Abstract
<title>Abstract</title> <p>Worldwide and across ecosystem types, national and international conservation and restoration efforts are increased to address and mitigate the challenges of the anthropocene. In marine environments, the restoration of oyster reef habitats has gained momentum since the end of the past century. But restoration trials of offshore oyster habitats, such as the historical offshore oyster grounds in the German Bight, are relatively new. Aiming at ecosystem functions such as habitat structure and biodiversity, we present the associated community and development of a restored European flat oyster reef in the nature conservation area Borkum Reef Ground, North Sea. Monitoring with seabed image transects along five years since reef construction showed a small-scale but steady development of an oyster population from year two onwards, while the local benthic community showed a strong development in terms of species richness and abundance. This early developed reef represents the first successes of initiating recovery by active restoration measures in marine offshore habitats in Europe. Our study highlights the potential of ecological restoration for MPA management to enhance the recovery of ecosystem functions, and its value for designated compensation measures for offshore interventions.</p>