A Study on Bird Diversity and Abundance in a Lowland of the Centre Region of Cameroon (Ekoko II village) confirm High Diversity in the Congo Basin Forest and a Greater Dominance in the Distribution of Species in the Lowlands

Abstract

Cameroon is one of the six Congo Basin Forest countries. The Centre region of Cameroon (Central Africa) is a relictual site in which several expeditions by naturalist ornithologists have permitted to describe many new birds’ specimens. Only in recent years, very few bird surveys have been conducted in this area to get an idea about the new or old taxa that make up this region. We conducted a bird survey in a locality of the Centre region of Cameroon, Nsimalen district of Mfou (more precisely in the Ekoko II village) to investigate the avifauna as well as to explore the abundance, diversity and distribution and eventually their reasons. To obtain the abundance of bird species, we used the mist-netting method and captured birds during eleven months. In order to analyse diversity and distribution of this avifauna in their life environment, we performed analyses with SAS/STAT and PAST software. We caught 227 individuals belonging to 24 birds’ families. Compared with previous surveys in this region, we newly recorded one family (Phylloscopidae), one genus (Phylloscopus) and two species: Phylloscopus bonelli and Criniger ndussumensis. In the Ekoko II avifauna, many are sedentary but there is also a great mixture of birds described as seasonal migrants, intra-African migrants, residents, etc. Values of the obtained diversity indexes show that the Nsimalen village exhibits a great avifaunistic diversity. Our results show an absence of the supremacy of one species (H’=3.14) and the value of the Equitability index (J’=0.80) supports an equal distribution of the individuals. Then the pattern of distribution of the species also appears to lean on ecological factors and in this case, the vegetation which would have played a main role in their distribution with a mix of specialists and generalists birds or even migratory birds due to the abundant vegetation. Otherwise, our study also reveals that the composition and structure of the vegetation play a main role in the variety of bird species at least at the local scale. Compare to mountainous areas, our study establishes some similarities in the pattern of distribution of the species between mountain areas and lowlands but diversity has clearly been higher in the mountains while dominance is more pronounced in the lowlands.