Small but mighty: managing Northeast Atlantic forage fish to sustain marine life

Forage fish are small to medium-sized species that are often found in large aggregations, feeding on plankton and other small aquatic organisms. They play a crucial role in the ocean as a vital link in the food web, supporting marine wildlife, including marine mammals, seabirds, and fish species. However, the management of fisheries targeting these keystone species currently fails to adequately account for the interaction among species throughout the food web, or the ecosystem at large.

In the Northeast Atlantic, notable examples of forage fish species include sandeel, sprat, herring, mackerel, Norway pout, and horse mackerel. Sandeel, for example, occurs in the records of over 60% of all predatory fish diets analysed in this report and plays a vital role in many seabird diets. The abundance and distribution of forage fish stocks tend to fluctuate significantly due to various factors, such as changing ocean temperatures and reproductive success, with fishing pressure exacerbating fluctuations. For instance, fishing amplifies stock variability by reducing stock sizes, thereby compromising stocks’ resilience to environmental changes, including climate change.

In response to the European regulatory framework and international commitments, current fisheries management of fish stocks in the Northeast Atlantic focuses on sustainably maximising the catches of individual fish stocks (i.e. Maximum Sustainable Yield (MSY)). Adopting an Ecosystem-Based Fisheries Management (EBFM) approach, which is also a legal requirement under the regulatory framework, provides a clear opportunity to factor broader ecosystem dynamics into the management of these species, though its practical implementation is still lagging.

Management of forage fish necessitates the availability of comprehensive data, a requirement that is not consistently met in the region. Even among scientifically assessed forage fish stocks, determining their abundance or exploitation rate remains challenging, making them susceptible to inappropriate management decisions. Among the 32 forage fish stocks analysed in this report, only 31% (ten stocks) are identified as being sustainably exploited (F<FMSY); 47% (15 stocks) are deemed to have a healthy size (B>BMSY); and only 16% (five stocks) meet both conditions, in line with MSY management objectives.

Despite this situation, forage fish are of great importance in terms of both volume and value in the European fisheries sector. There is, however, considerable variation among species as regards volume and value of forage fish landings, with herring standing out as contributing the most to volume (632 100 tonnes), while mackerel contributes most to value (€399 million). Most forage fish are caught using demersal trawlers/ seiners (>400 vessels), purse seiners (>400 vessels) and pelagic trawlers (>200 vessels), and their catches are intended for direct human consumption and industrial use (e.g. for fishmeal and fish oil production). The capture of forage fish for non-human consumption has raised questions, given the reliance of wild predators on forage species as a food source.