Tejo estuary This is an IBA in Danger! 

Country/territory: Portugal

IBA criteria met: A1, A4i, A4iii, B1i, B2, C1, C2, C3, C4, C6 (2002)
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Area: 45,071 ha

Sociedade Portuguesa para o Estudo das Aves
IBA conservation status
Year of assessment (most recent) State (condition) Pressure (threat) Response (action)
2020 not assessed very high not assessed
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Site description (2002 baseline)
The largest wetland and estuary in Portugal, and one of the mainest in Europe, in extension and in natural value. Located in central Portugal, the site includes the upper and central parts of the River Tejo estuary and the valley of a small tributary (Ria Enguias). The site presents large expanses of mudflats and saltmarshes as result of soft slopes at its edges and its wideness of tide. At the edges of the IBA rice-fields are found and also an extensive area for agriculture and cattle-breed. Lisbon is located at the mouth of the River Tejo, and more than two million people live around this IBA.

Key biodiversity
The site holds 100,000 or more wintering waterbirds on a regular basis, and is the most important locality in Portugal for wintering flamingos, ducks, waders and gulls. The area also holds important numbers of a wide variety of breeding waterbirds. The reedbeds in the upper part of the estuary support large numbers of migrating passerines during autumn. The wintering population of Tetrax tetrax is significant at national level and represents near 1% of wintering european population. 46 of the near 200 species that occur here are included in Anex I of 79/409/CEE directive.

Recommended citation
BirdLife International (2023) Important Bird Area factsheet: Tejo estuary. Downloaded from on 22/09/2023.