However, the results also displayed a strong seasonality in habitat size and locations, as well as high year-to-year variations for the potential spawning habitat depending on regional weather conditions. This variability is key to evaluating the pertinence of Marine Protected Areas (or sensitive areas) for this species.
Bluefin tuna is a commercial fish of high market value which has been strongly overexploited for 15 years, especially in the Mediterranean Sea. The largest stock of adults which reproduce in the Mediterranean Sea is now at its lowest on record, around 40% of late 1950s' level.
In the past years the International Commission for the Conservation of Atlantic Tunas (ICCAT) has set lower quotas, established a restricted fishing period and recommended measures to enforce fisheries control. However, there is a need to increase the knowledge about spawning grounds for exploring additional management measures.
The implementation of a habitat-guided management could help identify spawning areas to be partially closed to fishing, thus protecting the spawners and ensuring adequate repopulation. Moreover, by restricting authorised fishing areas, control operations can be better targeted to fight illegal fishing, which is estimated to account for more than one-third of total catches in recent years.
The JRC habitat model can be adapted to other species of commercial interest. Potential habitat maps of fish at basin scale could help to produce more reliable assessments of fish stocks and can contribute to the planning of more efficient and sustainable use of limited maritime space.
|Contact: Berta Duane|
European Commission Joint Research Centre