Marine strategy directive and ecosystem-based approach to fisheries: assessment of a reference state of the Bay of Biscay ecosystem
Pascal Lorance, Marie-Joëlle Rochet, Anik Brind'Amour, Verena M. Trenkel

Ifremer, rue de l'Île d'Yeu, BP 21105, 44311 Nantes Cedex 03

The ecosystem-based approach to fisheries management and more recently the European Marine Strategy Framework Directive require assessing the state of an ecosystem to be able to determine suitable management strategies. For assessing the state of Bay of Biscay ecosystem in the early 1990s, an inventory of its environmental features and ecological components was made and the qualitative descriptors from the Marine Strategy Framework Directive were used to assess the environmental status of each component. The assessment was carried out at the level of 19 main ecosystem components. A description of the biological, physical and chemical ecosystem components as well as the human activities putting pressures on them was made. Three ecosystem components (exploited species, sensitive fish species and marine mammals) were further assessed by species (a total of 105 species were considered). Overall the 19 ecosystem components were modified on a regional or local scale by marine and terrestrial human activities. A fuzzy logic based method was used to combine the status assessments of individual components, leading to the conclusion that the Bay of Biscay was most likely impacted in the early 1990s. Finally, for each ecosystem component management issues for moving towards a good environmental status are derived.

Keywords: reference state, ecosystem assessment, management, human pressure, Marine strategy directive, inventory.