Fish species that undertake mammoth migrations through rivers, lakes and ponds are facing a combined threat from dams, pollution and overfishing preventing them from reaching their breeding grounds.
The golden mahseer and goonch catfish are some of the thirty flagship fish species which have now been prioritised for global conservation by the UN in a new report.
A team of international scientists assessed more than 15,000 species of freshwater migratory fish – which make up half of all fish species – and found their numbers had dropped by an estimated 81% in the last half century.
The authors said for too long the group has been ignored but “are an essential part of people’s livelihoods”.
“Freshwater fish support hundreds of millions of people around the world, so for humans, they’re very important,” said Dr. Zeb Hogan, co-author of the report and professor of biology at University of Nevada, Reno.
As well as providing enough food for 200 million people globally, he said migratory freshwater fish have immense diversity which needs protection.
“You have fish that can get over 650 lb (295kg) that can migrate over 7,000 miles. Every shape and size of animal you can imagine, these beautiful golden dorado that make long-distance migrations in South America, tropical eels that are moving thousands of miles in Oceania,” he said.
The UN first looked at the status of this group back in 2011, but only 3,000 species were assessed. Since then the International Union for the Conservation of Nature (IUCN) has been collecting data on how the populations of many more species are faring.
This time around, the UN was able to look at the condition of more than 15,000 species.
Read on: BBC
