Atlantic salmon near Stavanger in Norway.. I Photo: Shutterstock/ Jakub Rutkiewicz
Migratory fish, such as salmon, trout and Amazonian catfish, are vital to meet the food security needs, as well as support the livelihoods, of billions of people around the world. They also play a critical role in keeping our rivers, lakes and wetlands healthy by supporting a complex food web. Now, their populations are under immense threat from human-made impacts, requiring urgent action to halt and then reverse the alarming decline.
The collapse in migratory freshwater fish populations is worse in Europe than any other continents. This data is part of an alarming regional trend. In the EU, 60% of rivers, lakes, wetlands and streams are currently not healthy, impacting on the quality and availability of water and the species populations they house, including freshwater fish species (migratory and non-migratory), birds, mammals and amphibians.
The huge number of dams, weirs and barriers in Europe - many for the purposes of hydropower, but also flood defence, irrigation and navigation - is one of the main reasons for the terrible state of rivers and decline in migratory freshwater fish species. Just last month, Europe was shown to be the most obstructed river landscape on the planet, with at least 1 million barriers in operation. This data starkly complements the first Europe-wide mapping of hydropower plants, released by WWF last year, which found the continent’s rivers to be saturated with more than 20,000 hydropower plants, and more than 8,000 additional ones on the cards.
Over 90% of all the existing and planned hydropower plants in Europe are small, generating at most 10 MW of electricity. If all the planned small projects mapped by the study were carried out, their contribution to the total net electricity generation in the EU would be between 0.2 and 2%.
The authors and organisations associated with this report all call upon the global community to protect free-flowing rivers and guide basin-wide planning by addressing existing threats, adhering to ongoing conservation initiatives and water protection laws, investing in sustainable renewable alternatives to the thousands of new hydropower dams that are planned across the world and fostering public and political will as a part of the Emergency Recovery Plan for freshwater biodiversity.
Arjan Berkhuysen, Managing Director of the World Fish Migration Foundation, said, “Catastrophic losses in migratory fish populations show we cannot continue destroying our rivers. This will have immense consequences for people and nature across the globe. We can and need to act now before these keystone species are lost for good.”
Key report findings:
- Globally, monitored populations of migratory freshwater fish have declined by an average of 76% between 1970 and 2016. Average declines have been more pronounced in Europe (-93%) and Latin America & Caribbean (-84%).
- Lower declines in North America (-28%) suggest that management of fisheries could result in a lower average decline in abundance.
- The biggest drivers of population decline are habitat degradation, alteration and loss, and over-exploitation. All of these are inextricably linked to human use and impact.
- The decline in migratory fish populations is in line with the overall decline observed for other freshwater vertebrate populations (83%), which is faster than the rate observed in terrestrial and marine species.
Living Planet Index for Migratory Freshwater Fish >
This text is based on a text published by the WWF on 28 July 2020 >
