A large-scale mackerel egg survey is carried out every three years in the Atlantic Ocean to measure the size of the mackerel spawning biomass.
The results are used by ICES to produce annual stock estimates and catch advice, according to information published by the Pelagic Freezer Trawler Association (PFA).
The survey is conducted by Wageningen Marine Research (WMR) in cooperation with other European research bodies and the pelagic fishing sector. The work combines research vessel surveys with data collected at sea by fishing vessels.
Industry vessels add key data
The PFA says its members support the survey through a self-sampling programme on board all vessels. In addition, the PFA research team conducts subject-specific research projects in collaboration with scientific institutes.
One key task is the collection of spawning female mackerel. These fish are often hard for research vessels to target, as survey vessels focus mainly on eggs in the water. Samples taken by fishing vessels are later processed in laboratories.
Data used for stock advice
ICES, the International Council for the Exploration of the Sea, uses the egg survey data as part of its annual assessment of the mackerel stock. These assessments form the basis for official catch advice.
According to the PFA, closer cooperation between scientists and the fishing sector improves both the completeness and the quality of information on pelagic fish stocks.
Linking science and fishing
The PFA research team acts as a link between researchers and the fishing industry. The aim is to ensure that data collected at sea directly contribute to scientific knowledge of pelagic stocks, including mackerel.
The infographic, published on 27 January 2026, focuses on how joint work between science and industry supports long-term stock assessment and management.