No abstract

The habitats and ecosystems of the Mediterranean Sea are of prime strategic interest both ecologically and economically. The Ferruginous duck, a species widely distributed in Africa, Europe and Asia, these numbers have experienced declines and changes in distribution in recent decades. The primary reasons for these declines are mainly due to habitat degradation and loss and hunting for local consumption .

To date, Algeria has twenty-two wetlands designated as Important Bird Areas (IBA). However, other wetlands are also eligible for this network but have not yet been classified due to a lack of comprehensive studies demonstrating their ornithological importance. In this study, we are interested in the Boussedra marsh, located on the Algerian coast in the far northeast. IBA categories A1 and A4i were found to be significant, confirming the international importance of this wetland for waterbirds. Five species inhabiting the site are listed as globally threatened on the IUCN red list, namely, Oxyura leucocephala (Endangered), Aythya nyroca (Near Threatened), Vanellus vanellus (Near Threatened), Aythya ferina (Vulnerable) and Marmaronetta angustirostris (Vulnerable). Interestingly, Oxyura leucocephala was recorded with more than 10% of the world's population. Overall, the avian community of Boussedra inventoried between September 2015 and August 2018, has reached a diversity of 42 species, i.e., one-third of the national aquatic avifauna, consisting mainly of surface ducks, Rallids, waders, gulls and raptors, making it one of the ten most diverse wetlands in the country. Although the monthly numbers of waterbirds in the marsh are low compared to the large Algerian sites (< 5000 individuals), they are still among the most important locally. Boussedra is a real wintering area, but it is also home to a diverse nesting population of 20 species, including four that are globally threatened according to the IUCN Red List, making it one of the most important nesting areas for waterbirds in Algeria.