15th June: Collaboration uncovers new details of the marine migration of Atlantic salmon

Coordinated efforts into establishing a new online International PIT Tag Database for wild salmon and trout has recorded its first success. A tiny PIT (Passive Integrated Transponder) tag from a wild juvenile salmon released in a French river (Scorff) in April 2022 has been subsequently detected during routine screening at a commercial fish processing plant in Iceland in July 2022. Further investigation revealed the PIT tag was part of a haul from a mackerel fishing vessel some 200km north-east of Iceland on 25th July.

This adds new and important detail to the knowledge base around salmon marine migration and individual pathways. Taking the most likely migration route for this fish suggests that it has been covering an average of around 34km per day whilst in the sea before being recaptured.

This knowledge would not have been possible to obtain without the online database developed by the UK’s Missing Salmon Alliance (MSA) and Norwegian Institute of Marine Research (IMR). It follows coordinated efforts between these partners, the Icelandic Marine and Freshwater Research Institute (MFRI), the Directorate of Fisheries in Iceland, the French National Research Institute for Agriculture Food and Environment (INRAE), the French Observatory of Research on Diadromous Fish in Coastal Rivers (ORE DiaPFC) and the International Council for the Exploration of the Sea (ICES) working group on North Atlantic salmon.