05.07.2021

new findings: Salmon migrate longer distances At Sea

Pop up tagged Kelt

photo above: Salmon Kelt (Salmon after spawning returning to the Sea) equipped with a Popup-Tag  - photo: Audun Rikardsen audunrikardsen.com 

A current scientific study shows that Atlantic Salmon migrate longer distances at Sea than assumed so far. 204 Salmon from Norway, Denmark, Ireland, Spain and Greenland have been equipped with so called "Popup-Tag's" after spawning in the period from 2008 to 2014. These tags record the migration route of the fish and detach from the fish after a certain time. After surfacing they send the recorded data to a satellite.  148 individual fish that were tagged in this way delivered data for the study.

 

Verteilungskarte

grafic above: Migration Routes of different Salmon stocks in the Atlantic - Source: Redefining the oceanic distribution of Atlantic salmon | Scientific Reports (nature.com)j

While Spanish and Irish Salmon moved to rather southernly areas of the Atlantic the Salmon of Danish Rivers swam up to Greenland and even further North in the vicinity of Barents Sea. There are areas at the east coast of Greenland where different stocks swim together at certain seasons (mixed stocks).

Further interesting information about individual migrations, seasonal migrations and climatic influencing factors can be found here:  Redefining the oceanic distribution of Atlantic salmon | Scientific Reports (nature.com)

The technique being used for this complex exploration described vividly in the following graphics: 

overview 

 

Source: (2) (PDF) The Use of Electronic Tags in Fish Research–An Overview of Fish Telemetry Methods (researchgate.net)