World's largest freshwater fish caught in Cambodia

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Largest freshwater fish catch in the world

A Cambodian fisherman caught a 661 pound stingray in the Mekong River this month. This is a world record.

A Cambodian fisherman angling for a catch to sell at the local seafood market recently captured a legend that only fish tales are made of and earned his rights to be placed in the Guinness Book of World Records.

In his small boat on the wide Mekong River, lit only by the full moon, he could barely reel in what knew was one of the biggest fish he’d ever caught with his locally made rod and twine, not even fishing line.

Record keepers confirmed that the 661-pound freshwater stingray caught on June 13, was indeed the largest freshwater fish in the world.

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The one that didn't get away – an 18-hour effort

On the river, the fisherman did all he could to keep the stingray on the line and from running. The beast’s weight alone dwarfed his vessel, so there was no way to get the catch into the boat. He called the group ‘Wonders of the Mekong’ to get a payday for the fish whether he could land it or most likely not.

A stingray's mouth is on the underside of their body. This stingray pup in captivity is pressed against glass which gives us a good view. Rays eat fish, mollusks and shrimp.

( HOLGER HOLLEMANN/DPA/AFP via Getty Images / Getty Images)

"He must've gotten a little bit lucky to be able to bring that stingray up to his boat," marveled Zeb Hogan, Director of Wonders of the Mekong and assistant professor at the University of Nevada, Reno, that the rod didn’t break. "These fish are pretty unmanageable for your average fisherman." 

Hogan was in the U.S. when his Cambodian team got the call from the fisherman. The biologist did get an excited play-by-play from fellow researches. 

The Wonders of Mekong team, federally funded by the U.S. Agency for International Development, drove eight hours from the capital to a ferry to take them to an island in the Mekong. At the site, they joined other volunteers and local officials to work a tarp under the giant.

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Largest freshwater catch in the world

A Cambodian fisherman caught a monster 661-pound freshwater stingray.

Over a dozen people dragged the tarp to the shore to measure and weigh the female on three commercial scales with a makeshift wooden platform. Nose to tail, the fish was over 13 feet long and weighed over the equivalent of two standard refrigerators.

The group also tagged the stingray to study its migration pattern before setting it free, 18 hours later. They named the ray, "Boramy" which means "full moon" in Khmer, the native language, and given to girls born on a full moon.

Researchers carefully measured the largest freshwater fish in the world.

Researches had to work carefully around the fish’s tail barb. Anyone who learned the 'Sanibel shuffle' (shuffling your feet through sandy, shallow water to avoid stepping on a skate or stingray) or was familiar with Steve Irwin’s untimely death are aware of the danger.

"This species of stingray has one of the largest barbs of any stingray," said Hogan. "On a big ray, the barb is 8-10 inches long. They can do some serious damage."

The group covered the barb with a cloth for safety while taking measurements.

How the Wonders of the Mekong found the massive fish

The 15-member team that makes up Wonders of the Mekong started studying diversity in the Mekong in 2017. Since then, they have honed their focus to different areas of the river. In April, they started talking to fishermen in a remote, area of northern Cambodia.

"This is one of the reasons why we started focusing in on this area. All the fishermen that live up and down the stretch river have stories of catching a stingray. Some of them even tell stories of catching stingray up to 500 kilos, which would be over 1,000 pounds, which just seems ridiculous," explained Hogan about how he decided to study this remote section of river with pools up to 250 feet deep teaming with wildlife. "And I sort of dismissed those stories, but we kept hearing them over and over." 

This is the third stingray over 300 pounds that fisherman have reported since the project’s re-launch in April. 

Researchers don't know much about the freshwater stingray as they are bottom-dwellers that cover themselves in dirt or sand like this salt-water cousin.

(Barbara Alper/Getty Images / Getty Images)

"These are fish that we have seen chopped up in local markets. And so we knew they're being caught, but they weren't being reported," explained Hogan. "And so we told the fishermen ‘hey, if you catch one of these fish, rather than chopping it up and selling it in the local market, contact us and we'll compensate you at the market rate', which is a little over a dollar-a-pound."

Hogan specializes in studying large freshwater fish. He launched a worldwide project in 2005 to find, study and protect the largest freshwater fish in the world. You may also recognize him from his National Geographic show "Monster Fish." 

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A ‘hopeful sign’ for the future of big fish

"I think this catch came as a surprise to most people. The fact that these fish can still grow so big in a river like the Mekong, where there's a lot of people in the Mekong River, fishing pressure is high, habitat has been degraded recently from dams and pollution," Hogan explained why this discovery was so important. "So the fact that they're still the world's largest fish still occurs in the Mekong River is pretty remarkable. And it's also a hopeful sign."

Dams like this one in northern Cambodia threaten the future of giant freshwater fish.

(Sion Ang/SOPA Images/LightRocket via Getty Images / Getty Images)

"The Mekong River is the most productive river in the world," said Hogan about the group's interest in the river. "Over 2 million tons of fish are harvested from the Mekong every year, and it's also super diverse. So there's about a thousand different kinds of fish."

Most giant freshwater fish are endangered

Hogan said that there are over 30 species of freshwater fish over six feet long and 200 pounds in the world and 70% of those are endangered. 

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"Almost all of the big fish in Asia are endangered," he said. "Most of them are not doing very well, primarily because they need big air, they need big, healthy rivers, they need lots of food, they need protection from being over fished."

In the U.S. big fish populations dropped as well, although the species are not specified endangered:

• Lake Sturgeon in the Great Lakes fell by 90%
• Colorado Pike in the Colorado River of the Desert Southwest fell by 90%

A juvenile Colorado Pike that could grow up to 6 feet long and weigh over 100 pounds. 

(Helen H. Richardson/The Denver Post via Getty Images / Getty Images)

What's next for the group

Hogan and Wonders of the Mekong will continue to study the remote area in northern Cambodia.

"You know, it was amazing, extraordinary that this fish was so big," remarked Hogan. "But this also is only the third fish that we've seen from this site, which suggests there may be even bigger fish out there."

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They hope to tag 200 giant fish of different species and keep track of them with 36 underwater acoustic receivers.

The previous world record holder was a 646 pound Mekong giant catfish caught in Thailand in 2005.

The giant Mekong catfish is critically endangered, according to the International Union for Conservation of Nature.

( Robert Nickelsberg/Getty Images / Getty Images)

"And it was ended up being basically sold for meat. It did not survive," Hogan said regretfully. "This fish was tagged and released back alive into the river. We can actually follow it, watch its movement patterns and learn about its habitat."

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