Site of Special Scientific Interest
A Site of Special Scientific Interest (SSSI) in Great Britain or an Area of Special Scientific Interest (ASSI) in the Isle of Man and Northern Ireland is a conservation designation denoting a protected area in the United Kingdom and Isle of ...
(SSSI) in
Essex
Essex () is a county in the East of England. One of the home counties, it borders Suffolk and Cambridgeshire to the north, the North Sea to the east, Hertfordshire to the west, Kent across the estuary of the River Thames to the south, and G ...
. It consists of mudflats, salt marshes, scrub and wild grassland, and includes the
Southend-on-Sea
Southend-on-Sea (), commonly referred to as Southend (), is a coastal city and unitary authority area with borough status in southeastern Essex, England. It lies on the north side of the Thames Estuary, east of central London. It is bordered ...
foreshore. It has been so recognised for its biological (including ecological) value, rather than geological. A definition five percent larger forms the Benfleet and Southend Marshes
Ramsar site
A Ramsar site is a wetland site designated to be of international importance under the Ramsar Convention,8 ha (O)
*** Permanent 8 ha (P)
*** Seasonal Intermittent < 8 ha(Ts)
**
Special Protection Area
A Special Protection Area (SPA) is a designation under the European Union Directive on the Conservation of Wild Birds. Under the Directive, Member States of the European Union (EU) have a duty to safeguard the habitats of migratory birds and cert ...
. In the centre-west, more than ten percent of the Site is the Leigh National Nature Reserve (NNR), which has been appraised in detail in ''A Nature Conservation Review'' as a site of national importance. The SSSI and NNR include the eastern half of
Two Tree Island
Two Tree Island is a small island lying north-east of Canvey Island and south-west of Leigh-on-Sea in Essex, England. It covers and is connected to the mainland at Leigh by a single span bridge.
The island was reclaimed from the Thames Estuar ...
, in
Leigh on Sea
Leigh-on-Sea (), commonly referred to simply as Leigh, is a List of towns in England, town and civil parish in the City of Southend-on-Sea, in the ceremonial county of Essex, England. In 2011, it had a population of 22,509.
Geography
Leigh- ...
which is managed by the
Essex Wildlife Trust
The Essex Wildlife Trust (EWT) is one of 46 wildlife trusts which cover the United Kingdom. The EWT was founded in 1959, and it describes itself as Essex's leading conservation charity, which aims to protect wildlife for the future and the people ...
. A narrow majority of the Site is the Southend on Sea Foreshore Local Nature Reserve.
The marshes and mudflats have internationally important numbers of wildfowl and wading birds, including the
dark-bellied brent goose
The brant or brent goose (''Branta bernicla'') is a small goose of the genus '' Branta''. There are three subspecies, all of which winter along temperate-zone sea-coasts and breed on the high-Arctic tundra.
The Brent oilfield was named after ...
,
grey plover
The grey plover or black-bellied plover (''Pluvialis squatarola'') is a large plover breeding in Arctic regions. It is a long-distance migrant, with a nearly worldwide coastal distribution when not breeding.
Taxonomy
The grey plover was forma ...
red knot
The red knot or just knot (''Calidris canutus'') is a medium-sized shorebird which breeds in tundra and the Arctic Cordillera in the far north of Canada, Europe, and Russia. It is a large member of the ''Calidris'' sandpipers, second only to the ...
. Scarce invertebrates, such as the
white-letter hairstreak
The white-letter hairstreak (''Satyrium w-album'') is a butterfly in the family Lycaenidae.
Appearance and behaviour
A dark little butterfly that spends the majority of its life in the tree tops, feeding on honeydew, making it best observed thr ...
and marbled white butterfly, have adapted to specific habitats in the marshes.