Sardines, anchovies and other fish known as ‘small pelagics’ are very sensitive to the environmental conditions in which they live. For several years now, their abundance and nutritional quality have been declining, with a direct impact on the activities of fishermen and the canning industry. In this context, the DEFIPEL research project, conducted between 2019 and 2023, has made it possible to study the sustainable development issues of the small pelagic sector in France. Numerous actions have been identified to lead to the sustainable management and protection of resources and their fisheries.
By Laurie Henry & Carole Saout-Grit
Cover photo: school of sardines moving in the ocean ©pexels
How can we ensure the sustainability of fishing for certain essential species such as sardines and anchovies, in a context of climate change and fluctuating market demand? It was to answer this question that the DEFIPEL research project (Development of an integrated management approach for the small pelagic sector) was launched in 2019. Supported by Ifremer and funded by France Filière Pêche, it mobilised a consortium of twelve public and private partners* over a period of four years, including research organisations and fishermen’s organisations. The results will soon be presented at the TRANSPEL conference in early April in Brest, with the aim of consolidating the viability of the French small pelagic fish fishery.
Understanding variations in small pelagic fish populations
From the English Channel to the Mediterranean via the Bay of Biscay, small pelagic fish play a crucial role in marine ecosystems and in the fishing economy in France. The sardine (Sardina pilchardus) and the anchovy (Engraulis encrasicolus) are key resources in the food chain, feeding on plankton and serving as food for higher predators such as birds and marine mammals.
But these species are very sensitive to environmental variations. Climate change alters factors such as water temperature and the availability and composition of plankton, with direct consequences for their growth and abundance. In Brittany and the Mediterranean, sardines have become smaller and less fatty due to the decrease in the size and quality of the plankton on which they feed. All these variations also affect the nutritional quality and economic profitability of fishing, raising the question of new strategies for their management.
tinned sardines ©Laark Studio pexels
The DEFIPEL project therefore focused particularly on seasonal and interannual variations in fish populations. These complex and interdependent temporal dynamics are influenced by numerous environmental and biological factors. Seasonal fluctuations – such as the distribution, quality and fat content of fish – and interannual variations – such as the abundance, growth and quality of fish in relation to environmental conditions – directly affect the fishing and processing industries, both of which depend on the quantity and quality of fish available each year.
Annual variations in the average weight of sardines (green), anchovies (red) and sprats (orange) between 2000 and 2022, all ages combined © DEFIPEL
Innovative indicators for balanced population management
In a comprehensive integrated approach, the scientists of the DEFIPEL project used various indicators (ecological, economic, fishing fleet dynamics, etc.) to assess the health of ecosystems and their impact on population fluctuations. Data on mortality rates by type of fishing, or on the critical reproduction thresholds to be respected to limit pressure on fish populations, were also used. Finally, in a context of increased consumer demand for canned fish, economic analyses have made it possible to consider optimising the profitability of fisheries at the same time as their sustainability, in order to adjust fishing practices to the state of fish populations.
Annual trend in national imports of canned sardines, which have been increasing since the 2000s in response to growing consumer demand in a context of a decline in local resources. © DEFIPEL
According to Martin Huret, coordinator of the DEFIPEL project, the biomass of populations remains one of the most revealing indicators of the health of small pelagic fish populations today. ‘This indicator is closely monitored in relation to population management, as it will be the main piece of information taken into account when establishing advice on exploitable quantity. However, recent developments in the size, weight and condition of small pelagics are particularly worrying and are indicative of profound changes within pelagic ecosystems.
All the monitoring indicators produced by DEFIPEL have been grouped together in a dashboard shared by all stakeholders, enabling them to monitor the dynamics of the sector and react to alerts. If the data show, for example, a critical decrease in the average size of fish, seasonal restrictions or catch limitations can be put in place to allow the regeneration of the fish populations concerned. Priority fishing areas can be redefined to avoid overexploiting fragile ecosystems.
This scoreboard is highly appreciated and the players in the sector ‘are attentive to our results and the strategies proposed. The current severe constraints also force them to consider all solutions’, emphasises Martin Huret. The observations of professionals are integrated into it to refine the indicators. The fishermen, who actively participate in the collection of data on fish populations and fishing conditions, thus provide valuable knowledge of local dynamics. This collaborative approach, which also involves processors and maritime space managers, makes it possible to transform scientific data into concrete actions that are in line with everyday realities.
Adaptation scenarios for moving towards sustainable fishing
In order to anticipate the impact of climate change on small pelagic fish, some adaptation scenarios were then drawn up based on digital simulation models. ‘We use a bioenergetic model to simulate the effect of temperature and zooplankton on the growth of sardines and anchovies, and confirm a trend towards their decline in the event of food shortages, explains Martin Huret. This model also emphasises that regions such as the English Channel or the North Sea could offer better conditions in the future. Another simulation model, integrating fleet dynamics and economic constraints, makes it possible to evaluate management scenarios on ecological and economic indicators in the medium term’.
Annual change (in percentage) in the average sardine dependency of French fishing vessels © Defipel
The adaptation paths are moving towards the valorisation of a smaller sardine, or a greater capacity for the valorisation of species such as anchovies, octopus or bluefin tuna (with a current quota limitation in the latter case).
The scientific conclusion is that since the closure of the anchovy fishery from 2005 to 2010, and despite high biomasses since the reopening, the market has been largely lost to France, particularly due to the reduced size of the fish. The low quotas on mackerel and horse mackerel have simultaneously limited the availability of these species, and all fishing fleets have therefore paradoxically become more dependent on a sardine population that is already weakened.
Martin Huret adds: ‘It is true that the availability of different species is a factor of economic stability, we must work on this by diversifying markets and ensuring the good health of all fish populations for better medium-term visibility for fishermen’.
the sardine in gourmet cuisine ©pexels
The DEFIPEL project stands out for its comprehensive approach, taking into account ecological, economic and climatic realities, and could serve as a model for other similar initiatives. ‘DEFIPEL has had the advantage of bringing us much closer to professionals in the sector, fishermen and canners, explains Martin Huret, the acculturation has been a two-way process and this is an asset for the future. We will continue to collaborate on our evaluation campaign, through the expertise carried out each year, and we hope to collaborate on new research projects.
Improving communication with consumers is also one of the many complex issues faced by the small pelagic sector. The consumer has a key role to play in consuming locally, for a better valorisation of French fishery products, thus minimising imports and excessive processing of products. Thanks to its innovations, the DEFIPEL project contributes to the resilience and sustainability of the small pelagic fish sector, while meeting the expectations of marine biodiversity preservation.
The partners of the DEFIPEL project
- Laboratories AMURE/Université de Bretagne Occidentale and LIENSs/Université de la Rochelle
- CNPMEM (National Committee for Sea Fishing and Marine Fish Farming) and CDPMEM 29 (Finistère Departmental Committee for Sea Fishing and Fish Farming)
- PNMI (Iroise National Marine Park)
- FIAC (Federation of Canned Food Industries) and CITPPM (Confederation of the Fishing Industry and Aquaculture)
- Professional Organisations : Pêcheurs de Bretagne, FROM Nord, Vendée et Pêcheurs d’Aquitaine.