Hedströmmen Bernshammar

Hedströmmen is well visited by anglers from all over the Mälardalen region. There is a local population of trout in Hedströmmen, but the local population is far too small for sport fishing.

To withstand sport fishing, the river is strengthened with support releases. These support releases are offspring from wild-caught parents that have been raised on roe and allowed to hatch at the fish farm in Kloten. So it has been chosen to introduce Catch and release on ALL trout, i.e. that they are re-released.

The trout must increase in number for freshwater pearl mussels to have a go. The mussels spend the first period of their life attached to the trout's gills. There they develop from larvae into small mussels. Without this transformation, there cannot be more mussels. The farmed trout that were previously released for fishing unfortunately do not function as host fish for the mussels. Therefore, a healthy population of local trout with good regeneration is needed.