New NRW conservation project looks to restore native oysters in the Milford Haven estuary

An exciting new conservation project led by Natural Resources Wales (NRW) is investigating the viability of restoring the native oyster.

This pioneering project aims to trial different approaches to restore the environmentally important native oyster and associated habitat.

It is the first native oyster conservation project of its kind in Wales and if successful, could be used as a blueprint for larger scale restoration projects.

Native oysters filter and clean water and provide essential habitats for fish, crustaceans and other species.

They lock away carbon, and filter particles and nutrients from the water, so they play a vital role towards offsetting the effects of climate change.

Oysters help to improve the resilience of our marine ecosystems so restoring these habitats will provide benefits for people and for the wider environment.

Once widespread across Wales, there have been significant declines of oyster habitats over the last century.

Historic over-exploitation, changes in water quality, and disease are likely to have driven this decline.

These factors left too few individuals in the wild to produce new offspring and bring about natural population recovery – it is unlikely the species will recuperate without intervention.

Working with a team of marine scientists and aquaculture experts, including a local oyster farming business (ABPmer, Aquafish Solutions, Aquatic Survey and Monitoring and Atlantic Edge Oysters), NRW have introduced juvenile oysters and clean shell material in a series of trials over several historic oyster grounds.

The areas will be monitored to check that oysters are surviving, growing and if there is evidence of reproduction.

Ben Wray, Project Manager and marine ecologist at NRW said:

“Restoring native oysters and associated habitat in Wales is extremely important. It improves the condition of the surrounding area and it is great for the wider environment which benefits people too. We are very hopeful that the project will be a success – the native oyster is a threatened and declining species. And it’s a main priority for biodiversity restoration in Wales.

“We are using current and former oyster habitats in the Milford Haven waterway to test if it is possible to introduce native oysters to boost the population. So far, we have introduced around 25,000 juvenile oysters in the estuary and we will monitor how they progress. If the project is successful, oysters could be introduced on a larger scale and across additional sites”.

Dr Andrew Woolmer of Atlantic Edge Oysters said:

“We are really pleased to be able to support this important restoration work in the Milford Haven estuary by supplying the native oysters for restocking. It has been challenging, but we have worked hard over the last few years developing new techniques to produce them.

“Native oysters are an important part of the ecosystem, as well as the heritage of the waterway and we are proud to play a part in their recovery.”

Welsh Government and WEFO provided funding for the important conservation project.

Lesley Griffiths, the Minister for the Environment, Energy and Rural Affairs, said:

“I am very pleased we have been able to back this conservation effort at oyster habitats in Wales, which will help improve the health and resilience of our marine ecosystems.

“Our Marine Protected Area (MPA) Network Management Framework sets out how we will continue to improve management and quality at MPAs across Wales over the next five years, playing a vital role in our efforts to improve the resilience of our marine habitats and biodiversity.”

Monitoring the native oyster restoration project will take place over the next two years. Results will be analysed and examined by March 2023.

If successful, NRW will look to work with other organisations to reintroduce native oysters across Wales.