Research from salmon in 21 rivers has shown that in at least six rivers, wild salmon have been impacted.
The six rivers that have been found to have genetic differences in wild salmon populations are Vosso, Opo, Lone, Vestre Jakobselv, Figgjo and Berbyelva.
Researchers believe this is due to wild and escaped salmon competing for the same spawning ground.
Escaped salmon of various numbers have been reported in all 21 rivers.
In 15 of the rivers, no genetic variations in wild salmon populations have been found.
Despite high levels of escapees, wild salmon in the rivers of Etneelva and Namsen were seen to be unaffected. Both have large and robust populations of wild salmon.
This is the first time a survey has looked at the impacts of escaped farmed salmon on wild populations across a whole country.
Data from salmon caught 30 years ago was used to determine genetic differences.
AQUANOR: Escaped Farmed Salmon Affect Wild Fish
NORWAY - For the first time it has been scientifically proven that escaped farmed salmon have genetically impacted wild salmon along the entire Norwegian coastline.
