UNSPOILED RIVERS ARE THE EPITOME OF UNTAMED NATURE. DESPITE THEIR WILDNESS – OR RATHER BECAUSE OF IT – THEY ARE FULL OF LIFE AND ESSENTIAL FOR ECOLOGICAL PROCESSES.
...runs like a green ribbon through the Kuururjuaq National Park in Nunavik in the extreme northeast of Quebec. Vegetation can only grow in the valley created by the river itself, which stands out clearly from the barren mountains in the surrounding area. The landscape is rugged and intimidating, characterized by rock and snow, grasses and moorland. Light stands of spruce, larch, and white birch adorn the lowlands and mountain slopes. Here, survival takes toughness and endurance, and it is managed by only a few highly adapted species such as Spruce Grouse, Willow Ptarmigan, and Arctic fox. In summer, caribou also range huge distances to feed on grass, lichen, and moss.
Unspoiled rivers like the Koroc are not just a habitat for animals and plants but are also vital for humans because they perform essential functions within the ecosystem. Natural, flowing waters provide us with water, food, timber, and other resources. They also regulate the climate, prevent erosion, and help with water purification. In addition, they bring social and cultural benefits, such as recreation and tourism. It is no coincidence that many of the first settlements were established along rivers. Even today, many of our modern cities are located on rivers, which are still important trading and transportation routes.
Decades of flood protection, energy generation, and promotion of shipping have resulted in the fact that the major rivers in the densely populated areas of America, Europe, and Asia have little in common with the wild rivers they once were. However, there still are real wild rivers. Most of them are in remote areas of the far north. But even further south, in places like Italy, Albania, and Montenegro, there are a few rivers and sections that have remained largely unspoiled.
There’s an old saying: “You never jump in the same river twice.” The character of a river changes drastically as it flows from source to estuary. Its flow rate, temperature, and nutrient content typically increase, while the oxygen content, flow speed, and size of the particles on the riverbed decrease. The entire ecosystem is constantly changing, something that is particularly evident after floods. Areas that were previously gravel are now water. Where trees grew is now a steep bank. Elsewhere, new banks are created, and fine sediment is deposited in the floodplains. This creates a multitude of small and micro habitats, which differ in depth, flow rate, temperature, and substrate – a mosaic of closely interwoven biotopes.
The majority of river organisms depend on this interlocked sequence of habitats. They can suffer severe population losses or even disappear if even one key habitat is missing or inaccessible. Typical river fish such as trout and salmon (Salmonidae) or many representatives of the carp family (Cyprinidae) such as barbel or nase require shallow, fast-flowing gravel areas for spawning, but as young fish, they require quieter bank areas. The adult fish colonize fast-flowing sections in open water or on the riverbed. Deep basins or accumulations of deadwood serve as winter shelters.
The remaining wild rivers have been spared from today’s over-development. They continue to flow steadily through the landscape that they themselves have shaped, bringing the rain back to the sea and slowly wearing away the mountains, piece by piece. Preserving them for future generations is both a duty and labor of love because there is so much we can learn from wild rivers. Things like persistence, peace, and energy in harmony. A sense of togetherness and the realization that diversity is the foundation of a functioning ecosystem bringing it beauty and richness.
David Ramler, PhD, worked as a fish ecologist at the University of Vienna and is a freelance biologist. His latest research looks at restoration projects in the Danube.