Plymouth Sound and Estuaries

Site overview: Plymouth Sound and Estuaries, on the south-west coast of England, is protected because of the sandbanks found here. Eelgrass meadows grow on top of these sandy patches and their long roots help stabilise the seabed. The estuaries here are ria estuaries, which are drowned river valleys. As a result salty water mixes with fresh water creating a unique environment. Rocky reefs in diluted salt water are rare, but they are found here. The extensive mudflats here are also highly productive and provide important feeding grounds for internationally significant numbers of wildfowl. Nationally scarce fan mussels are also found here.

Designation Status
Last Updated
6 June 2017
MPA Type
Special Area of Conservation
MPA Purpose
areas which have been identified as best representing the range and variety within the European Union of habitats and (non-bird) species listed on Annexes I and II to the Directive


50° 21' 59" North,
4° 10' 35" West

Surface Area

63.88 km2
(24.67 mi.2 )


279.52 km
(173.69 mi.)

Iconic features protected by this site


  • Atlantic salt meadows (Atlantic salt meadows (Glauco-Puccinellietalia maritimae))
  • Estuaries
  • Intertidal mudflats and sandflats (Mudflats and sandflats not covered by seawater at low tide)
  • Reefs
  • Subtidal sandbanks (Sandbanks which are slightly covered by sea water all the time)
  • Shallow inlets and bays (Large shallow inlets and bays)


  • Allis shad (Alosa alosa)