July 15, 2026 – Germany’s Bundesamt für Naturschutz, the federal agency for nature conservation, helped construct an oyster reef off the island of Sylt as part of efforts to re-establish a local population of the European flat oyster, once widespread across the North Sea and is now functionally extinct there.
The oyster reef of about 100 square meters was created in the spring of 2026 using 80 metric tons of natural stone deposited on the seabed in biodegradable coconut-fibre nets. Some 160,000 juvenile European flat oysters attached to old oyster shells were then secured to the stones in nets, with the stone base protecting them from sand burial and strong currents, the Bundesamt said on July 14.
Oysters are considered important ecosystem engineers, with their reefs supporting “enormous biodiversity,” while their filtering of surrounding seawater as they feed can “significantly” improve water quality, according to the Bundesamt. The juvenile oysters for the reef were sourced from the Helgoland oyster hatchery.
The newly created reef in the Sylt Outer Reef – Eastern German Bight nature reserve is part of the RESTORE III marine conservation project carried out by the Bundesamt with the Alfred Wegener Institute and other partners to restore the European flat oyster to German waters. Sylt is part of the Frisian archipelago off Germany’s northwest coast, and is known for long beaches and the Wadden Sea mudflats.
“The project is an important step on the way to the resettlement of the European flat oyster in the German North Sea,” the Bundesamt said.
German efforts to restore species-rich oyster reefs have been ongoing since 2014, and the project builds on the previous two RESTORE projects, which included a pilot oyster reef in the Borkum Reef Ground nature reserve. As part of the latest installment, the reefs at Sylt as well as Borkum will be further expanded until 2034.
The European flat oyster (Ostrea edulis) once covered large areas of the North Sea seabed but has been considered functionally extinct there since the early 20th century, mainly due to massive overfishing across its European range, according to the Bundesamt.
The three-dimensional reefs created by oysters provide protection, a food source and habitat for “numerous organisms,” and thus are key to the return of other species that have either disappeared or suffered severe declines, such as rays and lobsters, the agency said.