Rare giant catfish faces new threat in Southeast Asia's Mekong
Laos' controversial Xayaburi Dam could bring the Giant Catfish to extinction, as well as devastate the Mekong River's other fisheries. The challenge: How to build a dam that allows a 600-pound fish to swim up stream?
The Giant Catfish is an enormous fish with thin, down-turned lips that give it a lonely look. And such a "mournful" visage is not unwarranted.Skip to next paragraph
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Already one of the most endangered fish in the world, a new study has found that a dam under way in Laos could push it to extinction.
So rare that it is nearly a legend of the Mekong River’s depths, the Giant Catfish belongs to the shark catfish family and reach more than 600 pounds and some 10 feet in length. The Brobdingnagian fish has dwindled in number an estimated 90 percent over the past 20 years – possibly to just a few hundred animals, though tracking the elusive fish is difficult. It is now found only in the lower Mekong, which runs like a mud-colored vein carrying the economic lifeblood of Southeast Asia through Laos, Myanmar, Thailand, Cambodia, and Vietnam. In recent years, though, progress had been made in rescuing Giant Catfish fish from extinction, as those five countries introduced new protections that banned fishing it.
Now, Laos's controversial Xayaburi Dam threatens to undo that.
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“The Giant Catfish is endangered, but there’s still a chance for it, and all the countries involved have gotten on board to restrict fishing – but just when we solved one problem we’re now facing this new one,” says Zeb Hogan, the study’s author and associate research professor at the University of Nevada, in a telephone interview.
The Xayabari, the first dam in the lower Mekong, will, if finished, block the Giant Catfish from making its lifecycle migration from the floodplain rearing areas to upstream spawning sites in northern Laos and Thailand, the study said. The dam could also alter Mekong flows, disrupting the natural cues the fish needs to spawn.
This is not the first warning that the Xayabari project could mean the end for the Giant Catfish. Two years ago, the Mekong River Commission – an advisory body established in 1995 as part of an agreement between five Southeast Asian countries on the development of the Mekong – convened a panel of experts who concluded that the dam would obstruct the migrations of some 23 to 100 species of fish, including the Great Catfish. The panel recommended a 10-year hold on the Xayaburi project, pending more information on how the dam would affect the river’s ecology.
"The gaps in knowledge on the number of migratory fish species, their biomass and their ability to successfully pass a dam and reservoir leads to considerable uncertainty about the scale of impact on fisheries and associated livelihoods, both locally and in a transboundary context," the report said.
But in November 2012, Laos officially began what is expected to be seven years of construction of the Xayabari Dam, the first in several controversial dams planned for the lower Mekong.