OLAMUR – LARGE SCALE REALISATIONS OF MULTI-USE SCENARIOS WITH LOW-TROPHIC AQUACULTURE
Introduction
OLAMUR Offshore Low Trophic Aquaculture in large Scale Realisation is a large EU Flagship project in the Baltic/North Sea region (2023-2026) of the Mission Ocean and Waters. The project comprises 25 partners in 8 countries, with three major case studies (Figure 1). Since 2025, five Associated Regions have been attached to the project, in ireland, Spain Portugal, Türkie, and Bulgaria, expanding the project´s activity to the Atlantic, the Mediterranean and the Black Sea. The overall aim is to explore and enhance concepts of multi-use of marine space. The purpose of this presentation is to provide a brief overview of the project´s activities many of which will be presented in the session on "offshore and multi-use" at the Aquaculture Europe 2026.
Figure 1. Case studies of the OLAMUR project. Case A and B combines LTA with wind farms, whereas Case C combines LTA with a rainbow trout farm.
Results and tentative conclusions
LTA cultivation experiments with seaweeds and mussels have been carried out in all three case studies, and results are being analysed. In addition to growth yield, analyses of contaminants are being processed. Both the Baltic and the North Sea are charachetised by extensive human activities, shipping, fisheries, and surrounded by populated shores. Especially the Baltic are receiving excess nutrients from waterways draining into the basin. The Baltic, which is only connected to the North Sea through the narrow and shallow Danish straits, is also characterized by low salinity, particularly in the inner parts.
Growth yield of seaweeds were strongly related to local concitions, of which salinity plays a major role. This is in accordance with estimates models published early in the project (Maar et al.2023). In the Estonian case, the seaweed that was cultivated was Ulva sp, which tolerates low salinity much better than the Saccharina sp cultivated at site A and B. With blue mussels, good yields were obtained at all sites.
Stakeholder interviews were carried out involving LTA farmers, wind farmer industry and legislators in the different countries. Legislation is highly variable among European nations, and even among German Länder. Whereas some countries (Estonia) have developed legislation taking into account that LTA may toneutralize excess nutrients from other activities, most countries practice the sector principle, which de facto counteracts multi-use concepts.
LTA farming is at different stages of development. In general shellfish have better developed markets than farmed seweeds. Upscaling is a prerequisite to obtain sustainable industries. Synergies were obtained between the different industries, in particular with vessel operation and with surveillance of the utilized area. The five associated regions are at different stages with respect to development of the multi-use concepts. LTA is carried out in most countries, whereas the Portugese case includes a floating offshore wind farm.
The main conclusion is that large-scale multi-use of area is possible and is an attractive pathway to obtain more area-efficient utilization of European marine area. We have also found it advisable to include the different industries in such a way that multi-use is beneficial for all partners.
Acknowledgments
OLAMUR is funded by the European Union, grant agreement No. 101094065. Views and opinions expressed are however those of the author(s) only and do not necessarily reflect those of the European Union or CINEA. Neither the European Union or the granting authority can be held responsible for them.
References
Maar, M., Holbach, A., Boderskov, T., Thomsen, M., Buck, B.H., Kotta, J., Bruhn A. 2023 Multi-use of offshore wind farms with low-trophic aquaculture can help achieve global sustainability goals. Communication Earth and Environment. 4:447. https://doi.org./10.1038/s43247_023_01116-6.