General Fisheries Commission for the Mediterranean - GFCM

Stock assessment

The first step towards achieving the conservation and sustainable use of living marine resources exploited by fishing activities is to gain an understanding of the current status and health of commercial stocks and fisheries. This provides the technical building blocks for the formulation of scientific advice, including forecasts of future status, that guides decision-makers in the determination of the most appropriate management and conservation measures to be included in binding recommendations.

Within the GFCM, stock assessments are performed and evaluated through the Scientific Advisory Committee for Fisheries (SAC) and its Working Groups for Stock Assessment (WGSAs) in the Mediterranean, and of the Working Group on the Black Sea (WGBS) and its Subregional Group on Assessment for the Black Sea (SGSABS) in the Black Sea. All the input and output information from validated stock assessments are summarized in Stock Assessment Forms (SAFs) which are published online every year. Recently, the Stock Assessment Results (STAR) framework has been introduced, comprising a detailed standardized database of all stock assessment results with the aim of streamlining and automating the information flow from stock assessments to scientific advice, strengthening quality assurance and data dissemination and serving as a foundation to provide a variety of quality-controlled data products related to the management of fisheries in the Mediterranean and Black Sea.

The SAFs (and the STAR framework in the future) provide both detailed information on the status of specific stocks (mainly of, but not limited to, GFCM priority species) as well as the basis for the overall assessment of the status of Mediterranean and Black Sea fisheries resources performed every two years under the auspices of The State of Mediterranean and Black Sea Fisheries (FAO, 2021).


  • Performance of regular stock assessments through the WGSAs and SGSABS, with the additional help of external experts when needed, in order to maximize the knowledge-base.
  • Improvement of the quantity and quality of assessments through standardized data collection and quality control, data preparation efforts, benchmark sessions, research programmes, and revision of the framework for the provision of advice.
  • Development and maintenance of the STAR framework standardized database and provision of a variety of quality-controlled data products.
  • Review of the stock assessment methodologies used to provide advice within the GFCM, compiled in the context of the Working Group on Stock Assessment Methodologies (WGM).
  • Study of stock boundaries through ad-hoc projects (e.g. TransBoran).
  • Enhancement of regional capabilities through training and capacity-building activities in stock assessment and related topics (e.g. age reading, training of trainers, joint summer school on stock assessment 2017, 2018).