PSAT tag data from Atlantic bluefin tuna tagged off Norway from 2020 to 2022
Data files
Abstract
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.
https://doi.org/10.5061/dryad.547d7wmg5
This repository contains pop-up satellite archival transmitting (PSAT) tag data (i.e., location, temperature and depth) as well as code used to generate figures and tables in “Atlantic bluefin tuna tagged off Norway show extensive annual migrations, high site-fidelity and dynamic behaviour in the Atlantic & Mediterranean Sea” published by Ferter, Pagniello et al. (2024) in Proceedings of the Royal Society B.
Files
The following files are included:
- META.csv, which contains metadata listed in Table 1 associated with each PSAT tag,
- SSM.csv, which contains daily locations of tagged Atlantic bluefin tuna derived using a Bayesian state space model described in Block et al. (2011), Jonsen et al. (2005), Teo et al. (2004) and Wilson et al. (2015),
- PSAT.csv, which contains temperature and depth timeseries of recovered PSAT tags, and
- CI.zip, which contains 19 .xlsx files with the latitude and longitude coordinates for the 99% confidence intervals for each PSAT tag. These were generated using the R script SSM_99CI_full_NT.R included in this repository.
Description of Variables in Files
META.csv contains the following variables:
- TOPPID: identification number assigned to PSAT tag as part of the Tagging of Pelagic Predators program,
- PSAT: PSAT tag identification number from manufacturer,
- TagginDate: date on which the fish was tagged,
- ReleaseTime: local time at which the fish was released from the tagging vessel (HH:MM 24-hour times),
- TaggingLatitudeN: latitude (deg N) at which the fish was tagged,
- TaggingLongitudeE: longitude (degE) at which the fish was tagged,
- CFL_cm: curved fork length (cm) of the fish at the time of tagging,
- PopUpDate: date on which the tagged popped-up,
- PopUpLatitudeN: latitude (deg N) at which the tagged popped-up,
- PopUpLongitudeE: longitude (deg E) at which the tagged popped-up,
- DeploymentDuration: length of deployment (days),
- Status: status of tag at end of deployment (i.e., transmitted, transmitted - few data, never transmitted or recovered), and
- Reason: reason why tag popped-up (i.e., pin broke, interval, too deep, mortality, tag loss or whale predation).
SSM.csv contains the following variables:
- TOPPID: identification number assigned to PSAT tag as part of the Tagging of Pelagic Predators program,
- Date: date of position estimate,
- Longitude: longitude (deg E) of position estimate,
- Latitude: latitude (deg N) of position estimate,
- Region: hotspot (whose boundaries are defined in the manuscript) in which the position estimate is located (i.e., 0 = Migratory, 1 = Norwegian Exclusive Economic Zone, 2 = Newfoundland Basin, 3 = Canary Islands, 4 = Mediterranean Sea and 5 = West European Basin), and
- Season: season in which the position estimate was made (i.e., 1 = Fall which includes September, October and November, 2 = Winter which includes December, January and February, 3 = Spring which includes March, April and May and 4 = Summer which includes June, July and August).
PSAT.csv contains the following variables:
- TOPPID: identification number assigned to PSAT tag as part of the Tagging of Pelagic Predators program,
- DateTime: date and time of observation,
- Date: date of observation,
- Depth: the depth (m) at which the associated temperature reading was measured,
- LightLevel: light level (no units) measured by the tag,
- Temperature: the temperature (deg C) measured at Depth,
- Longitude: linearly interpolated longitude (deg E) from SSM.csv to match date and time of observation,
- Latitude: linearly interpolated latitude (deg N) from SSM.csv to match date and time of observation,
- Season: season in which the position estimate was made (i.e., 1 = Fall which includes September, October and November, 2 = Winter which includes December, January and February, 3 = Spring which includes March, April and May and 4 = Summer which includes June, July and August),
- Region: hotspot (whose boundaries are defined in the manuscript) in which the position estimate is located (i.e., 0 = Migratory, 1 = Norwegian Exclusive Economic Zone, 2 = Newfoundland Basin, 3 = Canary Islands, 4 = Mediterranean Sea and 5 = West European Basin), and
- DayNight: categorical whether observation was made during the day = 1 or night = 0 based on local sunset and sunrise.
Code
MatLab and R code is included in code.zip to process, analyze and plot the data contained in this repository and to generate the figures and tables from the manuscript. Norway_Tuna.m is the main file which can be run from the 4th cell called “Calculate Environmental Properties” onwards after the data above are loaded into MatLab. Sub-functions listed in Norway_Tuna.m are included as separate .m files. R code was used to generate 99% confidence intervals provided in this repository.