Abstract
Marine fisheries have a direct impact on the resources they exploit but also indirectly affect other species, habitats and the way ecosystems work. Ecosystem approach to fisheries (EAF) is a major aspect for the exploitation of marine resources and conservation of species. An ecosystem is set formed by a community of living beings and their biological, geological, edaphic, hydrological, climatic environment. Organisms are distributed as patches across a wide continuum of spatiotemporal scales. The marine strategy framework directive (MSFD) proposes an ecosystem approach for the assessment of the marine environment. Bottom-up control of predator fish through small pelagic fish has been noticed in the Benguela and Humboldt Current and in Guinea, since several predator fish suffer when their prey stock collapses. The scientific community needs to set up a long-term scientific strategy in order to enhance its ability to provide suitable competences for the ecosystem approach to marine resources.