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Location Portugal, Algarve
Central coordinates 7o 26.00' West  37o 12.00' North
IBA criteria A4i, B1i, B2, C2, C6
Area 2,147 ha
Altitude 0 - 42m
Year of IBA assessment 2002

Sociedade Portuguesa para o Estudo das Aves

Site description The Portuguese side of the Guadiana estuary, at the country's south-east corner. There is an extensive area of saltpans and of claimed land (used for cattle and sheep-grazing) that was formerly saltmarsh.

Key Biodiversity Important numbers of breeding, wintering and migrating waterbirds use this site, as do some steppic species such as Tetrax tetrax, Burhinus oedicnemus, Glareola prantincola and Melanocorypha calandra. This is the only portuguese site where Calandrella rufescens breeds. Untill 1999 Falco naumanni bred at this site.

Populations of IBA trigger species

Species Season Period Population estimate Quality of estimate IBA Criteria IUCN Category
Greater Flamingo Phoenicopterus roseus winter  2000  350-1,180 individuals  good  A4i, B1i, C2  Least Concern 
White Stork Ciconia ciconia resident  1996  100-150 individuals  medium  B2, C6  Least Concern 
Eurasian Spoonbill Platalea leucorodia winter  1996  200-500 individuals  medium  A4i, B1i, C2  Least Concern 
Little Bustard Tetrax tetrax breeding  2002  10-20 individuals  good  C6  Near Threatened 
Little Bustard Tetrax tetrax winter  2002  90-100 individuals  good  C6  Near Threatened 
Burhinus oedicnemus breeding  2002  common  C6  Not Recognised 
Burhinus oedicnemus winter  2002  200-300 individuals  good  C6  Not Recognised 
Himantopus himantopus resident  2001  200 breeding pairs  good  A4i, B1i, C2, C6  Not Recognised 
Pied Avocet Recurvirostra avosetta winter  1996  400-560 individuals  good  B2, C6  Least Concern 
Pied Avocet Recurvirostra avosetta breeding  2001  121-198 breeding pairs  good  B2, C6  Least Concern 
Collared Pratincole Glareola pratincola breeding  2000  rare  C6  Least Concern 
Little Tern Sternula albifrons breeding  2001  50-90 breeding pairs  good  B2, C6  Least Concern 
Calandra Lark Melanocorypha calandra breeding  1996  rare  C6  Least Concern 
Thekla Lark Galerida theklae resident  2001  frequent  C6  Least Concern 

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%) no or imperceptible deterioration low

Protected areas

Protected area Designation Area (ha) Relationship with IBA Overlap with IBA (ha)  
Sapais de Castro Marim Wetlands of International Importance (Ramsar) 2,235 protected area overlaps with site 2,235  
Sapal de Castro Marim e Vila Real de Santo António Nature Reserve 2,308 protected area overlaps with site 1,876  


IUCN habitat Habitat detail Extent (% of site)
Wetlands (inland) Standing brackish and salt water  -
Artificial - terrestrial Arable land; Forestry plantations; Perennial crops, orchards and groves  -
Coastline Mud flats & sand flats; Salt marshes; Tidal rivers & enclosed tidal waters  -

Land use

Land-use Extent (% of site)
water management -
fisheries/aquaculture -
nature conservation and research -
tourism/recreation -
agriculture -

Protection status National Nature Reserve Sapal de Castro Marim e de Vila Real de Santo António; Special Protection Area Sapal de Castro Marim; SCI proposal Ria Formosa/Castro MarimInternational Special Protection Area Sapal de Castro Marim; Ramsar Wetland Site (7PT010)

References Farinha & Trinidade (1994), Mendes (1995), Costa & Rufino (1997), Leitão & Farinha (1998), Dias (1999), Costa et al. (2000), Leitão (2002a, 2002b).

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Recommended citation  BirdLife International (2016) Important Bird and Biodiversity Area factsheet: Castro Marim. Downloaded from on 25/10/2016

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