The Solent Seascape Project has built a new native oyster habitat in Chichester Harbour, supported by Chichester Harbour Conservancy and the Manor of Bosham. The “oyster restoration zone” (sometimes referred to as a reef) is located in the Chichester Channel.
Why is the new habitat being built?
A threatened species:
Native oysters were once prolific in Chichester Harbour, supporting a thriving fishing industry and marine life. At the peak of the industry during the 19th century more than 3 million oysters a year were landed into Emsworth. But due to factors including overfishing, invasive species, disease and water quality, they have declined by 96% in Chichester Harbour.
Oyster power:
Native oysters are a key part of a productive coastal/marine ecosystem, with benefits including:
- Improving water quality – a single adult native oyster can filter up to 200 litres of water every day!
- Habitats for other marine life. A native oyster reef supports a plethora of other marine species, from small fish and seahorses to marine plants, anemones, seaweeds and crustaceans.
- They remove nitrogen from the water and sequester carbon.
- A native oyster reef provides connectivity between harbour habitats as well as supporting local economies.
How was the new habitat created?
- A thin layer of gravel substrate and a shell , or “cultch” was laid on the seabed and left to settle for a short time with tidal movements.
- 20,000 native oysters were then brought in from Wales. 300 volunteers spent a week cleaning them for biosecurity (oyster scrubbing).
- The native oysters were then laid in the oyster restoration zone.
Watch the videos to find out more:
What will it look like?
The Solent Seascape Project has already built a native oyster reef on the River Hamble, started in 2023. In 2025 the Royal Navy got involved monitoring the reef with UUVs; the imagery showed that even in the first two years, the project had been a great success making a huge difference to life on the seabed in the restoration zone. Watch the project film and see the images from the seabed.
What about harbour users?
The oyster habitat is very shallow – averaging 20cm, and no more than 50cm from the seabed, so it does not present a hazard to navigation.
No Anchor Zone
To protect the oysters and the seabed and to promote the healthy development of the habitat, the area is a No Anchor Zone. There has been extensive liaison with local sailing clubs who use the area for racing.
Marker Buoys
Four new special marker buoys indicate the northern edge of this zone (as depicted on the chart here).
What next?
The newly laid habitat forms an environment that will allow oyster larvae to settle and colonise it, providing the next generation of native oysters to the area.
Further phases of the project will take place over the next two years with each phase coving 1 – 1.3ha. There will also be extensive monitoring of the new habitat and surrounding area to assess its success as well as the benefits to other connected wildlife and ecosystems.
Get Involved
With further phases planned and oyster top-ups, there will be many opportunities to get involved with the project and participate in biosecurity. Follow our social media and sign up to our monthly newsletter to be notified of opportunities.
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The Solent Seascape Project is funded by East Head Impact and the Endangered Landscapes and Seascapes Programme (managed by the Cambridge Conservation Initiative in partnership with Arcadia.)