Severn Estuary - Conservation and SSSI Status

Conservation and SSSI Status

The tidal range results in the estuary having one of the most extensive intertidal wildlife habitats in the UK, comprising mudflats, sandflats, rocky platforms and islands. These form a basis for plant and animal communities typical of extreme physical conditions of liquid mud and tide-swept sand and rock. The estuary is recognised as a wetland area of international importance and is designated as a Ramsar site. The estuary is recognised as a Special Protection Area (SPA) under the EC Directive on the conservation of Wild Birds. The estuary is recognised as a Special Area of Conservation (SAC) under the EU Habitats Directive.

Parts of the estuary have also been designated a Site of Special Scientific Interest. The SSSI includes most of the foreshore upstream from Cardiff and Brean Down and most of the upper estuary as far as Sharpness. The Upper Severn Estuary SSSI covers the tidal river between Purton and Frampton on Severn.

The Severn Estuary SSSI original designation involves the English counties of Somerset, Avon (affected by later boundary changes) and Gloucestershire. It involves the Welsh counties of Gwent and South Glamorgan. The Severn Estuary SSSI designation overlaps individual site designations for separate sites in Avon (Spring Cove Cliffs, Middle Hope, Portishead Pier to Black Nore, Aust Cliff), Gloucestershire (Purton Passage) and South Glamorgan (Penarth Coast). The 1976 designation includes two sites previously notified in 1952 (Brean Down and Uphill Cliff). The SSSI forms the major part of a larger area which includes the Taf/Ely Estuary and Bridgwater Bay (as well as the Upper Severn Estuary)

The Upper Severn Estuary SSSI designation involves the English county of Gloucestershire. The site (Severn Estuary and Upper Severn Estuary) is listed in the 'Forest of Dean Local Plan Review' as a Key Wildlife Site (KWS).

Both SSSI citations provide detail of the geological and biological interest and of particular note is the international importance for wintering and wading birds of passage, and of estuarine habits of outstanding ornithological significance. It is stated that the estuary supports over 10% of the British wintering population and is the single most important wintering ground for Dunlin, and for significant numbers of Bewick's Swans, European White-fronted Geese and Wigeon. Nationally important wintering populations are supported such as Gadwall, Shoveler and Pochard.

There are notably seven species of migratory fish which pass through the estuary in both directions. These include significant numbers of Atlantic Salmon and Common Eel.