Ria de Aveiro (364)
Portugal, Europe
Site overview
KBA status: confirmed
Year of last assessment: 2002
National site name: Ria de Aveiro
Central coordinates: Latitude: 40.7000, Longitude: -8.6667
System: marine, terrestrial
Elevation (m): 0 to 79
Area of KBA (km2): 513.44102
Protected area coverage (%): 97.53
KBA classification: Regional
Legacy site: Yes
Site details
Site description: This site, located in the west and north-west of Portugal, includes a large estuarine area, salinas, freshwater marshes and alluvial forest associated with the River Vouga and its main tributaries, and shallower coastal waters offshore (to a depth of 20 m).
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: The site holds 20,000 or more wintering waterbirds on a regular basis, with important congregations of sea-duck offshore (Melanitta nigra) and waders on the intertidal flats (notably Calidris alpina). The freshwater marshes and estuarine areas support important breeding numbers of several waterbirds.
Habitats
Land use: agriculture | fisheries/aquaculture | forestry | hunting | military | nature conservation and research | tourism/recreation | urban/industrial/transport
| IUCN Habitat | Coverage % | Habitat detail |
|---|---|---|
| Marine Coastal/Supratidal | 22 | |
| Forest | 4 | |
| Marine Intertidal | 22 | |
| Grassland | 10 | |
| Marine Neritic | 29 | |
| Artificial - Terrestrial | 13 |
Threats
Summary of threats to biodiversity at KBA: The site is subject to several important impacts. The constant dredging of the channel that connects the whole area to the sea has increased tidal amplitude inside the lagoon system as well as water-flow. These two effects combine to increase erosion of sediments within the lagoon. The drainage and conversion to agriculture of inner parts of the lagoon are reducing the extent of alluvial forest and thus reducing the landscape diversity. Salinas are being destroyed by erosion or transformed into fish-farms. An invasive species of Acacia tree is strongly competing with native vegetation.
| Threat level 1 | Threat level 2 | Threat level 3 | Timing |
|---|---|---|---|
| Transportation & service corridors | Utility & service lines | Ongoing |
Additional information
References: Rosa et al.(2001c, in press)