The site consists of the shallow dayet, or lake, of Sidi Bou Ghaba. Six kilometres long, but only 400 m broad at its widest point, the lake is enclosed between two rows of fossil dunes inland from, but parallel to, the Atlantic coast, some 30 km north of Rabat. The dunes are covered by Juniperus phoenicea woodland, intermixed with other woody species such as Pistacia lentiscus, Olea europea and Retama monosperma. The lake is fresh water, fed by rainfall and run-off. There are extensive areas with well-developed reedbeds and marshy vegetation consisting of Phragmites communis, Juncus acutus, J. maritimus, Cyperus laevigatus, Scirpus lacustris, S. holoschoenus, and Typha angustifolia. The lake is fringed with Tamarix gallica, Populus alba and introduced Eucalyptus species. The site is accessible by a tarmac road and receives large numbers of local visitors each year (see Conservation issues).
See Box and Table 2 for key species. An important site on the Atlantic coastal flyway, the Réserve Biologique receives thousands of wintering and passage migrants every year, particularly waterfowl. Around 107 species are regularly recorded, of which 35 breed. Sidi Bou Ghaba is best known for its wintering population of Marmaronetta angustirostris, which can number several hundred. Around 10 pairs breed each year. Aythya nyroca is a passage migrant in small numbers (maximum four individuals). Of the seven species of the Mediterranean North Africa biome that occur, five breed, while two (Falco eleonorae and Caprimulgus ruficollis) are non-breeding visitors.
Pressure/threats to key biodiversity
The site is completely protected. The 652 ha Canton Forestier de Sidi Bou Ghaba was created in 1916. In 1951 the Canton and an additional 150 ha to its south were gazetted as a ‘Site classé’ by the Ministère des Affaires Culturelles (Direction des Monuments Historiques et Sites). A portion of the Canton Forestier, coincidentally also 150 ha, encompassing the southern end of the lagoon itself, was classed as a Réserve Biologique in 1974 by AEFCS. The site is a priority 1 SIBE (No. L18), and one of the country’s four designated Ramsar Sites. The land belongs to the state, and is currently administered by the AEFCS. The IBA limits correspond to the Canton Forestier, and therefore include both protected areas. Existing legislation bans hunting, fishing, water-sports, collection of firewood, etc. and confers adequate protection. However, enforcement is difficult, and sometimes the sheer weight of visitor numbers can be problematic, since the lake is an extremely popular weekend picnic site. An environmental education centre, the Centre National d’Education Environnementale, with an accompanying nature trail was built in the Réserve in the 1990s by BirdLife International with funding from British Birdwatching Fair, Vogelbescherming Nederland and SPANA-UK, and support for equipping and running costs from the EU, SPANA-Morocco and AEFCS. By the beginning of 1997 it had received 30,000 visitors, including many parties of schoolchildren.Management of the lake must ensure that accumulation of organic sediments does not gradually result in infilling and a reduction in the surface area of open water. The main potential threats are pollution from agricultural run-off and lowering of the groundwater table due to irrigation of surrounding cultivated land. A coherent management plan for the whole area is urgently required.