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The article examines one research which determines the extent to which wild fish from surrounding waters aggregate around salmon farms across the farming regions in Norway. Wild fishes collected at nine farms and nine control locations were counted on three separate days in June-August 2007. After counting, it was revealed that Gadoid fishes, specifically Pollachius virens, Gadus morhua and Melanogrammus aeglefinus, were dominating farm-associated assemblages. Factors such as a heightened potential for the transfer of pathogens from salmon farms to wildfish as well as the altered availability of wild fish to fisheries are cited as two main reasons behind substantial aggregations of wild fishes at farms.

The article presents a study that determines the farm abundance and spatio-temporal distribution of Pollachius virens in a fjord system with concentrated salmon cage aquaculture in Øksfjord, Northern Norway. It notes on the use of video counting to estimate the abundance of the saithe at various depths, of acoustic transmitters to study its movement in the farms, and of passive listening stations to monitor its spatio-temporal distribution. It reveals the abundance of the saithe in both farms during the release of tagged saithe and discloses its periodic movement from release farm to natural areas. It entails that understanding fish movements can minimise the outbreaks of disease in fish farms and in the populations of wild fish in adjacent areas.