Contrôle de l'inondation dans le delta du Sénégal : Les Anatidés s'adaptent-ils aux nouvelles situations environnementales ?

The dyking of the Senegal delta and the dam on the river have modified the wetlands and their use by duck populations. Three afro-tropical species and two paleartic species have continued to frequent the delta in hig, although variable, numbers, despite the decreasing quality of their environment (Fulvous Whistling Duck Dendrocygna bicolor, White-faced Whistling Duck Dendrocygna viduata, Egyptian Goose Alopochen aegyptiacus, Pintail Anas acuta, Garganey Anas querquedula). Two other paleartic species showed marked variation in numbers (huge increase for the Shoveler Anas clypaeta, near disapperance for the Teal Anas crecca). Three African species showed a negative trend (Spur-winged Goose Plectropterus gambensis, and even more markedly the Comb Duck Sarkidiornis melanotos and the African Pygmy Goose Nettapus auritus). The conservation or restoration of these Anatidae populations implies that the governemental bodies in charge of the protected areas be given the means for implementing such aims. Moreover the entire lower valley of the Senegal river must be taken into account in order to consider all the sites potentially favorable to waterbirds, even those that are unprotected (such as the lake of Aleg in Mauritania).