Evan Bush
Mon, June 20, 2022,
A fisherman in northern Cambodia hooked what researchers say is the world’s largest freshwater fish — a giant stingray that scientists know relatively little about.
The fisherman, 42, caught the 661-pound fish — which measured about 13 feet in length — near a remote island on the Mekong River in the Stung Treng area. A team of scientists from the Wonders of Mekong research project helped tag, measure and weigh the ray before it was released back into the river. The research group believes it was healthy when released and expects it to survive.
The tag — which emits an acoustic signal — will allow researchers to track the fish’s movements and, they hope, learn more about its species’ behavior in the Mekong.
The catch “highlights how little we know about a lot of these giant freshwater fish,” said Zeb Hogan, a fish biologist at the University of Nevada. “You have a fish that’s now the record holder for the world’s largest freshwater fish, and we know little about it.”
The giant freshwater stingray was captured the night of June 13, 2022 near Koh Preah island in the Mekong River in northern Cambodia. It was accidentally hooked by a 42-year-old fisherman named Moul Thun. (Chhut Chheana / Wonders of the Mekong)
The fisherman, Moul Thun, caught the giant stingray with a hook and line on the evening of June 13, and then contacted researchers the next morning.
Researchers with the Wonders of Mekong were already in northern Cambodia to install underwater receivers as part of a project to track migratory fish in the river.
“It’s a particularly healthy stretch of the river with a lot of deep pools — pools up to 90 meters deep,” said Hogan, who is also the host of National Geographic’s “Monster Fish” television series. “We started focusing on this area as a stretch of river that’s particularly important for biodiversity and fisheries, and as a last refuge for these big species.”
For several months, the research group has been in contact with local fishermen, asking them to get in touch if they landed a significant catch. The group has helped with two other large giant freshwater stingray releases in recent months. The fisherman who caught the record ray was paid market price for his catch.
“It works because the fish is not a highly prized food fish,” Hogan said.
Hogan said little is known about the giant freshwater stingray. The creature has a mouth about “the size of a banana” with no teeth, but with “gripping pads” used to crush prey.
“They’re on the bottom finding shrimps, mollusks and small fish. They can suck them up with this banana-shaped mouth and crush them,” Hogan said.
Wonders of the Mekong team members, Cambodian fisheries officials, and villagers took photos with the giant freshwater stingray. (Chhut Chheana / Wonders of the Mekong)
Fishermen have reported three catches of female stingrays in the area during the past two months, Hogan said. The scientists suspect the site could be an important seasonal gathering site for giant freshwater stingrays, and might serve as a pupping ground for young.
The research group plans to tag and track a few hundred big fish in the Mekong River to better understand fish migrations and local habitat in the upper Cambodian Mekong.
“There’s potential for hydropower development right where these stingrays were caught,” Hogan said. “We want to understand the importance of this area before there’s development, potentially in an unsustainable way.”
Hogan said the Cambodian government has expressed interest in developing a conservation plan for the giant freshwater stingrays.
The upper Mekong is also habitat for Mekong giant catfish and other species of large freshwater fish.
Worldwide, “most of these species of big fish are in trouble, their populations are declining. The Chinese paddlefish was declared extinct in 2020,” Hogan said. “We need to do more to protect these freshwater habitats.”
The former world record holding fish — a 646-pound Mekong giant catfish — was also caught on the Mekong River in 2005, in Thailand.
There are other, larger recorded catches of fish that spend time in both fresh and saltwater, such as the beluga sturgeon.
“This is the record for the largest fish that has spent its entire life in freshwater,” Hogan said of the recently caught ray.
Mon, June 20, 2022,
A fisherman in northern Cambodia hooked what researchers say is the world’s largest freshwater fish — a giant stingray that scientists know relatively little about.
The fisherman, 42, caught the 661-pound fish — which measured about 13 feet in length — near a remote island on the Mekong River in the Stung Treng area. A team of scientists from the Wonders of Mekong research project helped tag, measure and weigh the ray before it was released back into the river. The research group believes it was healthy when released and expects it to survive.
The tag — which emits an acoustic signal — will allow researchers to track the fish’s movements and, they hope, learn more about its species’ behavior in the Mekong.
The catch “highlights how little we know about a lot of these giant freshwater fish,” said Zeb Hogan, a fish biologist at the University of Nevada. “You have a fish that’s now the record holder for the world’s largest freshwater fish, and we know little about it.”
The giant freshwater stingray was captured the night of June 13, 2022 near Koh Preah island in the Mekong River in northern Cambodia. It was accidentally hooked by a 42-year-old fisherman named Moul Thun. (Chhut Chheana / Wonders of the Mekong)
The fisherman, Moul Thun, caught the giant stingray with a hook and line on the evening of June 13, and then contacted researchers the next morning.
Researchers with the Wonders of Mekong were already in northern Cambodia to install underwater receivers as part of a project to track migratory fish in the river.
“It’s a particularly healthy stretch of the river with a lot of deep pools — pools up to 90 meters deep,” said Hogan, who is also the host of National Geographic’s “Monster Fish” television series. “We started focusing on this area as a stretch of river that’s particularly important for biodiversity and fisheries, and as a last refuge for these big species.”
For several months, the research group has been in contact with local fishermen, asking them to get in touch if they landed a significant catch. The group has helped with two other large giant freshwater stingray releases in recent months. The fisherman who caught the record ray was paid market price for his catch.
“It works because the fish is not a highly prized food fish,” Hogan said.
Hogan said little is known about the giant freshwater stingray. The creature has a mouth about “the size of a banana” with no teeth, but with “gripping pads” used to crush prey.
“They’re on the bottom finding shrimps, mollusks and small fish. They can suck them up with this banana-shaped mouth and crush them,” Hogan said.
Wonders of the Mekong team members, Cambodian fisheries officials, and villagers took photos with the giant freshwater stingray. (Chhut Chheana / Wonders of the Mekong)
Fishermen have reported three catches of female stingrays in the area during the past two months, Hogan said. The scientists suspect the site could be an important seasonal gathering site for giant freshwater stingrays, and might serve as a pupping ground for young.
The research group plans to tag and track a few hundred big fish in the Mekong River to better understand fish migrations and local habitat in the upper Cambodian Mekong.
“There’s potential for hydropower development right where these stingrays were caught,” Hogan said. “We want to understand the importance of this area before there’s development, potentially in an unsustainable way.”
Hogan said the Cambodian government has expressed interest in developing a conservation plan for the giant freshwater stingrays.
The upper Mekong is also habitat for Mekong giant catfish and other species of large freshwater fish.
Worldwide, “most of these species of big fish are in trouble, their populations are declining. The Chinese paddlefish was declared extinct in 2020,” Hogan said. “We need to do more to protect these freshwater habitats.”
The former world record holding fish — a 646-pound Mekong giant catfish — was also caught on the Mekong River in 2005, in Thailand.
There are other, larger recorded catches of fish that spend time in both fresh and saltwater, such as the beluga sturgeon.
“This is the record for the largest fish that has spent its entire life in freshwater,” Hogan said of the recently caught ray.
Cambodian catches world's largest recorded freshwater fish
JERRY HARMER
Mon, June 20, 2022
BANGKOK (AP) — The world’s largest recorded freshwater fish, a giant stingray, has been caught in the Mekong River in Cambodia, according to scientists from the Southeast Asian nation and the United States.
The stingray, captured on June 13, measured almost four meters (13 feet) from snout to tail and weighed slightly under 300 kilograms (660 pounds), according to a statement Monday by Wonders of the Mekong, a joint Cambodian-U.S. research project.
The previous record for a freshwater fish was a 293-kilogram (646-pound) Mekong giant catfish, discovered in Thailand in 2005, the group said.
The stingray was snagged by a local fisherman south of Stung Treng in northeastern Cambodia. The fisherman alerted a nearby team of scientists from the Wonders of the Mekong project, which has publicized its conservation work in communities along the river.
The scientists arrived within hours of getting a post-midnight call with the news, and were amazed at what they saw.
“Yeah, when you see a fish this size, especially in freshwater, it is hard to comprehend, so I think all of our team was stunned,” Wonders of the Mekong leader Zeb Hogan said in an online interview from the University of Nevada in Reno. The university is partnering with the Cambodian Fisheries Administration and USAID, the U.S. government’s international development agency.
Freshwater fish are defined as those that spend their entire lives in freshwater, as opposed to giant marine species such as bluefin tuna and marlin, or fish that migrate between fresh and saltwater like the huge beluga sturgeon.
The stingray's catch was not just about setting a new record, he said.
“The fact that the fish can still get this big is a hopeful sign for the Mekong River, ” Hogan said, noting that the waterway faces many environmental challenges.
The Mekong River runs through China, Myanmar, Laos, Thailand, Cambodia and Vietnam. It is home to several species of giant freshwater fish but environmental pressures are rising. In particular, scientists fear a major program of dam building in recent years may be seriously disrupting spawning grounds.
“Big fish globally are endangered. They’re high-value species. They take a long time to mature. So if they’re fished before they mature, they don’t have a chance to reproduce,” Hogan said. “A lot of these big fish are migratory, so they need large areas to survive. They’re impacted by things like habitat fragmentation from dams, obviously impacted by overfishing. So about 70% of giant freshwater fish globally are threatened with extinction, and all of the Mekong species.”
The team that rushed to the site inserted a tagging device near the tail of the mighty fish before releasing it. The device will send tracking information for the next year, providing unprecedented data on giant stingray behavior in Cambodia.
“The giant stingray is a very poorly understood fish. Its name, even its scientific name, has changed several times in the last 20 years,” Hogan said. “It’s found throughout Southeast Asia, but we have almost no information about it. We don’t know about its life history. We don’t know about its ecology, about its migration patters.”
Researchers say it’s the fourth giant stingray reported in the same area in the past two months, all of them females. They think this may be a spawning hotspot for the species.
Local residents nicknamed the stingray "Boramy,” or “full moon,” because of its round shape and because the moon was on the horizon when it was freed on June 14. In addition to the honor of having caught the record-breaker, the lucky fisherman was compensated at market rate, meaning he received a payment of around $600.
JERRY HARMER
Mon, June 20, 2022
BANGKOK (AP) — The world’s largest recorded freshwater fish, a giant stingray, has been caught in the Mekong River in Cambodia, according to scientists from the Southeast Asian nation and the United States.
The stingray, captured on June 13, measured almost four meters (13 feet) from snout to tail and weighed slightly under 300 kilograms (660 pounds), according to a statement Monday by Wonders of the Mekong, a joint Cambodian-U.S. research project.
The previous record for a freshwater fish was a 293-kilogram (646-pound) Mekong giant catfish, discovered in Thailand in 2005, the group said.
The stingray was snagged by a local fisherman south of Stung Treng in northeastern Cambodia. The fisherman alerted a nearby team of scientists from the Wonders of the Mekong project, which has publicized its conservation work in communities along the river.
The scientists arrived within hours of getting a post-midnight call with the news, and were amazed at what they saw.
“Yeah, when you see a fish this size, especially in freshwater, it is hard to comprehend, so I think all of our team was stunned,” Wonders of the Mekong leader Zeb Hogan said in an online interview from the University of Nevada in Reno. The university is partnering with the Cambodian Fisheries Administration and USAID, the U.S. government’s international development agency.
Freshwater fish are defined as those that spend their entire lives in freshwater, as opposed to giant marine species such as bluefin tuna and marlin, or fish that migrate between fresh and saltwater like the huge beluga sturgeon.
The stingray's catch was not just about setting a new record, he said.
“The fact that the fish can still get this big is a hopeful sign for the Mekong River, ” Hogan said, noting that the waterway faces many environmental challenges.
The Mekong River runs through China, Myanmar, Laos, Thailand, Cambodia and Vietnam. It is home to several species of giant freshwater fish but environmental pressures are rising. In particular, scientists fear a major program of dam building in recent years may be seriously disrupting spawning grounds.
“Big fish globally are endangered. They’re high-value species. They take a long time to mature. So if they’re fished before they mature, they don’t have a chance to reproduce,” Hogan said. “A lot of these big fish are migratory, so they need large areas to survive. They’re impacted by things like habitat fragmentation from dams, obviously impacted by overfishing. So about 70% of giant freshwater fish globally are threatened with extinction, and all of the Mekong species.”
The team that rushed to the site inserted a tagging device near the tail of the mighty fish before releasing it. The device will send tracking information for the next year, providing unprecedented data on giant stingray behavior in Cambodia.
“The giant stingray is a very poorly understood fish. Its name, even its scientific name, has changed several times in the last 20 years,” Hogan said. “It’s found throughout Southeast Asia, but we have almost no information about it. We don’t know about its life history. We don’t know about its ecology, about its migration patters.”
Researchers say it’s the fourth giant stingray reported in the same area in the past two months, all of them females. They think this may be a spawning hotspot for the species.
Local residents nicknamed the stingray "Boramy,” or “full moon,” because of its round shape and because the moon was on the horizon when it was freed on June 14. In addition to the honor of having caught the record-breaker, the lucky fisherman was compensated at market rate, meaning he received a payment of around $600.
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