Arbitrage Life: BIIIIIG Fish in a Little Pond

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 4 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.