Chesil and the Fleet SAC

Status: Designated


Site overview

The Fleet, on the south coast of England, is the largest example of a lagoonal habitat in England. It is surrounded by the fossil shingle of Chesil Beach.  The lagoon is home to two species of eelgrass and three species of tasselweed, including the rare spiral tasselweed.

MPA Type

Special Area of Conservation

Special Areas of Conservation (SACs) are strictly protected sites designated under European legislation. They contribute both to the UK MPA network and set up to protect habitat types and species considered to be most in need of conservation at a European level (excluding birds).

Designation date

1 October 1996

Surface Area

16.36 km2 (6.32 mi.2)


67.39 km (41.87 mi.)

  • Atlantic salt meadows (Glauco-Puccinellietalia maritimae)

    Areas with specially adapted plants found in the upper reaches of saltmarshes that are not always reached by the tide. The habitat is used for grazing, but is also very important for birds.

  • Lagoons (Coastal lagoons)
  • Annual vegetation of drift lines

    Plants that last mostly only for one growing season on fine shingle shorelines that tend to shift and change.

  • Mediterranean and thermo-Atlantic halophilous scrubs (Sarcocornetea fruticosi)

    Scrubby plants that look a lot like Mediterranean vegetation and grow in the uppermost levels of saltmarshes, often where there is a transition from saltmarsh to dunes. 

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Access to the Fleet lagoon is restricted due to the sensitivity of the area, particularly at the far western end of the lagoon. Most of the Seasearch data available is therefore from the southern and eastern areas. The Narrows is an interesting area, subject to very strong tidal flows and with a high density of snakelocks anemones (Anemonia viridis).

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