The total level was the same for 2011 as for 2010, but the mixing of escaped farmed salmon with wild salmon in the most important rivers is still too high, according to a survey by the Norwegian Institute for Nature Research (NINA), conducted on behalf of the Fisheries Directorate and the Directorate for Nature Management.
The numbers of escaped farmed salmon in autumn 2011 was calculated for a total of 36 rivers with a sample size of at least 20 salmon per river.
Escaped farmed salmon were identified on the basis of the growth pattern, with 2461 samples analyzed.
The average performances (not weight) of farmed salmon in the survey was 12.8 per cent in 2011, which corresponds to the same level as in 2010 (13.1 per cent).
The survey showed however that there was a difference between the rivers north and south of Stad.
The proportion of the rivers south of Stad were significantly lower in 2011 than in three of the five preceding years. North of Stad, the percentage was higher in 2011 than in 2010.
The Directorate of Fisheries is working actively in measures to reduce escapes from fish farms.
There will be some time before a reduction in the number of escapes will be calculated in the rivers.
