Overvåkingsprogrammet for Gyrodactylus salaris i settefiskanlegg og elver

In 2025, a total of 2367 specimens of Atlantic salmon from 71 rivers and 2340 specimens of Atlantic salmon and rainbow trout from 71 hatcheries/farms were sampled and examined in the surveillance program for Gyrodactylus salaris. In addidion, five farms rearing rainbow trout and two hatcheries rearing Arctic char, were surveyed using eDNA monitoring. The parasite was not detected in any of these samples.

A total of 54 rivers have so far been confirmed infected since G. salaris was introduced to Norway. As of 31.12.25, G. salaris is confirmed present in six Norwegian river systems in the Drammen infection region. These are the rivers Drammenselva, Lierelva, Sande, Selvikvassdraget, Bergerelva and Ebbestadelva. Treatment of five rivers in the Driva infection region, Batnfjordselva, Driva, Litledalselva, Usma and Gylelva in county Møre og Romsdal, was completed in 2024. These rivers are at present part of the declaration of freedom programme, awaiting confirmation of eradication. Altogether 43 rivers have been declared free after treatment.