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Location Portugal, Centro
Central coordinates 8o 40.00' West  40o 42.00' North
IBA criteria A4i, A4iii, B1i, B2, B3, C2, C3, C4, C6
Area 51,378 ha
Altitude 0 - 79m
Year of IBA assessment 2002

Sociedade Portuguesa para o Estudo das Aves

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).

Key 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.

Populations of IBA trigger species

Species Season Period Population estimate Quality of estimate IBA Criteria IUCN Category
Ixobrychus minutus breeding  frequent  C6  Not Recognised 
Purple Heron Ardea purpurea breeding  2002  150-200 breeding pairs  good  B2, C6  Least Concern 
Western Marsh-harrier Circus aeruginosus resident  1999  13 breeding pairs  good  C6  Least Concern 
Himantopus himantopus breeding  1996  50-100 breeding pairs  good  C6  Not Recognised 
Pied Avocet Recurvirostra avosetta winter  2002  800-1,800 individuals  good  A4i, B1i, B2, C2, C6  Least Concern 
Charadrius alexandrinus breeding  1995  common  B3  Not Recognised 
Charadrius alexandrinus winter  2002  660-6,000 individuals  good  A4i, B1i, C3  Not Recognised 
Common Ringed Plover Charadrius hiaticula winter  2002  800-1,800 individuals  good  A4i, B1i  Least Concern 
Dunlin Calidris alpina winter  2002  7,800-10,700 individuals  good  B3, C3  Least Concern 
Little Tern Sternula albifrons breeding  1996  10-15 breeding pairs  good  C6  Least Concern 
A4iii Species group - waterbirds winter  2002  20,000 individuals  unknown  A4iii, C4   

IBA Monitoring

2005 low not assessed not assessed
Good - based on reliable and complete / representative data

Transportation and service corridors utility & service lines happening now small area/few individuals (<10%) very rapid to severe deterioration low

Protected areas

Protected area Designation Area (ha) Relationship with IBA Overlap with IBA (ha)  
Dunas de S. Jacinto Nature Reserve 996 protected area contained by site 681  


IUCN habitat Habitat detail Extent (% of site)
Forest Alluvial and very wet forest; Native coniferous woodland  4%
Grassland Humid grasslands  10%
Wetlands (inland) Water fringe vegetation  -
Sea Open Sea  29%
Artificial - terrestrial Arable land  13%
Coastline Lagoons; Mud flats & sand flats; Salt marshes; Sand dunes & beaches; Tidal rivers & enclosed tidal waters  -

Land use

Land-use Extent (% of site)
agriculture -
fisheries/aquaculture -
forestry -
hunting -
military -
nature conservation and research -
tourism/recreation -
urban/industrial/transport -

Protection status National 681 ha of IBA covered by Nature Reserve (Dunas de S. Jacinto, 681 ha). 51378 ha of IBA covered by Special Protection Area (Ria de Aveiro, 52,720 ha).International Special Protection Area Ria de Aveiro,

References Rosa et al.(2001c, in press)

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Recommended citation  BirdLife International (2016) Important Bird and Biodiversity Area factsheet: Ria de Aveiro. Downloaded from on 27/10/2016

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