UK’s largest oyster reef restoration milestone reached as 260 volunteers prepared 20,000 oysters for the Solent - University of Portsmouth

The University of Portsmouth last welcomed hundreds of volunteers to its Institute of Marine Sciences to help prepare 20,000 native oysters to be rehomed

The University of Portsmouth last week welcomed hundreds of volunteers to its Institute of Marine Sciences (IMS) to help prepare 20,000 native oysters for deployment onto a new reef in Chichester Harbour - marking a major milestone in the UK’s largest subtidal oyster reef restoration project.

Between 11–15 May, around 260 volunteers gathered in Portsmouth for a series of “biosecurity days”, carefully cleaning and checking oysters before their release onto the newly constructed reef. The oysters were deployed in Chichester Harbour by Blue Marine Foundation at the end of the week, representing a significant step in restoring one of the Solent’s most threatened marine habitats.

The work forms part of the Solent Seascape Project, a marine restoration initiative led by ocean conservation charity Blue Marine Foundation in partnership with Chichester Harbour Conservancy and the University of Portsmouth’s Institute of Marine Sciences. The project is supported by the seabed owner, the Manor of Bosham.

Native oyster populations in the Solent have declined by around 96 per cent over the past century, driven by overfishing, disease, invasive species and declining water quality. Yet oysters remain one of the marine environment’s most important “ecosystem engineers”: a single oyster can filter up to 200 litres of water a day, while oyster reefs provide habitat for hundreds of marine species and help protect coastlines from erosion.