A new report from the World Wildlife Fund (WWF) shows that populations of migratory freshwater fish globally have been reduced by 81 percent over the past five decades. The report, titled “Living Planet Index,” has examined 284 species of migratory freshwater fish – including eels, salmon, and trout – across 1800 populations since 1970. These fish live partially or entirely in freshwater and many of them migrate between the sea and freshwater, such as rivers, streams, and lakes.
The situation is particularly dire in Central America, where the population of migratory freshwater fish has declined by a staggering 91 percent. In Europe, the decline is at 75 percent. The drastic decrease in fish populations is primarily due to the destruction, pollution, and obstruction of their natural habitats. Hydropower plants are among the biggest culprits, blocking the fish’s migration routes and damaging their habitats.