Ecosystem approach to fisheries

Representatives: Nicolas Bez (IRD) et Olivier Maury (IRD)


Marine ecosystems are experiencing major changes (climate, overfishing, loss of biodiversity, pollution), in a context of increasing global demand for food and economic globalization. The extent of changes and the complexity of systems are such that they need to be studied, modeled and predicted in an integrated manner. Since recent years, the exploitation of living marine resources (e.g. fishing) forms part of an ecosystem approach. This approach aims to ensure human activity while maintaining the integrity and resilience of the ecosystem and its services. The productivity of marine resources being dependant on the state of the ecosystem, such an approach requires an integrative vision that considers the dynamics of species - targeted or not by fishing - their trophic interactions, the effects of the physical environment, anthropogenic forcings (direct and indirect) as well as the dynamics of uses, their economic determinants and their governance. Following a logic of exploitation and conservation conciliation, such an integrated approach carries many scientific challenges that this topic intends to take up. This research will be developed in the context of several international authorities such as IPBES (Intergovernmental Science-Policy Platform on Biodiversity and Ecosystem Services) and RFMOs (Regional Fisheries Management Organisations).


  • To characterize and understand the fishermen’s strategies (individual and collective).

  • To observe and quantify the direct and indirect impacts of uses, e.g. catches of target and by-catch species, effects on habitats and ecosystem functioning.

  • To understand and analyze the combined effects of anthropogenic and natural factors.

  • To integrate (summarize) biological, ecological, socio-economic and legal knowledge to establish ecosystem indicators, assess the efficacy of operational tools for the management of human activities (e.g. marine protected areas) and the conservation of marine ecosystems, particularly for expertise purposes.

  • To develop scenarios of the evolution of uses (including governance scenarios) and their impact on marine biodiversity.


  • North-western Mediterranean, the Benguela and Humboldt upwellings and tropical areas of the Indian, Atlantic and Pacific oceans, waters under jurisdiction and beyond.

  • Ships, demersal fleets and fisheries, small and large ocean pelagic fish.

  • Governance and management systems.


  • Data: Data from commercial fisheries (catch, effort, VMS, etc.), scientific campaigns.

  • Modeling: Statistical analysis of spatial and / or temporal data; analysis of systems / governance instruments; (semi-) Markov models; dynamic models of stock assessment and bio-dynamic models; "End to End" modeling; network modeling applied to industries; development of multidimensional indicators.


MARBEC MARine Biodiversity, Exploitation and Conservation, is a research unit which includes the staff of 4 organizations: IRD, IFREMER, UM and CNRS. Its objective is the study of marine biodiversity in lagoon coastal and offshore ecosystems, at different integration levels, molecular, individual, population and community aspects and the way humans use this biodiversity.