Fishing nets and bamboo fishing traps are ubiquitous features of almost every home in the Mekong River fishing villages of Bokeo Province, northern Laos.

The mountainous province of Bokeo is a part of the “golden triangle” between Laos, Myanmar and Thailand, and for locals like Mr Bounthan Swatdee, a 57-year-old fisherman from Tinthat village, fishing the Mekong has been a way of life for over 30 years.

“My father taught me how to be a fisherman, and now I am teaching my sons,” said Mr Bounthan. “We call the river mae nam khon, which in Lao means Mother Mekong, because it gives us so much in our life.”

Beginning in the Tibetan plateau, the Mekong River winds 4,880 kilometres through China, Myanmar, Laos, Thailand and Cambodia before emptying into the Mekong Delta in Vietnam and then into the South China Sea. For Mr Bounthan and his family, like 60 million others living off the Mekong across this region, the river provides fish for his family to eat and sell, a place to bathe and wash clothes, a means for navigation, and irrigation for their rice field.

“This one is called mong in Lao language,” said Mr Bounthan, stretching the large gill net out like a curtain. “We use this to drag behind the boat in the Mekong around Don Poung and Don Veng islands,” he said.

The Mekong is a seasonal river and during the dry season water levels drop, uncovering islands and sandbanks that locals use to fish.

The next fishing net he produces has a series of small weights along the bottom. While standing in their wooden long-tail boats or in shallow waters, fishermen use this to cast off their shoulder, so the net fans out across the water.

But more than just a source of food security and livelihoods, the Mekong is a part of local culture and tradition.

Fishing communities in Bokeo and across the river in Chaing Rai, Thailand, are at the heart of a tradition revolving around the Mekong giant catfish, the third-largest freshwater fish in the world. It weighs up to 350kgs and reaches up to three meters in length.

“I used catch Pa Pbuk,” said Mr Leuam, a 62-year-old fisherman from Pa Oi village, of the Mekong giant catfish. “In Lao culture, Pa Pbuk is one of the river spirits that brings good luck to your fishing season if you catch it,” he explained.

Historically, Mekong giant catfish occurred along the entire Mekong River from Yunnan Province in China to the Mekong Delta in Vietnam. However, overfishing of the species in the 1980s and 1990s caused a huge decline in numbers. Recently, Laos and Thai governments declared a moratorium on catching this critically endangered species, as there are only a few hundred adult fish left in the wild.

“Now Pa Pbuk are too rare to catch,” said Mr Leuam. “I think we need to protect Pa Pbuk because if we lose a river spirit it is a bad omen for fisherman.”

“I have seen a lot of change to the river. More hotels, restaurants, ships. It has changed the river and many say there are less fish to catch because of it. We are also worried about the dams,” he said.

Even with the moratorium in place, the Mekong giant catfish could still be driven to extinction if any of the 11 proposed hydropower dams on the lower Mekong River mainstream go ahead.

The lower section of the Mekong River is still free-flowing as it runs from the border with China through Laos, Cambodia, Thailand and Vietnam. However, if just one dam is built, the food security of over 60 million people will be at risk.

“In many ways, the challenges faced by the Mekong giant catfish are symbolic of challenges faced by the Mekong River as a whole,” said Marc Goichot, Sustainable Infrastructure Senior Advisor for WWF’s Greater Mekong Programme.

“There are 1,100 species of fish in the Mekong. The technology does not exist to allow such a large and diverse fish migration through a dam. Any dam on the lower Mekong River would block fish migration to spawning grounds, collapsing fish stocks,” he said.

Forecasts from the Mekong River Commission show damming the lower Mekong would reduce fishery productivity by more than 60 percent. To paraphrase the UN’s Food and Agriculture Organization, the amount of fish lost would be the equivalent to up to 3.5 times the entire beef production of Cambodia, Laos, Thailand and Vietnam. This would directly impact the food security and livelihoods of 60 million people dependent on the Mekong’s fishery.

Hydropower development is seen as an avenue to poverty alleviation for Cambodia and Laos, and a source of energy for Thailand and Vietnam. However, gaps in the understanding of ecosystem functions, and impacts on fisheries and sediment dynamics prevent accurate measurements of the risks associated with their construction.

WWF supports a delay in the approval of the mainstream dams to ensure a comprehensive understanding of all the impacts of their construction and operation.

To meet immediate energy demands, WWF promotes sustainable hydropower projects on selected tributaries, and not the lower mainstream of the Mekong River.

There is a small window of opportunity to conserve this mighty river and its species, upon which millions of people like Mr Bounthan and his family have depended for generations.