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Dog-eating catfish, other river giants threatened by Mekong dam plan

This post is part of a special National Geographic news series on global water issues. Wild populations of the iconic Mekong giant catfish will be driven to extinction if hydropower dams planned for the Mekong River go ahead, says a report released by World Wildlife Fund (WWF) today.   Mekong giant catfish photo (c) Suthep...

This post is part of a special National Geographic news series on global water issues.

Wild populations of the iconic Mekong giant catfish will be driven to extinction if hydropower dams planned for the Mekong River go ahead, says a report released by World Wildlife Fund (WWF) today.

 Giant Catfish _Pangasianodon gigas_ ©Sut.jpg

Mekong giant catfish photo (c) Suthep Kritsanavarin/WWF-Canon

The report, River of Giants: Giant Fish of the Mekong, profiles four giant fish living in the Mekong that rank within the top 10 largest freshwater fish on the planet. “At half the length of a bus and weighing up to 1,322 pounds, the Mekong River’s giant freshwater stingray is the world’s largest freshwater fish. The critically endangered Mekong giant catfish ranks third at almost 10 feet in length and 771 pounds,” WWF says in a news release accompanying the report.

National Geographic Mekong giant catfish video courtesy of Zeb Hogan

Sayabouly dam.jpg

Map courtesy of WWF

The hydropower dam planned on the Mekong River at Sayabouly Province, northern Laos, is a threat to the survival of the wild population of Mekong giant catfish. The Sayabouly dam is the first lower Mekong River mainstream dam to enter a critical stage of assessment before construction is approved by the Mekong River Commission, which includes representatives from Cambodia, Laos, Thailand and Vietnam, WWF explained.

River of Giants cover.jpg“A fish the size of a Mekong giant catfish cannot swim across a large barrier like the Sayabouly dam to reach its spawning grounds upstream,” said Dekila Chungyalpa, Director of WWF’s Greater Mekong Program. “Building this and other dams will lead to the collapse of the wild population of this iconic species.”

Current scientific information suggests the Mekong giant catfish migrate from the Tonle Sap Lake in Cambodia up the Mekong River to spawn in northern Thailand and Laos. Any dam built on the lower Mekong River mainstream will block this migration route, WWF said.

“The other Mekong giant fish featured in the report are the dog-eating catfish, named because it has been caught using dog meat as bait, and the giant barb, the national fish of Cambodia and largest barb in the world. At 661 pounds each, these fish tie for fifth place on the global top ten,” WWF noted.

Dog-eating Catfish _Pangasius sanitwongse.JPG

Photo of giant dog-eating catfish (c) Jean-Francois Helias/courtesy of WWF

“The impacts of lower Mekong River mainstream dams are not restricted to these Mekong giants; they would also exacerbate the impacts of climate change on the Mekong River Delta, one of the world’s most productive regions for fisheries and agriculture.

“Building the Sayabouly dam would reduce sediment flowing downstream to the Mekong River Delta, increasing the vulnerability of this area to the impacts of climate change like sea level rise,” WWF said.

Mekong dams.jpg

Map courtesy of WWF

“The Lower Mekong is currently free-flowing but the clock is ticking,” Chungyalpa said. “We have a rare opportunity to conserve these freshwater giants and ensure the livelihoods of millions of people who live along the Mekong mainstream.”

Giant Barb _Catlocarpio siamensis_ ©Zeb .jpg

Photo of giant barb (c) Zeb Hogan/Courtesy of WWF

WWF supports a delay in the approval of the mainstream dams, including the Sayabouly dam, to ensure a comprehensive understanding of all the positive and negative impacts of their construction and operation.

“To meet immediate energy demands, WWF promotes sustainable hydropower projects on tributaries of the Mekong River, prioritizing those that already have hydropower dams developed on them,” the conservation charity said.

Click on the images below to enlarge a selection of pages from the WWF report River of Giants: Giant Fish of the Mekong. Visit WWF’s Greater Mekong website to learn more.

The Might Mekong page_click to enlarge.jpg

Giant freshwater stingray.jpg
Giant dog-eating catfish.jpg
Mekong giant catfish.jpg

Posted by David Braun

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Author Photo David Max Braun
More than forty years in U.S., UK, and South African media gives David Max Braun global perspective and experience across multiple storytelling platforms. His coverage of science, nature, politics, and technology has been published/broadcast by the BBC, CNN, NPR, AP, UPI, National Geographic, TechWeb, De Telegraaf, Travel World, and Argus South African Newspapers. He has published two books and won several journalism awards. In his 22-year career at National Geographic he was VP and editor in chief of National Geographic Digital Media, and the founding editor of the National Geographic Society blog, hosting a global discussion on issues resonating with the Society's mission and initiatives. He also directed the Society side of the Fulbright-National Geographic Digital Storytelling Fellowship, awarded to Americans seeking the opportunity to spend nine months abroad, engaging local communities and sharing stories from the field with a global audience. A regular expert on National Geographic Expeditions, David also lectures on storytelling for impact. He has 120,000 followers on social media: Facebook  Twitter  LinkedIn