Tagging project expected to contribute to explaining why bluefin tuna has returned to Skagerrak and Kattegat after more than 50 years of absence.
Saturday 9 September 2017, scientists from DTU Aqua (Denmark), SLU (Sweden) and WWF in cooperation with dozens of volunteer recreational fishermen successfully tagged and released 5 bluefin tuna in the Skagerrak. The sizes of the tagged tunas are estimated to be approximately 130-285 kg, making these tunas some of the largest predatory fish in waters in Denmark and Sweden. This is the first time that bluefin tuna have been tagged in Danish and Swedish waters.
The advanced data storage tags will let scientists describe the migration and distribution of bluefin tuna and their geographic origin (e. g., Mediterranean Sea or Gulf of Mexico). The information will help scientists understand why bluefin tuna have re-appeared in Scandinavian waters and can be used to develop and support sustainable fisheries for bluefin tuna in the Atlantic Ocean and Mediteanean Sea.
The day is also historic because it marks the first time since the 1960s that it is allowed to have a fishery for bluefin tuna in these Scandinavian waters. The project has a special permission from the international tuna management agency in the Atlantic (ICCAT: International Commission for the Conservation of Atlantic Tunas) to catch, tag and release 40 bluefin tunas (20 each in Denmark and Sweden).
The project will continue until September 21 and is only possible with the generous support and enthusiasm of anglers in both Denmark and Sweden. The data collected by the tags will be available for scientific interpretation in approximately 1 year.
The project is jointly supported by DTU Aqua, SLU Aqua and WWF, and is coordinated by DTU Aqua.
Swedish fishermen and a tagging expert from AZTI-Tecnalia (Spain) celebrating the first tagged and released bluefin tuna in Swedish waters, September 9, 2017. Photo credit: Markus Lundgren.
Photo at the top: Scientists from DTU Aqua and a tagging expert from Spain applying a data storage tag to a bluefin tuna (258 kg) in the Skagerrak, 9 September 2017. Photo credit: Lars Norman Hestbæk, WWF Denmark.