Waterbird Population Estimates in Hadejia-Nguru Wetlands: Analysis of a Five-Year Monitoring Program

The Hadejia–Nguru Wetlands (HNWs) is among the most important wetlands in sub-Saharan Africa by supporting an important number of waterbird populations and human livelihoods. This paper reports the population of waterbird species counted within a five-year survey; 2015, 2016, 2018, 2019 and 2020. The data were analyzed using the Pivot Table function in Microsoft Excel and R programming language. Results reveal 1,139,666 individual birds of 93 species from 19 families over the survey period. The average waterbird population was 40,330 individuals in 2015 (species richness, S, 64), 33,281 in 2016 (S = 61), 49,950 in 2018 (S = 64), 40,773 in 2019 (S = 72), and 63,598 in 2020 (S = 70). The bird families with the highest bird species were Accipitridae (18 species), followed by Ardeidae (11 species), then Anatidae and Scolopacidae (10 species each). The three waterbird species with the most population were Dendrocygna viduata , 443, 652 (39%) followed by Spatula querquedula 234,074 (21%) and Calidris pugnax 168,142 (15%), accounting for 75% of the total individual birds recorded. Generally, the waterbird population in the HNWs did not show declines over the survey period even though there was evidence of fluctuation. Four species of conservation concern were recorded; Beaudouin’s Snake Eagle Circaetus beaudouini (Vulnerable), Hooded Vulture Necrosyrtes monachus (Critically endangered), Martial Eagle Polemaetus bellicosus (Vulnerable) and Pallid Harrier Circus macrourus (Near Threatened). The majority of the waterbird populations had a global decreasing population trend, indicating the need for urgent conservation intervention locally. More monitoring and census at a different season of the year and increased awareness of conservation in the wetland would certainly help in the long-term conservation of waterbirds and their habitats. This is especially true because of the significance of the HNWs as a wintering ground and stopover site for Afro-Palearctic migratory waterbirds.