World’s Largest Freshwater Fish Found in Cambodia

The World’s largest freshwater fish, a 661-pound (300 kilos) giant freshwater stingray, has been found and released in the Cambodian Mekong River.

According to a joint press release, the startling size of the endangered fish, whose weight was confirmed by scientists as twice that of an average lowland gorilla, makes it larger than the 646-pound (293 kilos) Mekong giant catfish caught in Thailand in 2005, which was the previous record-holder for largest freshwater fish on Earth. Freshwater fish are defined as those that have spent their entire lives in freshwater, as opposed to giant marine species like bluefin tuna and marlin, or fish that migrate between fresh and saltwater like the huge beluga sturgeon.

The record-breaking stingray, which measured over 13 feet (almost four meters) from snout to tail, was hooked by a fisher south of the town of Stung Treng, in the middle stretches of the Mekong River as it runs through northern Cambodia. Recognising the importance of his catch, the fisher quickly contacted a team from the USAID-funded Wonders of the Mekong research project to help release the ray, an endangered species, back into the river.

“This historic event highlights the success of USAID’s Wonders of the Mekong project,” said USAID/Cambodia Acting Mission Director Hanh Nguyen. “Cambodia is blessed with incredible biodiversity and we are proud of the team’s efforts to promote sustainable management and raise public awareness on the important role of the Mekong River.”

For the first time ever in Cambodia, the huge ray was fitted with an acoustic tag, technology that will enable biologists to learn more about the secretive creature's elusive behaviour.

For Zeb Hogan, a fish biologist at the University of Nevada, Reno who leads the Wonders of the Mekong, the stingray find is evidence that the natural world can still yield new and extraordinary discoveries, and that many of the largest aquatic creatures remain woefully understudied.

“In 20 years of researching giant fish in rivers and lakes on six continents, this is the largest freshwater fish that we’ve encountered or that’s been documented anywhere worldwide,” Hogan, who is also the host of National Geographic’s “Monster Fish” television series, said. “This is an absolutely astonishing discovery, and justifies efforts to better understand the mysteries surrounding this species and the incredible stretch of river where it lives.”

In collaboration with the Cambodian Fisheries Administration, the Wonders of the Mekong project established a network of fishers who agreed to report catches of giant and endangered fish, including stingrays. Last month, fishers in the same area reported to the team that they had caught a 400-pound giant female stingray, which the research team then helped release safely into the depths of the river.

"The discovery of this world record stingray indicates the special opportunity we have in Cambodia to protect this species and its core habitat. In partnership with the Wonders of the Mekong project, and together with other countries in the Lower Mekong Basin, the Inland Fisheries Research and Development Institute of the Cambodian Fisheries Administration will host a meeting to map out a regional species conservation action plan and solidify safeguards for the river, wildlife, fisheries, and local communities," said H.E. Poum Sotha, Delegate of the Royal Government, Director General of the Fisheries Administration.

Chea Seila, the program manager for Wonders of the Mekong, said “Fishers now cooperate with our project when they find giant stingrays so that we can tag and release them. These successful releases illustrate the importance of partnerships with local communities. Together, we all have an important role to play in fisheries monitoring and conservation.”

Fishers called to inform the team that a “much bigger” ray had been caught during the night of June 13. The stingray was fitted with an acoustic tag to track its movements before being safely returned to the river. It appeared strong and healthy as it quickly descended into the murky depths of the Mekong.

A crowd that included international scientists, Cambodian fisheries officials, and community members gathered for the release of the large female stingray, which they named “Boramy," or “full moon” in the Khmer language, because the round-shaped fish was released at dusk with the moon shining on the horizon.

Source: Agency Kampuchea Press