Diagnostic écologique du Parc National lchkeul (Tunisie) après la construction des barrages: cas des oiseaux d'eau

A dramatic decline of nearly 40 % in waterbird abundance—down to about 60 000 individuals—has been directly linked to the construction of three upstream dams that reduced freshwater inflow and doubled lake salinity, from an average of 13 g l−1 before dams to 27 g l−1 after. This increase in salinity severely depleted Potamogeton and Scirpus populations, key food sources for herbivorous waterbirds such as ducks and coots, leading to their seasonal restriction to small river mouths and eventual disappearance by late autumn. The study analyzed monthly species richness and abundance data from 2001–2004, revealing significant seasonal variation with peaks in November and December (up to 50 000 individuals) and troughs in summer (as few as 1 500). A total of 71 waterbird species were recorded, with herbivores dominating the community but showing the lowest peak abundance since systematic monitoring began. The research supports the hypothesis that freshwater diversion and increased salinity are primary drivers of ecological change, threatening both vegetation and waterbird populations in Ichkeul National Park.

Hamdi, N., Touihri, M., & Charfi-Cheikhrouha, F. (2012). Diagnostic écologique du Parc National lchkeul (Tunisie) après la construction des barrages: cas des oiseaux d’eau. Revue d’Écologie (La Terre et La Vie), 67(1), 41–62. https://doi.org/10.3406/revec.2012.1619