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No. 362: Identification of possible protected marine areas in the North Sea, the Skagerrak and the Baltic Sea around Bornholm

Göke, C., Christensen, A., Tonetta, D., Petersen, I.K., Olsen, O., Dahl, K. og Sveegaard, S. 2019. Identifikation af mulige beskyttede havområder i Nordsøen, Skagerrak og Østersøen omkring Bornholm. Aarhus Universitet, DCE – Nationalt Center for Miljø og Energi, 78 s. - Videnskabelig rapport nr. 362. http://dce2.au.dk/pub/SR362.pdf


The project has identified potential marine protected areas (MPAs) in the North Sea, Skagerrak and the sea around Bornholm in the Baltic. The work is commissioned by the Ministry of Environment and Food in Denmark. The outcome is expected to form the scientific background for a decision to designate MPAs as part of the implementation of the Marine strategy Framework Directive.  The work builds on a previous study published by Edelvang et al. (2017a and b).

In the task description prepared by the Ministry of Environment and Food, the analyses should be based on selected EUNIS broad scale habitat types and include a number of specified species of which some are on the OSPAR and HELCOM red lists. The suggestions for MPAs should not exceed 40% of the area and protect at least 40% of the habitats and species in the two analysis areas North Sea together with Skagerrak area and in the Baltic Sea around Bornholm.

The knowledge about the distribution of benthic communities and about a number of the redlisted species is poor for the Danish areas in the North Sea, Skagerrak and the Baltic Sea around Bornholm. Knowledge of how existing communities can develop under protected conditions is similarly lacking. Finally, climate change impact is expected in the future due to increasing temperature and raising sea level.

Having the rather poor data situation in mind especially for invertebrates, a major focus in this project has been to identify potential MPAs that are part of an international network with high coherence. This is to promote the overall objective of the European Union to create a coherent network of marine protected areas. This means that the proposal emphazises 1) representativeness of protected features based on the level of knowledge that exists today, 2) the protected elements have a certain size (sufficiency), 3) a high degree of exchange of organisms that passively move with water currents between the suggested areas (connectivity).  Furthermore, it is recommended that replicability is considered when the final selection of protected areas is carried out by the government.

The major part of the proposed areas are identified using the Marxan program. In total 14 areas in the North Sea-Skagerrak were identified and 12 in the Baltic Sea around Bornholm. The larger proposed areas were subdivided into smaller units. An evaluation of the Marxan proposal including additional data resulted in suggestion of an additional area in the South-Eastern part of the North Sea to include an important area for red-throated divers. In the Baltic, two areas were included, one covering long-tailed ducks and another one covering  shallow sandy seabed’s south of Bornholm where eelgrass is present or can occur.

The analysis is based on available data and only one-year’s data have been used for connectivity analysis