A child poses with the head of a Mekong giant catfish caught at Khone Falls in Laos in August last year.

The giant catfish was once plentiful throughout the Mekong River system, but in the last century the population has declined 95 to 99 percent, according to Hogan of the Megafishes Project.

Last year only one giant catfish was caught at Khone Falls.

"Everyone heard about the catch, and hundreds of people showed up to look at it," said photographer Suthep Kritsanavarin.

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