Like Sidi Khelifa (site TN016), situated some 30 km north along the coast, Sebkhet Halk el Menzel is partly coastal lagoon, partly saline depression, but is also linked to the inland sites of Kelbia (site TN020) and Oued Sed (TN018). In very wet years, Kelbia flows out to the sea, via Oued Sed, and reaches the sea through Halk el Menzel. It is likely that the freshwater springs round Oued Sed contribute to provision of water for Halk el Menzel in the summer, and there may be some reverse flood of seawater through the dune cordon, since Halk el Menzel retains some water in most summers. The surrounding vegetation is halophytic and includes Arthrocnemum, Salicornia and Atriplex species.
See Box for key species. The site’s location, on the coast along a major north–south flyway, with water available for most of the year, means that, in addition to overwintering species (such as Platalea leucorodia, a variety of ducks including Tadorna tadorna, Anas acuta and A. clypeata, and waders), the site attracts many passing migrants, including waders such as Limosa limosa, Numenius arquata, N. phaeopus and terns. In winters, when other roosting sites are dry, Grus grus may use the site as a roost. Breeding birds include Sterna albifrons and, possibly, the occasional S. hirundo, as well as Charadrius alexandrinus and some T. tadorna.
Non-bird biodiversity: None known to BirdLife International.
Pressure/threats to key biodiversity
Threats include poaching and disturbance resulting from a road which crosses the western edge of the site and from feral dogs. The spread of tourist developments along the shore, coming southward from Hammamet and northward from Sousse, two of Tunisia’s principal tourist centres, is bound to impact the site unless some habitat conservation measures are taken.