South Thames Estuary and Marshes is a biological

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 ...

which stretches between

Gravesend Gravesend is a town in northwest Kent, England, situated 21 miles (35 km) east-southeast of Charing Cross (central London) on the Bank (geography), south bank of the River Thames and opposite Tilbury in Essex. Located in the diocese of Ro ...

and the mouth of the

River Medway The River Medway is a river in South East England. It rises in the High Weald AONB, High Weald, East Sussex and flows through Tonbridge, Maidstone and the Medway conurbation in Kent, before emptying into the Thames Estuary near Sheerness, a to ...

Kent Kent is a county in South East England and one of the home counties. It borders Greater London to the north-west, Surrey to the west and East Sussex to the south-west, and Essex to the north across the estuary of the River Thames; it faces ...

. Part of it is a

Nature Conservation Review ''A Nature Conservation Review'' is a two-volume work by Derek Ratcliffe, published by Cambridge University Press in 1977. It set out to identify the most important places for nature conservation in Great Britain. It is often known by the initial ...

site, Grade I, and part is a

Royal Society for the Protection of Birds The Royal Society for the Protection of Birds (RSPB) is a charitable organisation registered in England and Wales and in Scotland. It was founded in 1889. It works to promote conservation and protection of birds and the wider environment throug ...

nature reserve. It is part of the Thames Estuary and Marshes

Ramsar Ramsar may refer to: * Places so named: ** Ramsar, Mazandaran, city in Iran ** Ramsar, Rajasthan, village in India * Eponyms of the Iranian city: ** Ramsar Convention concerning wetlands, signed in Ramsar, Iran ** Ramsar site, wetland listed in ...

internationally important wetland site and

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 ...

under the

European Union The European Union (EU) is a supranational political and economic union of member states that are located primarily in Europe. The union has a total area of and an estimated total population of about 447million. The EU has often been des ...

Directive on the Conservation of Wild Birds. The site consists of a range of habitats including mudflats, saltmarsh, grazing marsh and stretches of shingle. Inland are freshwater lagoons and some patches of deciduous woodland. Over 20,000 migratory waterfowl use this site in the winter, and some species such as

greater white-fronted goose The greater white-fronted goose (''Anser albifrons'') is a species of goose related to the smaller lesser white-fronted goose (''A. erythropus''). It is named for the patch of white feathers bordering the base of its bill, in fact ''albifrons ...

shelduck The shelducks, most species of which are found in the genus ''Tadorna'' (except for the Radjah shelduck, which is now found in its own monotypic genus ''Radjah''), are a group of large birds in the Tadorninae subfamily of the Anatidae, the biologi ...

gadwall The gadwall (''Mareca strepera'') is a common and widespread dabbling duck in the family Anatidae. Taxonomy The gadwall was first described by Carl Linnaeus in his landmark 1758 10th edition of ''Systema Naturae''. DNA studies have shown that ...

teal alt=American teal duck (male), Green-winged teal (male) Teal is a greenish-blue colour. Its name comes from that of a bird — the Eurasian teal (''Anas crecca'') — which presents a similarly coloured stripe on its head. The word is ofte ...

northern pintail The pintail or northern pintail (''Anas acuta'') is a duck species with wide geographic distribution that breeds in the northern areas of Europe and across the Palearctic and North America. It is migratory and winters south of its breeding ra ...

shoveler The shovelers or shovellers are four species of dabbling ducks with long, broad spatula-shaped beaks: * Red shoveler, ''Anas platalea'' * Cape shoveler, ''Anas smithii'' * Australasian shoveler, ''Anas rhynchotis'' * Northern shoveler, ''Anas cl ...

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 ...

curlew The curlews () are a group of nine species of birds in the genus ''Numenius'', characterised by their long, slender, downcurved bills and mottled brown plumage. The English name is imitative of the Eurasian curlew's call, but may have been in ...

and

black-tailed godwit The black-tailed godwit (''Limosa limosa'') is a large, long-legged, long-billed shorebird first described by Carl Linnaeus in 1758. It is a member of the godwit genus, ''Limosa''. There are four subspecies, all with orange head, neck and chest ...

are present in internationally important numbers. There are also a number of breeding birds including

garganey The garganey (''Spatula querquedula'') is a small dabbling duck. It breeds in much of Europe and across the Palearctic, but is strictly migratory, with the entire population moving to southern Africa, India (in particular Santragachi), Banglades ...

avocet The four species of avocets are a genus, ''Recurvirostra'', of waders in the same avian family as the stilts. The genus name comes from Latin , 'curved backwards' and , 'bill'. The common name is thought to derive from the Italian ( Ferrarese) w ...

, northern pintail,

bearded reedling The bearded reedling (''Panurus biarmicus'') is a small, sexual dimorphism, sexually dimorphic reed bed, reed-bed passerine bird. It is frequently known as the bearded tit, due to some similarities to the long-tailed tit, or the bearded parrotbil ...

hen harrier The hen harrier (''Circus cyaneus'') is a bird of prey. It breeds in Eurasia. The term "hen harrier" refers to its former habit of preying on free-ranging fowl. It migrates to more southerly areas in winter. Eurasian birds move to southern Eur ...

short-eared owl The short-eared owl (''Asio flammeus'') is a widespread grassland species in the family Strigidae. Owls belonging to genus ''Asio'' are known as the eared owls, as they have tufts of feathers resembling mammalian ears. These "ear" tufts may or ...

ruff Ruff may refer to: Places *Ruff, Virginia, United States, an unincorporated community *Ruff, Washington, United States, an unincorporated community Other uses *Ruff (bird) (''Calidris pugnax'' or ''Philomachus pugnax''), a bird in the wader fami ...

common tern The common tern (''Sterna hirundo'') is a seabird in the family Laridae. This bird has a circumpolar distribution, its four subspecies breeding in temperate and subarctic regions of Europe, Asia and North America. It is strongly migratory ...

and

European golden plover The European golden plover (''Pluvialis apricaria''), also known as the European golden-plover, Eurasian golden plover, or just the golden plover within Europe, is a largish plover. This species is similar to two other golden plovers: the America ...

. There are nationally scarce plants on dykes and the drier parts of the site, and the saltmarsh is dominated by salt grasses, the glassworts ''

Salicornia ''Salicornia'' is a genus of succulent, halophytic (salt tolerant) flowering plants in the family Amaranthaceae that grow in salt marshes, on beaches, and among mangroves. ''Salicornia'' species are native to North America, Europe, Central Asia, ...

'',

sea aster ''Tripolium pannonicum'', called sea aster or seashore aster and often known by the synonyms ''Aster tripolium'' or ''Aster pannonicus'', is a flowering plant, native to Eurasia and northern Africa, that is confined in its distribution to salt ma ...

sea lavender ''Limonium'' is a genus of 120 flowering plant species. Members are also known as sea-lavender, statice, caspia or marsh-rosemary. Despite their common names, species are not related to the lavenders or to rosemary. They are instead in Plumbag ...

and sea purslane. Also present are the nationally scarce plants

golden samphire The golden samphire (''Limbarda crithmoides'') is a perennial coastal species, which may be found growing on salt marsh or sea cliffs across western and southern Europe and the Mediterranean. Golden samphire has a tufted habit, and the plant may ...

and '' Puccinellia fasciculata''. The diverse invertebrates include nationally rare beetles, flies and

true bug Hemiptera (; ) is an order of insects, commonly called true bugs, comprising over 80,000 species within groups such as the cicadas, aphids, planthoppers, leafhoppers, assassin bugs, bed bugs, and shield bugs. They range in size from to around ...

s; the scarce emerald damselfly and eight species of water beetle, including the great silver water beetle, are found here.

References

{{SSSIs Kent Sites of Special Scientific Interest in Kent Nature Conservation Review sites Ramsar sites in England Thames Estuary