Samenvatting

This thesis provides an answer to the question if the International Council for the Exploration of the Sea (ICES) does fulfil its own objective of supporting Ecosystem-based management by producing Ecosystem Overviews as advice. Against the background of ongoing changes and pressures on the ecosystem, management requires a knowledge base for decision making that is tangible and immediate. The extent to which Ecosystem Overviews, as one of many ICES advice products, have been applied in practice has remained unclear in the past. In this study, a mixed methods approach was chosen, analysing the following topics through desk research: ICES objective of supporting Ecosystem-based management by producing Ecosystem overviews as advice, their understanding of the role of Ecosystem Overviews, how Ecosystem-based management is understood and implemented, and if the product is referenced to by actors in the Celtic Seas and Central Arctic Ocean ecoregions, the case study regions of this study. In addition to that, a self-prepared survey was carried out and assessed, next to an existing survey by ICES, shared during two meetings with ICES clients and observers (MIRIA and MIACO) in early 2021. As last step, an interview was held with an expert on Ecosystem Overviews, engaged in the development, and with experience, in the Celtic Seas ecoregion. From all steps, it became clear that the understanding of the role of Ecosystem Overviews often differs between ICES and external parties. For example, several external actors underlined the necessity of a precise knowledge base, enabling the opportunity for the product to be used widely. However, the majority of participants from the self-prepared survey indicated that they do not consider Ecosystem Overviews operational nor easy to use in their field of work. Limited dissemination and promotion was further underlined by survey participants and the interviewee, combined with a recommendation for broadening of the target audience. Ecosystem Overviews contain an enormous potential in informing about the ecosystem, its state and capacity. They have evolved greatly over the last decade, with many adaptions still to come. Especially in the complex quilt of shared authorities and responsibilities in marine management, Ecosystem Overviews have the potential to serve as the knowledge base that is so often requested by different actors in the field. However, changes such as adapting to current pressures on the ecosystem, using a short and precise structure, being tangible and immediate advice as well as better promoting are needed to sufficiently fulfil the ICES objective of supporting EBM in ICES ecoregions, eventually leading to Ecosystem Overviews playing a crucial role in future marine management.