Fish once as large as grizzly bears have become far smaller in recent years due to overfishing, dams and climate crisis
The size of megafish in the Mekong River has shrunk alarmingly in recent years owing to overfishing, a study has found. The length of the largest and most endangered freshwater giants, some as big as grizzly bears, decreased by 40% in seven years.
Some fish, like the Mekong giant catfish, have been studied for over a longer period and show a decline in weight of 55% in the past 25 years, dropping from an average of 180kg (397lb) to 80kg.
One of the study team, the biologist Ngor Peng Bun, helped catch a gigantic catfish in 2000 that weighed 270kg, before tagging and releasing it. “It was enormous – unforgettable,” he said, and nearly capsized his boat. The species, known in Khmer as trey reach, or royal fish, is now a shadow of its former self.
The giant barb, the world’s largest carp and Cambodia’s national fish, has shown a similar trajectory. Both species are critically endangered.
