Rio Mansôa and Gêba estuary (6384)
Guinea-Bissau, Africa
Site overview
KBA status: confirmed
Global KBA criteria: D1a
Year of last assessment: 2001
National site name: Rio Mansôa and Gêba estuary
Central coordinates: Latitude: 11.9318, Longitude: -15.7715
System: marine, terrestrial
Elevation (m): 0 to 10
Area of KBA (km2): 1197.42939
KBA classification: Global
Legacy site: Yes
Site details
Site description: The site comprises much of the estuary, fringing mangrove and woodland of the Rio Mansôa, together with an area of the northern shore of the Canal do Gêba, the estuary of the larger Rio Gêba, immediately to the east. The site includes two large, predominantly mangrove-covered islands—Ilha de Jeta and Ilha de Pexice—as well as several smaller ones in the mouth of the Rio Mansôa. Eastwards the site extends along the shoreline of the Canal do Gêba as far as the Ilhéu dos Pássaros, an islet near the northern shore of the estuary of the Rio Gêba, a little way downstream of the city of Bissau. The banks of the mouth of the Rio Gêba are bordered with mangroves and soft mud, while there are sandbars and mudbanks in the channel. The site includes 175,000 ha of mudflats, 3,000 ha of mangrove and 13,000 ha of marsh.
Rationale for qualifying as KBA: This site qualifies as a Key Biodiversity Area of international significance that meets the thresholds for at least one criterion described in the Global Standard for the Identification of KBAs.
Additional biodiversity: See Box and Table 2 for key species. The Ilhéu dos Pássaros is an important roost-site where over 15,000 birds have been recorded. Counts only exist for the eastern parts of the site, the Rio Gêba area, which alone held over 37,000 wintering waders. A count of 1,500 Phoenicopterus minor were recorded in March 1990. Non-bird biodiversity: The mammal Trichechus senegalensis (VU) occurs.
Delineation rationale: 2012-12-17 (BL Secretariat): the original site boundary has been clipped to the coastline (marine areas removed) to avoid overlap with the new marine IBA identified adjacent to this site in October 2012; site area has been correspondingly reduced from 191000 ha to 119743 ha.
Habitats
Land use: nature conservation and research
| IUCN Habitat | Coverage % | Habitat detail |
|---|---|---|
| Savanna | 5 | |
| Forest | 75 | |
| Artificial - Terrestrial | 16 | |
| Shrubland | 1 |
Threats
Summary of threats to biodiversity at KBA: Part of the site has been classified as the Rio Mansôa Non-hunting Reserve. A considerable area of what was originally mangrove has been cleared around the city of Bissau. This practice is continuing which, with increasing population pressure, is likely to have serious consequences for coastal fisheries. Any industrial development in Guinea-Bissau is likely to be centred on Bissau and thus there is a potential threat of pollution to at least parts of this site.
Additional information
References: Altenburg and van Spanje (1989), Ledant (1985), Zwarts (1988).