Pelagic Picture #2 – Scientifically sound stock management

Pelagic Fisheries

Scientifically sound stock management

Each year, independent fisheries scientists advise on how much fish can be fished sustainably. Managers (the national administrations, Brussels and Coastal States) use this scientific advice as a basis to determine how much can be fished: the Total Allowable Catch (TAC) for each stock for the next calendar year. This fisheries advice is the cornerstone of sustainable fisheries management.

The basis of the advice is the use of the MSY principle: MSY stands for Maximum Sustainable Yield, and can be understood as the largest long-term average catch or yield that can be taken from a stock under prevailing ecological and environmental conditions. Key in MSY based management is to set fishing mortality at or below the fishing mortality that leads to MSY (i.e. FMSY) and ensure total stock biomass is at or above BMSY. Scientists furthermore include other elements in their assessments so that the advice takes an ecosystem-based approach that contributes to the conservation of marine biodiversity.


For this year, ICES advised in increase of catches of almost 32% for North Sea herring. North Sea herring is well above BMSY and below FMSY since the mid-90s. It is also good news that both the spawning biomass and recruitment in 2022 are now estimated to be significantly larger (87.3% and 32.6% respectively).

Healthy fish stocks are not only essential for the environment but also for the fishing industry’s long-term economic viability. For fishers, the ocean and fishing is one of the most important things in life. They want to pass on this passion to future generations, so that they also can fish for food and can benefit from the sea as a source of work and income.

Science is the basis of PFA members’ sustainable fishing activities. We support fisheries science through our own high-quality, pioneering research programme. Fishers, by nature, have a first-hand understanding of fish stocks and, in collaboration with scientists, can share this insight for the benefit of scientific research.

Vessels of PFA members actively participate in data collection on the pelagic stocks they fish, and this data, information and knowledge contributes to audits, evaluations and reports that are important to maintaining a sustainable fishery for pelagic fish stocks.

PFA Chief Science Officer Niels Hintzen about the scientific approach of fish stocks and fisheries management

“With the help of the self-sampling on-board of the PFA vessels, where we measure over 250.000 fish annually for stock assessment purposes. Therfore, we can estimate with far more precision fishing mortality and stock size, but also gain understanding in the seasonal migration and hence overlap of herring and other pelagic stocks with other parts of the ecosystem such as predatory fish, mammals and seabirds.

With the help of all the crew on-board he fishing vessels we support a data-driven approach to the ecosystem approach in fisheries management.”


Read more about our fishing activities in the Channel the coming weeks: PFA members start herring fishing that is key to food security – Pelagic Freezer Trawler Association (

Date Posted: 4th December 2023