Abundance and Diversity of Wetland Birds: The Case of Dinder National Park, Sudan

This study was conducted in Dinder National Park (Sudan). Patterns of bird species diversity, richness, and abundance were documented in four wetland areas inside Dinder National Park, including Ras Amir, Grerisa, Abdel Ghani, and Dabkara Mayas (meadows) during the dry seasons starting 2014 through 2016, and, diversity over this period was badly eroded and under serious threats. Timed-species count (TSC) technique was used for counting birds. Rarefaction curves combined with nonparametric estimators of species richness were used to extrapolate species richness beyond the collected data. The Shannon (H') diversity index and the Simpson (D) index and the evenness index of Pielou (J') were used to assess alpha diversity and diversity within and between sites, respectively. Finally, chi-square goodness of fit test was used to test the H₀ that bird species frequencies at each site were equally proportional and their mean numbers across the four sites were not significantly different. Sampling efforts of over 90% was attained in each of the four study sites. A total of 203 bird species about 145 (71%) of which were wetland birds, all belonging to 33 families and 11 orders, were identified from a set of 3753 individuals. The mean number of wetland birds was generally low at all the Mayas except at Ras Amir Maya where some species had relatively higher mean number. The orders Anseriformes (especially Anatidae), Charadriiformes (especially Jacanidae and Charadriidae), Ciconiiformes (especially Ardeidae, Threskiornithidae, and Ciconiidae), Coraciiformes (especially Alcedinidae), Passeriformes (especially Motacillidae and Ploceidae), and Pelecaniformes (especially Phalacrocoracidae) were the most important, in terms of both abundance and species richness. Diversity indices ranged, in descending order, from Grerisa Maya, Ras Amir Maya, Abd el Ghani Maya to Dabkara Maya. There was no clear trend in terms of bird numbers and abundance between sites, though water-rich Mayas seemed to support more birds than the drier ones. Likewise, certain species were found only in some Mayas but not in others such as African jacana (Actophilornis africanus), African darter (Anhinga rufa), long-tailed cormorant (Phalacrocorax africanus), and allies. This study presents baseline data and contributes in important ways to basic knowledge of wetland biodiversity patterns within Dinder National Park which must be protected because they constitute core areas of great conservation importance.