Native Oyster success story on the Milford Haven Waterway
After more than a year of careful rearing, thousands of juvenile native oysters have now been returned to the Milford Haven Waterway, marking a major milestone in an ambitious restoration project involving the Pembrokeshire Coast National Park Authority.
Since the project began in late 2023, Bangor University’s School of Ocean Sciences has been nurturing native oyster broodstock collected from Angle Bay and Burton Ferry. These oysters spawned multiple times in controlled conditions, producing hundreds of thousands of larvae. The tiny larvae were then reared until they were ready to settle on to shells, where they mostly remain fixed as they grow. Some scallop shells held as many as 160 individual oyster spat, ranging from 4mm to 10mm in size.
In February, an estimated 200,000 baby oysters were released into the Waterway by students from Paddle West. The team (assisted by Sky the dog, and with rescue cover support from Rudders Boatyard) successfully transported the oysters to their deployment site in shallow water where they were laid by hand.
Once abundant in UK waters, native oyster populations have dramatically declined due to habitat loss, pollution, over-harvesting and disease.
Pembrokeshire Coast National Park Authority Biodiversity Officer, Sarah Mellor, said “This collaborative project is a major step forward for native oyster restoration in Wales. Achieving complex native oyster reefs once again in the Daugleddau may seem a distant dream, but this project has accelerated our learning and made the dream tangible. These oysters will play a vital role in improving water quality, storing carbon and creating habitat for marine life.”
To further support the restoration effort, some of the oyster-covered scallop shells have been placed into oyster hotels at Rudders Boatyard, where they will be closely monitored. Atlantic Edge Oysters will also oversee a selection of the young oysters to assess their growth rates.
The oysters will be tracked as part of the Natur am Byth! Mòr restoration project, delivered by the Marine Conservation Society with assistance from Sue Burton, the Pembrokeshire Marine SAC Officer.
Sue said, “Native oyster restoration needs oyster suppliers and growers, and this project has proved that we can deliver this in Wales with our home-grown native oysters and expertise.”
The project is being delivered in partnership with Bangor University, the Pembrokeshire Marine SAC Officer and Tethys Oysters in Angle Bay. It forms part of the Blue Carbon Strand of the Pembrokeshire Coast National Park Authority’s Wild Coast! Sustainable Landscapes, Sustainable Places Programme, funded by the Welsh Government and co-ordinated by Tirweddau Cymru Landscapes Wales.
The restored oysters will now be closely monitored to assess their survival and growth, helping to inform future restoration efforts and strengthen the long-term recovery of the species in the Milford Haven Waterway.
