Thermolicer. Image: Linn Therese Skaar Hosteland.

Mechanical delousing boom

397 mechanical delousing treatments were reported on Norwegian salmon farms in the last 11 weeks. 

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The figures, obtained by kyst.no from fish health statistics at Barentswatch and from lusedata.no, reveal that in 2016 so far there have been 771 reports of mechanical treatments, of which 363 (47%) have occurred over the last ten weeks.

As farmers report these statistics on a weekly basis, the extent of each mechanical delousing treatment can vary – from a single cage to an entire site.

The percentage of companies using mechanical delousing methods (by week) in Norway.

As the graph above illustrates, 7% of farmers in Norway conducted mechanical delousing last (week 40), and statistics also show that the number of reports has increased steadily week by week, since week 12.

According to statistics, the most mechanical treatments took place in Sor, Trondelag, Nordland and Hordaland.

Updated lice reports from last week show little change from the week before, with all regions of Norway below the prescribed louse limits of an average of under 0.5 adult females per fish.

The number of mechanical treatments, by region, week 30-40.

The counties that are the highest are Nordland, with an average of 0.37 adult females, and Sogn og Fjordane with an average of 0.32. In the rest of the country all the counties averaged less than of 0.2 adult females.