Marine Policy, Volume 152
There is an increasing need for marine spatial planning in the North Sea given the multiple uses with competing objectives. Plans to increase renewable energy production by establishing offshore wind farms (OWFs) are likely to coincide with existing and planned marine protected areas (MPAs), with obvious incompatibilities relating to conservation goals. Both will restrict fishing activities to varying degrees, thus a framework is needed to assess possible trade-offs to differing stakeholders and ecosystem health. Using a spatially-explicit trophic model, ecosystem response to different types of spatial closures to fisheries was evaluated using a variety of indicators relating to ecosystem health and fisheries productivity in the southern part of the North Sea. Additionally, hypothetical MPAs designated with specific ecological objectives in mind were tested. Scenario outcomes suggest that closures may need to be accompanied with additional fisheries management measures to avoid unintended negative impacts outside the closed areas. Furthermore, size and placement of spatial closures are important factors influencing overall benefits and losses in terms of ecological health and fisheries yield. One particular hypothetical large-scale closure, designed with the goal of protecting areas with high biodiversity, performed better in terms of indicators and trade-offs than the more fragmented, currently planned and existing closures. Although model outcomes have to be treated with care, the spatially-explicit food web modeling approach will likely aid in providing a more holistic evaluation of trade-offs between conservation objectives and fishing activities, which should contribute to a more target-oriented framework for the evaluation of closed areas.
Miriam Püts, Alexander Kempf, Christian Möllmann, Marc Taylor, Trade-offs between fisheries, offshore wind farms and marine protected areas in the southern North Sea – Winners, losers and effective spatial management, Marine Policy, Volume 152, 2023, 105574, ISSN 0308-597X, https://doi.org/10.1016/j.marpol.2023.105574.
Implementation Context: The Institute of Sea Fisheries works with the Institute of Marine Ecosystems and Fishery Science, Centre for Earth System Research and Sustainability. They work on the topic of spatial management and trade-offs between stakeholders, notably between fishing activities and increased ocean space requirements for offshore wind farms (OWFs), but also conservation measures like marine protected areas (MPAs).
Aspects / Objectives: This study aims at evaluating the efficiency of different types of spatial closures to fisheries using a variety of indicators relating to ecosystem health and fisheries productivity.
Method: The method is based on a modelling software used to evaluate anthropogenic influences on ecosystems called Ecopath with Ecosim (EwE).
Main Outputs / Results: The study shows that fishing exclusions have a positive impact on ecological indicators within closed areas. The assessment shows that an effort to reduce the amount of fishing is needed to counterbalance effects from the redistribution of other efforts. It concludes that the placement and size of an closure is the most important factor, and that closure areas with low fishing efforts and a high protective value performed the best.
Transferability: The study aims at evaluating the efficiency of different types of spatial closures to fisheries using a variety of indicators. It is therefore replicable and transferable to other areas that share similar features.
Responsible Entity: Thünen Institute of Sea Fisheries, Herwigstraße 31, 27572 Bremerhaven, Germany
Costs / Funding Source: This work was conducted within two projects: BioWeb, which received funding from the Federal Ministry of Education and Research (BMBF) / (PTJ) within the framework of KüNO (funding reference: 03F0861B) and SEAwise, which received funding from the European Union's Horizon 2020 research and innovation programme under grant agreement No 101000318. It did not receive any specific grant from funding agencies in the commercial or not-for-profit sectors.
Contact person: Miriam Püts: miriam.puets [at] thuenen.de