Sado estuary (371)
Portugal, Europe
Site overview
KBA status: confirmed
Year of last assessment: 2002
National site name: Estuário do Sado
Central coordinates: Latitude: 38.4500, Longitude: -8.7167
System: marine, terrestrial
Elevation (m): 0 to 30
Area of KBA (km2): 246.29354
Protected area coverage (%): 99.48
KBA classification: Regional
Legacy site: Yes
Site details
Site description: A large estuary with extensive mudflats and saltmarshes, located in central Portugal, c.50 km south of Lisbon. Setúbal is the main town in its vicinity. The inner part of the estuary is bordered by rice-fields and reedbeds, whereas the north-western limits are densely populated and the south-western parts are sheltered from the open sea by a sandbar.
Rationale for qualifying as KBA: This site qualifies as a Key Biodiversity Area of international significance that was identified using previously established criteria and thresholds for the identification of Important Bird and Biodiversity Areas (IBAs) and for which available data indicate that it does not meet global KBA criteria and thresholds set out in the Global Standard.
Additional biodiversity: Several waterbird species (mainly waders) occur in winter in large, internationally significant numbers, and the site holds 20,000 or more wintering waterbirds on a regular basis. There are also important numbers of breeding waterbirds, notably Himantopus himantopus and Sterna albifrons. The rice-fields are an important feeding ground for the egrets and herons from the nearby breeding colony at Murta dam (024). More than 500,000 Columba palumbus roost within the IBA in winter.
Habitats
Land use: agriculture | fisheries/aquaculture | forestry | hunting | nature conservation and research | tourism/recreation | urban/industrial/transport
| IUCN Habitat | Coverage % | Habitat detail |
|---|---|---|
| Marine Coastal/Supratidal | 17 | |
| Marine Intertidal | 17 | |
| Forest | 17 | |
| Artificial - Terrestrial | 17 | |
| Shrubland | 17 | |
| Marine Neritic | 17 |
Threats
Summary of threats to biodiversity at KBA: Over 30% of the available area of saltpans has been transformed into fish-farms in the course of the last ten years. There are plans for large-scale dredging at the mouth of the estuary that may affect water-flow and sediment deposition inside the estuary, thus indirectly affecting the bird community.