Tagus Estuary Natural Reserve ( pt, Reserva Natural do Estuário do Tejo) is a

natural reserve A nature reserve (also known as a wildlife refuge, wildlife sanctuary, biosphere reserve or bioreserve, natural or nature preserve, or nature conservation area) is a protected area of importance for flora, fauna, or features of geological or o ...

Portugal Portugal, officially the Portuguese Republic ( pt, República Portuguesa, links=yes ), is a country whose mainland is located on the Iberian Peninsula of Southwestern Europe, and whose territory also includes the Atlantic archipelagos of ...

. It is one of the 30 areas which are officially under protection in the country. The

estuary An estuary is a partially enclosed coastal body of brackish water with one or more rivers or streams flowing into it, and with a free connection to the open sea. Estuaries form a transition zone between river environments and maritime environm ...

of the

Tagus River The Tagus ( ; es, Tajo ; pt, Tejo ; see below) is the longest river in the Iberian Peninsula. The river rises in the Montes Universales near Teruel, in mid-eastern Spain, flows , generally west with two main south-westward sections, to ...

is the largest wetland in the country and one of the most important in Europe, a sanctuary for fish, molluscs, crustaceans, and especially to birds that stop-over on their migration between northern Europe and Africa. It is the largest estuary in western Europe, with about , and regularly hosts 50,000 wintering waterfowl.

Characterization

The Nature Reserve was established in 1976, covering an area of , characterized by an extensive surface of estuarine waters, vast fields intersected by creeks, marshes, salt flats and alluvial agricultural land (marshlands). Not exceeding above sea level and a depth of , distributed over the counties of Alcochete, Benavente and Vila Franca de Xira, the reserve falls mostly in the upstream area of the estuary of the Tagus which, with an area extending over about , is the largest in Western Europe. Around the estuary a

saltmarsh A salt marsh or saltmarsh, also known as a coastal salt marsh or a tidal marsh, is a coastal ecosystem in the upper coastal intertidal zone between land and open saltwater or brackish water that is regularly flooded by the tides. It is dominated ...

has developed which is a zone of high productivity of

polychaetes Polychaeta () is a paraphyletic class of generally marine annelid worms, commonly called bristle worms or polychaetes (). Each body segment has a pair of fleshy protrusions called parapodia that bear many bristles, called chaetae, which are made ...

, molluscs and

crustacean Crustaceans (Crustacea, ) form a large, diverse arthropod taxon which includes such animals as decapods, seed shrimp, branchiopods, fish lice, krill, remipedes, isopods, barnacles, copepods, amphipods and mantis shrimp. The crustacean group can ...

s, is an important breeding area for various fish species. However, it is the water birds which give the Tagus estuary its international importance. The flocks of wintering species reach up to about 120,000 individuals. The counts regularly carried out in this protected area during the winter show more than 10,000 ducks and 50,000 shorebirds. In the case of the

pied avocet The pied avocet (''Recurvirostra avosetta'') is a large black and white wader in the avocet and stilt family, Recurvirostridae. They breed in temperate Europe and across the Palearctic to Central Asia then on to the Russian Far East. It is a ...

(''Recurvirostra avosetta''), up to 25% of the population wintering in Europe has been counted on the Tagus Estuary. The many other species present attest to the biological richness and value for nature conservation in this region: the

greater flamingo The greater flamingo (''Phoenicopterus roseus'') is the most widespread and largest species of the flamingo family. It is found in Africa, the Indian subcontinent, the Middle East, and in southern Europe. Taxonomy The greater flamingo was desc ...

(''Phoenicopterus roseus''),

greylag goose The greylag goose or graylag goose (''Anser anser'') is a species of large goose in the waterfowl family Anatidae and the type species of the genus ''Anser''. It has mottled and barred grey and white plumage and an orange beak and pink legs. A ...

(''Anser anser''), the

dunlin The dunlin (''Calidris alpina'') is a small wader, formerly sometimes separated with the other "stints" in the genus ''Erolia''. The English name is a dialect form of "dunling", first recorded in 1531–1532. It derives from ''dun'', "dull brown ...

(''Calidris alpina''), black-tailed godwit (''Limosa limosa''),

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 ...

(''Circus cyaneus''),

osprey The osprey (''Pandion haliaetus''), , also called sea hawk, river hawk, and fish hawk, is a diurnal, fish-eating bird of prey with a cosmopolitan range. It is a large raptor reaching more than in length and across the wings. It is brown o ...

(''Pandion haliaetus''),

bluethroat The bluethroat (''Luscinia svecica'') is a small passerine bird that was formerly classed as a member of the thrush family Turdidae, but is now more generally considered to be an Old World flycatcher, Muscicapidae. It, and similar small Europea ...

(''Luscina svecica''),

common firecrest The common firecrest (''Regulus ignicapilla''), also known as the firecrest, is a very small passerine bird in the kinglet family. It breeds in most of temperate Europe and northwestern Africa, and is partially migratory, with birds from central ...

(''Regulus ignicapillus'') and

Eurasian penduline tit The Eurasian penduline tit or European penduline tit (''Remiz pendulinus'') is a passerine bird of the genus ''Remiz''. It is relatively widespread throughout the western Palearctic. It is migratory in the northern part of its range but resident ...

(''Remiz pendulinus''). Reserva Natural do Estuário do Tejo (11160723166)

In the wetlands around the estuary nesting birds include

red-crested pochard The red-crested pochard (''Netta rufina'') is a large diving duck. The scientific name is derived from Greek language, Greek ''Netta'' "duck", and Latin ''rufina'', "golden-red" (from ''rufus'', "ruddy"). Its breeding habitat is lowland marshes a ...

(''Netta rufina''),

little bittern The little bittern or common little bittern (''Ixobrychus minutus'') is a wading bird in the heron family, Ardeidae. ''Ixobrychus'' is from Ancient Greek ''ixias'', a reed-like plant and ''brukhomai'', to bellow, and ''minutus'' is Latin for "sm ...

(''Ixobrychus minutus''), little egret (''Egretta garzetta'') and purple heron (''Ardea purpurea''),

marsh harrier The marsh harriers are birds of prey of the harrier subfamily. They are medium-sized raptors and the largest and broadest-winged harriers. Most of them are associated with marshland and dense reedbeds. They are found almost worldwide, excluding ...

(''Circus aeruginosus''],

Montagu's harrier Montagu's harrier (''Circus pygargus'') is a migratory bird of prey of the harrier family. Its common name commemorates the British naturalist George Montagu. Taxonomy The first formal description of Montagu's harrier was by the Swedish na ...

(''Circus pyagurgus''),

black-winged stilt The black-winged stilt (''Himantopus himantopus'') is a widely distributed very long-legged wader in the avocet and stilt family ( Recurvirostridae). The scientific name ''H. himantopus'' is sometimes applied to a single, almost cosmopolitan sp ...

(''Himantopus himantopus''),

collared pratincole The collared pratincole (''Glareola pratincola''), also known as the common pratincole or red-winged pratincole, is a wader in the pratincole family, Glareolidae. As with other pratincoles, it is native to the Old World. Taxonomy The collared p ...

(''Glareola pratincola'') and

little tern The little tern (''Sternula albifrons'') is a seabird of the family Laridae. It was formerly placed into the genus ''Sterna'', which now is restricted to the large white terns. The genus name is a diminutive of '' Sterna'', "tern". The specific ' ...

(''Sternula albifrons''). While the associated redbeds contain

great reed warbler The great reed warbler (''Acrocephalus arundinaceus'') is a Eurasian passerine in the genus '' Acrocephalus''. The genus name ''Acrocephalus'' is from Ancient Greek ''akros'', "highest", and ''kephale'', "head". It is possible that Naumann and ...

(''Acrocephalus arundinaceus''),

Savi's warbler Savi's warbler (''Locustella luscinioides'') is a species of Old World warbler in the grass warbler genus ''Locustella''. It breeds in Europe and the western Palearctic. It is migratory, wintering in northern and sub-Saharan Africa. This small ...

(''Locustella luscinioides'') and other warblers. The nearby fields have stone-curlew (''Burhinus oedicnemus'') and

calandra lark The calandra lark (''Melanocorypha calandra'') or European calandra-lark breeds in warm temperate countries around the Mediterranean and eastwards through Turkey into northern Iran and southern Russia. It is replaced further east by its relative ...

(''Melanocorypha calandra'') breed on adjacent farmland.

Little bustard The little bustard (''Tetrax tetrax'') is a bird in the bustard family, the only member of the genus ''Tetrax''. The genus name is from Ancient Greek and refers to a gamebird mentioned by Aristophanes and others. Distribution It breeds in South ...

(''Tetrax tetrax'') occurs all year but is more numerous in winter. Raptors which may be seen over the fields include

black-winged kite The black-winged kite (''Elanus caeruleus''), also known as the black-shouldered kite (not to be confused with the closely-related Australian species of the same name), is a small diurnal bird of prey in the family Accipitridae best known for it ...

(''Elanus caeruleus''),

short-toed eagle The short-toed snake eagle (''Circaetus gallicus''), also known as the short-toed eagle, is a medium-sized bird of prey in the family Accipitridae, which also includes many other diurnal raptors such as kites, buzzards and harriers. The genus na ...

(''Circaetus gallicus'') and booted eagle (''Aquila pennatus''). Nearby patches of woodland hold

short-toed treecreeper The short-toed treecreeper (''Certhia brachydactyla'') is a small passerine bird found in woodlands through much of the warmer regions of Europe and into north Africa. It has a generally more southerly distribution than the other European treecr ...

(''Certhia brachydactyla''),

European nightjar The European nightjar (''Caprimulgus europaeus''), common goatsucker, Eurasian nightjar or just nightjar, is a crepuscular and nocturnal bird in the nightjar family that breeds across most of Europe and the Palearctic to Mongolia and Northwest ...

(''Caprimulgus europaeus''), red-necked nightjar (''Caprimulgus ruficollis''),

Iberian magpie The Iberian magpie (''Cyanopica cooki'') is a bird in the crow family. It is long and similar in overall shape to the Eurasian magpie (''Pica pica'') but is more slender with proportionately smaller legs and bill. It belongs to the genus '' Cy ...

(''Cyanopica cooki'') and many passerines. During the Spring and Autumn many species stopover on the Tagus during their migration these include

curlew sandpiper The curlew sandpiper (''Calidris ferruginea'') is a small wader that breeds on the tundra of Arctic Siberia. It is strongly migratory, wintering mainly in Africa, but also in south and southeast Asia and in Australia and New Zealand. It is a v ...

(''Calidris ferruginea'') in large numbers with many other shorebirds in smaller numbers,

common redshank The common redshank or simply redshank (''Tringa totanus'') is a Eurasian wader in the large family Scolopacidae. Taxonomy The common redshank was formally described by the Swedish naturalist Carl Linnaeus in 1758 in the tenth edition of his ...

(''Tringa totanus'') and black-tailed godwits reach their peak numbers during migration too. Other migrants which may be seen include

Eurasian spoonbill The Eurasian spoonbill (''Platalea leucorodia''), or common spoonbill, is a wading bird of the ibis and spoonbill family Threskiornithidae. The genus name ''Platalea'' is from Latin and means "broad", referring to the distinctive shape of the ...

(''Platalea alba''),

Mediterranean gull The Mediterranean gull (''Ichthyaetus melanocephalus'') is a small gull. The scientific name is from Ancient Greek. The genus ''Ichthyaetus'' is from ''ikhthus'', "fish", and ''aetos'', "eagle", and the specific ''melanocephalus'' is from ''mel ...

(''Larus melanocephalus'') and

black tern The black tern (''Chlidonias niger'') is a small tern generally found in or near inland water in Europe, Western Asia and North America. As its name suggests, it has predominantly dark plumage. In some lights it can appear blue in the breeding se ...

(''Chlidonias niger'') and many passerines.

Conservation status

* 1976 - Is created the Natural Reserve of the Tagus Estuary, through Decree-Law No. 565/76. * 1980 - Moves to make the Wetlands of International Importance by the Ramsar Convention. * 1994 - Is hereby established a Special Protection Area for Wild Birds, under Directive 79/409/EEC.

References

{{Protected areas of Portugal Nature reserves in Portugal Ramsar sites in Portugal Geography of Lisbon District Natura 2000 in Portugal Tagus