*River mussels. Photo: Bjørn Medjell Larsen, NINA*

Insect buzzing and birdsong in the river valleys

It's high summer. The summer river is warm and the young salmon have a high level of activity. They are eating and growing. Adult salmon are still coming in from the sea. There is life both in and by the river now. Even without a fishing rod, you can enjoy many nature experiences. The surface can suddenly be broken by a "rolling" adult salmon, and if you take your time, you can spot the very smallest salmon in the river. You may see young salmon in different year classes darting out from their hiding places to grab something edible before swimming back quickly. On the river bottom in many rivers, you can see river mussels filtering the river water with their orange gills. Along the river, insects buzz and birds chirp. Swimming fish ducks are a common sight. You may also chance upon otters or beavers.

But in order for us to experience all this wildlife, the riparian vegetation must be in place. Trees, bushes and scrub along the river's edge are crucial for insects, which in turn are vital food for both birds and fish. Riparian vegetation also serves as a home and hiding place for many birds. Trees and shrubs provide important shade in the river when the sun is shining in July. Trees also bind the soil and prevent erosion and sliding of the river bank. Branches and fallen trees in the river serve as hiding places for fish and other animals. Organic material from the riverside vegetation that ends up in the river becomes important food for benthic animals, which in turn are food for young salmon. The benthic animals are not easy to spot, but they are there. Primarily insect larvae, which we also call nymphs, but also worms, snails, mussels, small crustaceans and water mites. They are all worth a study.

Salmon anglers are not always happy about all this marginal vegetation, as it can make fishing difficult. But without riparian vegetation, there will be fewer fish.