Distribution of breeding waterbirds in relation to wetland characteristics in the Oued Righ valley in the Algerian Sahara

Abstract

Abstract In the framework of this study 14 breeding species were identified in the wetland complex of the Oued Righ valley in the Algerian Sahara. Six species of breeding Anatidae were reported, two of which are classified as vulnerable and threatened, namely, the ferruginous duck Aythya nyroca and the marbled teal Marmaronetta angustirostris. For shorebirds, we noted reproduction of the pied avocet Recurvirostra avosetta, the black-winged stilt Himantopus Himantopus, and the Kentish plover Charadrius alexandrinus in most of the wetlands studied. We report for the first time nesting of the slender-billed gull Chroicocephalus genei at Chott Merouane with 72 pairs recorded during the breeding season 2018. This colony was associated with the larger colony of greater flamingo Phoenicopterus roseus composed of 640 pairs. Principal component analysis (PCA), gathering 69.74% of the information, showed a significant correlation between the distribution of different bird species and the main environmental factors, that is, vegetation, water surface area, water depth, and salinity, and a strong correlation between the species of Annatidae and Rallidae, which are associated with less-saline environments rich in vegetation and deep water, with the exception of shelducks, which prefer large surface areas with less-dense vegetation and more holomorphic water. For the shorebirds such as R. avosetta and H. himantopus, there was a clear preference for large wetlands with shallow water and relatively high salinity. A remarkable correlation was also noted for P. roseus, where a strong distribution of breeding populations was observed in areas with the highest salinity levels and a vast surface area.