More than 15 million oysters to be released into North Sea for UK rewilding program | Marine Life

In one of the largest rewilding schemes in British waters, more than 15 million juvenile oysters will be released into the North Sea.

The scheme will use a unique farming process to recreate a huge oyster farm around the Orkney Islands, which experts say will create a “trophic cascade” of climate and ecological benefits.

Marine expert Richard Rand, who is leading the project, said this would have a knock-on effect across the entire ecosystem. “Not only will this benefit the fish and the bay, it will also benefit marine mammals, seabirds and the environment as a whole.”

Experts hope the scheme, run by the Green Britain Foundation, Nature Recovery Fund, Sea Grant Scotland and North Bay Innovation, will Restoring oyster beds in coastal areas Across the UK. “This project is a blueprint for a wider plan to reintroduce oysters to British and European waters,” Rand said.

Oyster beds were once an important part of Britain’s marine ecosystem, covering large swathes of the coast – some in the North Sea are the size of Wales. But during the Industrial Revolution, oysters became a popular food source for British workers – between 1840 and 1850, Londoners alone consumed an estimated 700 million shellfish.

This overfishing, combined with increasing pollution, climate change and intentional fishing to clear shipping lanes, has had a devastating impact on oyster populations and interdependent subspecies, setting off what scientists call a “negative cascade” that devastates marine ecosystems.

However, experts believe restoration schemes around Orkney offer an opportunity to rebuild thriving coastal waters and help tackle the climate crisis and improve water quality.

Dale Vince, founder of the Green Britain Foundation and one of the project’s supporters, said: Research Oyster reefs have been shown to sequester large amounts of the carbon dioxide that is causing the planet to heat up. He said the scheme could restore about 15 million oysters in new farms covering more than 100 hectares (247 acres), potentially sequestering up to 76 tonnes of carbon dioxide per year.

But those behind the scheme say the real goal is to stimulate the natural spawning of beds that, once established around a coastline, could increase carbon capture “more than 1,000 times a year over about 15 years”.

Vince added: “This whole project really stems from: How do we let nature capture carbon for us? Restoring native oyster beds is a perfect example of how we can work to restore nature and address the climate crisis at the same time… By reintroducing them, we are bringing life back into the ocean ecosystem, creating important habitat for other marine life, and reducing carbon in the atmosphere. It’s a perfect combination.”

Orkney’s initiative is to grow baby oysters on calcium carbonate-rich “plates”. Once the oysters are grown, the plates are lowered into the sea in long lines, helping them hide from predators until they are large enough to survive and form beds, forming reefs made up of scallops, molluscs, algae, seaweeds and invertebrates, among dozens of other species.

Alistair Carmichael, the Lib Dem MP for Orkney and Shetland, welcomed the plan. “Efforts to restore and rehabilitate the island’s historic wildlife are absolutely welcome,” he said, “especially if accompanied by opportunities for carbon sequestration.

“Orkney has a long and productive history in the oceans around us. It is in all our interests to balance the needs of our waters and seabed so that future generations can benefit.”

Philine Zu Ermgassen of the University of Edinburgh said the reintroduction program was crucial to restoring oyster populations.

“With oyster populations now in such low numbers, they cannot recover in many places without human intervention. It’s exciting that hatchery technology is continuing to evolve to meet the needs of the growing restoration community. This innovation is key to producing enough oysters from local genetic resources to support the recovery and restoration of this extremely valuable ecosystem.”