The site is a coastal marsh lying in a depression separated from the Atlantic by a row of dunes, but opening to the sea via a man-made channel equipped with a sluice gate. The wetland itself covers approximately 50 ha, but the IBA limits (which correspond to those of the SIBE) include some of the surrounding area and encompass 300 ha in total. Merja Halloufa is located only eight kilometres north-east of Merja Zerga (site MA010). It is fed by the Oued Souier, the underlying water-table, and by run-off from irrigated fields. The water-level is regulated artificially. The merja is surrounded by many villages and the neighbouring land is intensively cultivated for wheat, sugar-cane, strawberries under glass, and other horticultural produce. There are no trees and, apart from some fringing Juncus rushes, aquatic vegetation is sparse. The lake is shallow and its bed is practically flat, so that during summer the retreating water exposes large areas of ‘prairie’ which are used for grazing.
See Box for key species. Situated on the Atlantic coastal flyway, this site is important for its migratory winter visitors. It harbours an average of 1,000–4,000 ducks and up to 10,000 coots, as well as thousands of gulls (Larus fuscus and L. ridibundus). Merja Halloufa is also noteworthy for its wintering population of Netta rufina: the largest number ever observed in Morocco (300 birds) was recorded here.
Non-bird biodiversity: Pelobates varaldii, an endemic Moroccan amphibian, is present.
BirdLife International (2020) Important Bird Areas factsheet: Merja Halloufa. Downloaded from http://www.birdlife.org on 04/12/2020.