RESTORE 3 Upscaling

Integrative Measures for the Restoration of Intact Reef Systems of the European Flat Oyster
Project Duration: 2025–2034

RESTORE 3 is a collaborative restoration project dedicated to the long-term recovery of biogenic reef systems formed by the European flat oyster (Ostrea edulis) in the German North Sea.

The project is delivered through close collaboration between the Federal Agency for Nature Conservation (BfN), the Alfred Wegener Institute (AWI), and the Thünen Institute of Fisheries Ecology Over a ten-year period, existing restoration measures will be further developed, expanded to additional sites, and supported by comprehensive scientific research and monitoring.

The overarching objective is to establish self-sustaining, functional oyster reefs as valuable marine habitats within the German North Sea. By restoring these reef systems, the project aims to enhance biodiversity, strengthen ecosystem functioning, and secure the long-term ecological benefits provided by native European flat oyster reefs.

Why oyster reefs?

Oyster and mussel beds are among the biogenic reef types of temperate regions and are considered some of the most threatened marine habitats worldwide. Centuries of intensive fishing led to the near-complete collapse of natural populations of the European oyster throughout Europe during the 20th century.

Oyster reefs are hotspots of biodiversity:
They provide food, shelter, and settlement substrate, function as spawning and nursery grounds, and stabilise the surrounding ecosystem through their three-dimensional structure. In addition, they improve water quality through filtration, bind sediments, and contribute to increasing the ecological value of the seabed.

Project objectives

RESTORE 3 builds upon the extensive preparatory work and findings of the BfN funded projects RESTORE and PROCEED and also benefits from close collaboration with the Native Oyster Restoration Alliance (NORA). These initiatives have established essential foundations for the active restoration of biogenic reefs — ranging from the identification of suitable restoration sites and monitoring methods to the sustainable production of oyster spat. The project focuses on scaling up proven restoration measures:

• Spatial expansion of existing pilot oyster reefs in Borkum Reef Ground
• Establishment of a pilot oyster reef in Sylt Outer Reef
• Expansion of oyster cultivation and oyster spat production
• Broadening of target species: reintroduction of oysters and stock enhancement of associated species
• Scientific support and monitoring
• Enhancement of ecosystem functions and biodiversity

In addition to the European oyster as a key species, further groups of organisms will also be specifically incorporated. These include mesopredators such as the European lobster (Homarus gammarus), as well as top predators such as Thornback ray (Raja clavata). The aim is to restore stable, functioning reef ecosystems with high biodiversity and essential ecosystem services.

The project activities on reef restoration, species reintroduction, and monitoring are carried out within the Natura 2000 sites Borkum Reef Ground and Sylt Outer Reef and make a substantial contribution to the implementation of management and compensatory measures in marine nature conservation. RESTORE 3 thereby establishes important prerequisites for implementing the EU Nature Restoration Regulation and makes a significant contribution to the long-term restoration of valuable habitats in the German North Sea.