Free-flowing rivers are defined as "rivers that are largely unaffected by human-made changes in its flow and connectivity". These types of ecosystems are crucial to both human populations and other animal species alike. The diverse habitats created by free-flowing rivers have helped with economic growth, food security, and other aspects of human well-being throughout history; but they are also relied on for the survivability of another specific species, the fish.

While rivers may make up only 1% of the surface found on Earth, they also happen to hold about half of all fish species in their waters. The variety of environments created by rivers through differing temperatures or flow has allowed it to cater to many types of fish. Many fish seeking these ideal conditions are inclined to migrate throughout river systems to reach these locations that are best suited for their reproduction in terms of safety and food availability.

However, today free-flowing river ecosystems are being affected due to human industrialisation through the construction of "dams, roads, hydroelectric power plants, dykes, and other physical barriers". These barriers have disturbed the flow and/or the connectivity of many rivers around the world, thereby hindering the ability for fish to reach different areas of these rivers. The human-induced changes have caused fish to struggle in sustaining themselves, and several migratory fish species are becoming scarcer and endangered due to their inability to access their needed environments.

This year, WFMD is on October 24 with the theme of Love Flows. How can you get engaged? Participate in events and/or organise your own event!

Check out www.worldfishmigrationday.com for more information!