New contribution of operational oceanography to the Albacore tuna study and assessment

Researchers from SOCIB, IEO and NOAA published the results of a multidisciplinary investigation on Albacore tuna (Thunnus alalunga) in the Western Mediterranean, integrating information on the reproductive ecology, local mesoscale oceanography and early life dynamics. This study analyses the spatial distribution of adult individuals during the spawning season and proposes a method to evaluate the larval abundances of this species as proxy for the abundance of mature adults in the area.

The results show the importance of the spawning grounds located in the Balearic Sea, identified from the spatial distribution of the fisheries captures, and provides a new larval index informing on the temporal evolution on larval abundances from ichthyoplankton surveys. The larval index developed show a decreasing trend in abundances supporting other abundance indices in the Mediterranean obtained from the fishing activity. Albacore larval abundances can only be tracked accurately if the local mesoscale oceanography is considered and the adequate spawning and larval habitats are identified.
Monitoring larval abundances informs about the population dynamics, providing a unique source of information to assess the trends of the adult population. This information is incorporated in to the evaluation of the exploited stocks, improving the fisheries assessment and management carried on by the International Commission for the Conservation of Atlantic Tunas (ICCAT). These results were presented at the last meeting of the albacore group of the Standing Committee on Research and Statistics (ICCAT) to provide the larval index as indicator of the population trends.

This work has been carried out within the framework of the BLUEFIN TUNA project (funded by SOCIB and IEO), data was also provided by the projects ATAME (2011-29525-004-02), funded by the Spanish Ministry of Science and Innovation and the TUNIBAL project (REN 2003-01176). Additional funding was provided by the European Union’s Horizon 2020 research and innovation program under the Grant Agreement No 773713 (PANDORA). This project has been co-funded by the EU through the European Maritime and Fisheries Fund (EMFF) within the National Program of collection, management and use of data in the fisheries sector and support for scientific advice regarding the Common Fisheries Policy.


Alvarez-Berastegui, D., Saber, S., Ingram, G.W., Díaz-Barroso, L., Reglero, P., Macías, D., García-Barcelona, S., de Urbina, J.O., Tintoré, J., Alemany, F. Integrating reproductive ecology, early life dynamics and mesoscale oceanography to improve albacore tuna assessment in the Western Mediterranean, Fisheries Research, Volume 208, p. 329-338.