For some years, marine scientists have tried to keep alive captured bluefin, and the breakthrough came when researchers from the Institute of Marine Research, fishing vessel Vestbris and the Directorate of Fisheries’ vessel Fjordgyn managed to catch and transfer one bluefin tuna from the net to a transport cage.
Since then, the research team has been able to replicate this success with 22 more bluefin tuna caught west of Florø.
‘It’s a privilege to finally succeed! We have learned a lot already. Now we hope to be able to scale up the experiment with a larger catch during,’ said Institute of Marine Research project manager Manu Sistiaga, commenting that being able too keep bluefin alive in cages is a kind of holy grail for the fishery. This is done in the Mediterranean, but under completely different circumstances.
Bluefin are generally difficult to handle quickly enough and the quality can rapidly deteriorate, so live-stocking bluefin solves a number of challenges, as well as making it possible to supply the market in small doses.
‘Now we know that we can achieve a controlled transfer from the seine to the transport cage, and we have documented that the bluefin are doing well in the transport cage, even after two days of being towed to shore,’ Manu Sistiaga said.
‘The cage forms a large, deep pool. We are confident that we can have 50-100 fish in it.’
Once ashore, researchers were able to inspect the cage, the fish and euthanise it in a controlled manner using electricity. Researchers from NOFIMA and the Institute of Marine Research then took a number of samples to find out more about the quality of the meat. The fish was delivered to Domstein Fish in Måløy before being shipped to Oslo to test the market.
‘In the long term, we must also look at how long bluefin can stay in cages, how much feed they need and what temperatures they can withstand. But first we have to improve capture and transfer,’ Manu Sistiaga said.
In addition to providing its vessel and crew, the Directorate of Fisheries is responsible for co-ordinating the project and the contact with ICCAT, the RFMO responsible for tunas in the Atlantic Ocean.
‘ICCAT has strict requirements for catching and reporting bluefin. The regulations are designed for fisheries in the Mediterranean, where the conditions are very different. There they use divers to a large extent, which we do not have opportunities for in Norway,’ said Hermann Pettersen, project manager at the Directorate of Fisheries.
He believes there is a need for some new thinking, while at the same time creating a fishery that is sustainable, controllable and accepted by the other member states of ICCAT.
‘The project shows the importance of good co-operation between administration, industry and research. This year we were lucky to be able to charter Vestbris with an experienced crew,’ Hermann Pettersen said.