Holding up PIT-tags to demonstrate how small they are. Can you see them?

Publisert 01.11.2018

Workshopping our way through the question of how small salmon we can tag with PIT-tags. An important question in the SeaSalar project - trying to understand the variable marine survival of salmon.

Workshop participants. Photo: Siv Kristin Eikås Hovland, IMR
Workshop participants. Photo: Siv Kristin Eikås Hovland, IMR


Scientists from Norway, Denmark and Sweden were gathered for a workshop on the effects on PIT tagging on Atlantic salmon smolt. The aim is to perform a meta-analysis of the impacts.

Passive Integrated Transponder (PIT) are small tags frequently used in laboratory and field studies, including studies of sea survival of salmon from they leave the rivers as smolts until they return as adults. Ensuring that animal welfare needs are met is important in such tagging studies.

Tagging effects may also bias results, and it is therefore important to understand how to minimize potential tagging effects, particularly size-dependent tagging effects. On the other hand, it may also bias results if only the larger smolts are tagged, so it is important to know how small fish can be tagged.

Knut Wiik Vollset, NORCE, leads the work, and the workshop was hosted by IMR in Bergen.