Preliminary data on waterbirds of the Garaet Hadj-Tahar (Skikda, north-east Algeria). The results are presented of waterbird counts carried out weekly from August 2005 to February 2007 at the Garaet Hadj-Tahar, in north-east Algeria (36°51'N 07°15'E). In total, 52 species representing 15 families were recorded at this site, which is part of an Important Bird Area (IBA) and a Ramsar Site. Amongst the 11 breeding species, two are of conservation concern: White-headed Duck Oxyura leucocephala, classified as globally Endangered (up to 89 individuals present; three nests found), and Ferruginous Duck Aythya nyroca, which is Near Threatened (27 breeding pairs, 14 nests found; 800 individuals wintering in November-December 2006). In winter, ducks are well represented (12 species, with a maximum of c.10,000 individuals in January 2007), as well as Common Coots Fulica atra (c.5,000 individuals).