Abstract
Marine ecosystems are made vulnerable by climate change but also by overexploitation of certain species like the forage fish which are food for a large proportion of the marine predators, from large fish to marine mammals and birds. IRD scientists and their research partners from the South have recently made major scientific advances concerning the relations between the different components of the marine ecosystems. The results, obtained from ecological field data and models, provide the support for promoting ecosystem-based fisheries management.