El Houareb reservoir is a man-made water-body built about 20 years ago on the Oued Merguellil, 35 km east of Kairouan, for flood-control and water-supply purposes. Where the river emerges from the Dorsale the reservoir is bordered by higher land, but also has extensive flat shores. It retains the waters which once flowed into Sebkha Kelbia (site TN020). It has an average depth of nearly 20 m, but in periods of poor rainfall, it can remain completely dry for several years on end. The surrounding vegetation is composed mainly of Tamarix africana, Typha angustifolia and Juncus species. The waterplant Potamogeton pectinatus grows commonly in the reservoir and provides the main food-source for wildfowl.
See Box for key species. The reservoir has become one of the most important sites in Tunisia for breeding M. angustirostris and O. leucocephala (whose numbers appear to be augmented in winter)—although it is not clear where these species go in dry years. Other species, including Podiceps cristatus and Tachybaptus ruficollis, also breed. The site is a wintering site for a broad array of species, including Phalacrocorax carbo, Casmerodius albus, Anas penelope, A. acuta, A. clypeata, Aythya ferina, A. fuligula and Fulica atra. In addition, eight species of the Mediterranean North Africa biome (A01) have been recorded (see Table 2).
Non-bird biodiversity: None known to BirdLife International.
Pressure/threats to key biodiversity
Uncontrolled hunting is the main threat to waterbirds. There are no obvious threats to the habitat and the site is patrolled by waterworks staff.
BirdLife International (2021) Important Bird Areas factsheet: Barrage El Houareb. Downloaded from
http://www.birdlife.org on 20/04/2021.