Britain deploys concrete reef cubes and shells to revive native oysters

Twenty engineered reef cubes loaded with adult and juvenile native oysters and about 44 US tons of recycled scallop shells were placed on the North Sea floor to help restore the European oyster Ostrea edulis.

In the North Sea, Britain has lowered a set of 20 specially designed reef cubes, together weighing about 132 US tons, to create a habitat for the severely depleted native oyster Ostrea edulis. The structures, made from a carbon-neutral material called Marine Crete, feature ridges and openings that allow oysters to attach and provide shelter for fish, lobsters and other invertebrates. Volunteers fixed 4,000 adult oysters onto the cubes, added more than 35,000 juveniles, and scattered roughly 44 US tons of reclaimed scallop shells about 1.1 miles offshore.

The project follows a 2023 deployment that lost material in severe weather, prompting the use of heavier cubes as anchors. Monitoring will assess whether the oysters survive, reproduce and attract broader marine life, potentially reestablishing a self-sustaining reef ecosystem. Celine Gamble, manager of the Wild Oysters Project, highlighted the oysters' role in filtering water and improving coastal health.