PSAT tag data from Atlantic bluefin tuna tagged off Norway from 2020 to 2022

Atlantic bluefin tuna (ABFT; Thunnus thynnus) is a highly migratory
species. To investigate the migrations and vertical behaviours of ABFT
migrating to Nordic waters, we deployed pop-up satellite archival
transmitting tags on 25 ABFT off Norway (Curved Fork Length: 228-292 cm).
We obtained 16 full-year migrations, which differed between individuals,
and physically recovered 13 tags, which provided 4,699 days of archival
depth and temperature data. ABFT occupied waters from the Arctic Circle to
as far south as Cabo Verde, Africa, and occupied depths down to 1190 m and
temperatures from 0.5 to 27.8 °C. During their annual migrations, ABFT
spent, on average, 68 days in Norwegian waters, 65 days in the
Newfoundland Basin, 35 days around the Canary Islands and 33 days in the
West European Basin. Most ABFT entered the Mediterranean Sea with a mean
entry date of May 13th and visited known spawning grounds, staying, on
average, 44 days. All ABFT with full-year deployments returned to
Norwegian waters. ABFT displayed high site-fidelity and dynamic vertical
diving behaviours that varied between hotspots and seasons. These
spatiotemporal data provide important ecological knowledge for sustainable
management and the conservation of the recently recovered eastern ABFT
stock.