The area is situated on the western side of Boavista, at the mouth of the Ribeira do Rabil, or Ribeira Grande, the main watercourse on the island. The site comprises an area extending c.7 km east from the coast to the road connecting Vila de Sal Rei (the island’s main town) with the airfield and the village of Rabil. Surrounded by mobile sand-dunes and Tamarix senegalensis bushes, with a wide lagoon at the stream’s outlet, the ribeira is scenically attractive. Following rain, the ribeira may swell to an impressive stream but, for most of the year, it consists of brackish pools which gradually dry out as the dry season advances. The lagoon, however, is filled with water all year. Besides tamarix, the vegetation is dominated by Cyperus spp., Zygophyllum spp. and Euphorbia spp.
See Box and Table 2 for key species. The lagoon and adjacent ribeira usually hold good numbers of wintering migrant waders—16 species have been recorded. Numbers of waders usually do not exceed c.300 birds, but this is unusual in the islands. The only breeding wader is Charadrius alexandrinus. In addition, migrant herons (four species), Platalea leucorodia, and terns (four species) are regularly recorded in the area. Formerly, Marmaronetta angustirostris and Gallinula chloropus bred along the lagoon, but neither has been recorded in recent years. The bushes along the lagoon also provide a popular roost for Bubulcus ibis. A representative arid-zone avifauna occurs in the surrounding dunes and bushes and includes Coturnix coturnix, Cursorius cursor, Ammomanes cincturus, Alaemon alaudipes, Sylvia conspicillata, Passer hispaniolensis and P. iagoensis.
Non-bird biodiversity: The endemic lizards Mabuya stangeri and Hemidactylus bouvieri occur.
BirdLife International (2019) Important Bird Areas factsheet: Ribeira do Rabil. Downloaded from http://www.birdlife.org on 24/05/2019.