Why in news? 

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.

Highlights:

• The stingray, captured on June 13, measured almost four meters (13 feet) from snout to tail and weighed slightly under 300 kilograms (660 pounds)
• The previous record for a freshwater fish was a 293-kilogram (646-pound) Mekong giant catfish, discovered in Thailand in 2005
• The giant stingray is a very poorly understood fish. Its name, even its scientific name, has changed several times in the last 20 years
• 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

Freshwater fish

• 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 Mekong River

• 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.

Endangered species

• 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

• 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.