Several dams were constructed to this river 70 years ago, and salmon could no longer swim up the river to spawn. Now humans have removed dams and built fish passages.
Salmon can run up again!
Help salmon find their spawning ground!
At the same time you also help freshwater pearl mussels.
Freshwater pearl mussels can live very long, over 200 years, but they cannot reproduce without the help of salmon.
The mussel larvae live in the gills of young salmon to survive their first year. After that they set loose and dig themselves in the bottom gravel of the river. The larvae don’t harm the salmon. Part of the mussels are specialized in attaching to salmon juveniles, while the rest prefer trout. Those specialized in salmon can only reproduce with them.
Another awesome reason why salmon are so important!
When the salmon spawn, the female salmon meet with the male salmon and create offspring. With its tail the female salmon digs a hollow in the riverbed. This hole is called a redd. She lays her eggs in the redd, and the male salmon follows and drops his roe in. When the eggs and the roe combine, tiny fish babies start to emerge inside the eggs.
Lifecycle of the freshwater pearl mussel
The mussels in this picture use trout youngsters as their temporary host. The salmon younglings look a bit different.
Learn more about dam removal and migrating fish:
World Fish Migration Day