A conservation project to restore native oysters in the Milford Haven estuary

NRW have developed a conservation project to restore native oysters in the Milford Haven estuary. Ben Wray, Project Lead tells us the story so far.  

“Our native oysters restoration project is the first of its kind in Wales. If it’s a success, it could be used as a plan for bigger and more ambitious projects across Wales.  

"Native oysters were once abundant across Wales. Numbers have fallen to very low levels after years of historic over-exploitation, changes in water quality, and disease. There are now too few in the wild to have new offspring and naturally boost the population. It is not likely the species will recover without some help. 

“We started the project last year to see if conditions in the Milford Haven estuary can allow oysters to survive, grow and reproduce at locations that were once home to oysters in greater abundance. 

“Phase 2 of the project is now complete. "This involved the laying of “cultch”, or clean shell material, which gives the oysters a better chance of survival, and encourages young oysters to settle.  We worked  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). So far, We have put around 25,000 juvenile oysters in the estuary. We will monitor how they progress. 

“We are confident that the project will be a success. The native oyster is a very important species because of its positive impact on the environment.

"Oysters help to make our marine ecosystems resilient, so restoring this species and the habitat around it will be goodfor people and for the wider environment.  Native oysters filter and clean water and provide needed habitats for fish, crustaceans and other species. They lock away carbon through the filtered particles as well as removing nutrients from the water, so they play a vital role towards balancing the effects of climate change.

“The next stages of the project involve monitoring the oysters to see how they are getting on. Over the next couple of years, we will check how they are surviving, growing, and if there is evidence of reproduction and new oyster communities. 

"We will analyse final results by March 2023. If successful, NRW will look to work with other organisations to bring back native oysters across Wales”. 

The native oyster project is funded by WEFO and Welsh Government.