More than 15m oysters to be released in the North Sea for UK rewilding project

More than 15m juvenile oysters are to be released into the North Sea in one of the biggest rewilding projects in UK waters.

The scheme, which will use a unique rearing process, hopes to re-establish a huge oyster bed around Orkney that experts say will create a “trophic cascade” of climate and ecological benefits.

Richard Land, the marine expert leading the project, said it would have a knock-on impact on the entire ecosystem. “It won’t just benefit fish and the bay, it will benefit sea mammals, seabirds and the whole environment.”

Experts hope the scheme, which is being run by the Green Britain Foundation, the Nature Restoration Fund, Marine Fund Scotland and North Bay Innovations, will provide a template to revive oyster beds in coastal areas around the UK. “This project is a blueprint for a wider plan to reintroduce oysters to the UK and to European waters,” Land said.

Oyster beds used to be a key part of the UK’s marine ecosystems, covering huge areas of coast – some in the North Sea covered an area the size of Wales. But during the Industrial Revolution, oysters became a popular food source for UK workers – between 1840 and 1850, Londoners alone are estimated to have consumed 700m of the shellfish.

This overfishing, combined with increased pollution, climate change and deliberate removal to clear channels for shipping, has had a devastating impact on oyster populations and interdependent subspecies, triggering what scientists describe as a “negative cascade” that has decimated marine ecosystems.

However, experts believe restoration projects such as the one near Orkney offer the chance to rebuild thriving coastal waters – as well as helping to tackle the climate crisis and improving water quality.

Young oysters are relayed at Scotland’s last wild native oyster fishery in Loch Ryan. Photograph: Jeff J Mitchell/Getty Images

Dale Vince, the founder of the Green Britain Foundation and one of the backers of the scheme, said research suggests oyster reefs can sequester significant amounts of planet-heating CO2. He said this project could see the restoration of about 15m oysters in a new bed covering more than 100 hectares (247 acres) – potentially sequestering up to 76 tonnes of CO2 each year.