Amphibian Herpetofaunal Study of the Niger Delta Region, Nigeria

Abstract

The Niger Delta region in Nigeria is one of the world’s largest wetlands and a host to a rich diversity of amphibian species which was  investigated. Research studies were undertaken during the wet and dry seasons of the years 2022 and 2023 on three survey sites (each  about 90,000m2) selected from each State in which amphibian samplings were conducted. There were a total of 1,647 individuals  belonging to 43 species, 10 Genera and 15 Families. In Delta State and Bayelsa State, 42 species (97.7%) and 35 species (81.4%) were  recorded respectively. However, more individuals [846(51.4%)] were recorded for Bayelsa State than Delta State [801(48.6%)]. In Delta  State, the species with the highest individuals recorded was Hymenochirus sp (7.7%) followed by Amnirana albolabris (5.7%) while the  least was Ptychadena retropunctata (0.2%). The highest individuals were recorded for Hymenochirus sp (7.6%) followed by  Phrynobatrachus calcaratus (6.4%) while the least were Leptopelis boulengeri, L. modestus and Ptychadena aequiplicata each having 6  (0.7%) individuals in Bayelsa State. In total, Hymenochirus sp and Xenopus sp had the highest individuals recorded in both States  combined. Only about 27.9% of species recorded in the Niger Delta were not observed in the Southwestern and Southeastern regions of  Nigeria. The amphibian species richness was not statistically different between Delta and Bayelsa States (P=0.74, df=1, F=0.1059). The  diversity indices showed that Simpson, Shannon and Margalef indices were higher in Delta state than Bayelsa State respectively (0.9651, 0.9611; 3.518, 3.378 and 6.132, 5.044). Different population of species were observed in various microhabitats based on habitat  adaptability. The Niger Delta region is a biome of great amphibian diversity and it is imperative to establish environmental factors that  will support the presence of amphibian population and ultimately their conservation. This study has provided important information  about some aspects of the diversity and ecology of amphibians in the Niger Delta region and these data would help conservation- oriented bodies to make more informed decisions.