawaddy dolphins when used.
"One of the key activities was offering to buy those giant fishing nets -- [which are] about 1.5 to 3 kilometres long -- using funds raised by various organisations," Mr Varawut said.
"It appeared to have worked considering fewer dolphins were found caught in giant fishing nets."
But he said the trend did not last.
"Between 2020 and last year, at least two Irrawaddy dolphins were found dead in a huge fishing net after some fishermen used it to catch giant catfish in Songkhla Lake," Mr Varawut said.
The Mekong giant catfish was first brought to the lake by various organisations many years ago to increase their population, he said.
As time passed and many of the catfish grew, fishermen began making giant nets to catch them because the fish sell at a high price, he said.
The practice, he said, is a real threat to the lake's Irrawaddy dolphin population and persists despite warnings about the environmental effects.
He said freshwater dolphins are found only in the Irrawaddy River in Myanmar, Mekong River in Laos and Cambodia, Mahakam River in Indonesia, Chilika Lake in India and Songkhla Lake in Thailand.
