The trials will investigate methods for the development of oyster reefs at offshore locations. A a total of eight reef structures with oysters will be installed underwater within the Borssele Wind Farm Site V.
The Borssele Wind Farm Site V, located 2 km off the coast of the Netherlands, has been designated as an innovation site. The Two Towers consortium of Van Oord, Investri Offshore and Green Giraffe has been awarded the concession and has been given the opportunity to test and demonstrate advanced technologies. One of the technologies is the Ecofriendly scour (Ecoscour) protection.
Oyster reefs are the basis for a healthy, thriving underwater life, said Van Oord. They filter the seawater and provide food, shelter, and spawning area for fishes and other marine species. Over a century ago, a fifth of the Dutch part of the North Sea was covered with European flat oyster beds, but these have disappeared, due to overfishing, habitat destruction and disease.
Areas with undisturbed seafloor are now increasing because of the designation of marine protected areas and the construction of offshore wind farms. This provides an opportunity for restoring the oyster reefs in the North Sea, said Van Oord. It is working with Wageningen Marine Research, HZ University of Applied Sciences, Bureau Waardenburg and the Netherlands Institute for Sea Research.
The offshore Borssele Wind Farm Site V provides an opportunity to gain knowledge on best practices for oyster reef development. The research programme is testing different outplacement methods for live European flat oysters on the two types of scour protection within the site, by installing eight different structures offshore.
Oysters will be placed in various ways such as contained, loose and pre settled. This is being done to determine which method works best for the long-term establishment of oyster reefs on scour protection. In addition, the research team wants to gain knowledge about what the most effective life stage of a European flat oyster is for installation on the scour protection.
Over the past two years, several experiments have been executed, for example to learn about the type of substrate most likely to be successful in collecting oyster spat. The research findings provide insights that contribute to scaling up the development of oyster reefs in existing and future offshore wind farms.