Distribution, diversity and abundance of anuran species in three different vegetation habitats in southwestern Nigeria

Abstract

The distribution, diversity and abundance of anuran species in three different vegetation habitats of Southwestern Nigeria were investigated. A total mean number of 388 individuals comprising 32 species were observed in the forest, 766 individuals in 28 species were recorded in the fallowed farmland and 278 individuals in 21 species in the savanna. There was significant difference (F_{2, 129} = 3.602) between the numbers of anuran species inhabiting the three vegetation habitats at P < 0.05 as well as significant difference (F_{2, 129} = 5.811)   between the number of individuals of anuran species in the three vegetation habitats (P<0.01). The dominant species in the forest was Arthroleptis variabilis (9.02%) and the least abundant species in the forest were Leptopelis macrotis, Phlyctimantis boulengeri and Nectophryne afra each having 0.26%. Amietophrynus maculatus and A. regularis were both abundant in the fallowed farmland and savanna habitats. The least abundant species in the fallowed farmland was Leptopelis calcaratus (0.13%) while the least abundant in the savanna were Xenopus muelleri and Afrixalus dorsalis each with 0.72%. Thirty percent of anuran species observed occurred in all the vegetation habitats, while 27%, 11% and 7% were restricted to the forest, fallowed farmland and savanna respectively. Most amphibian species were observed and collected between the 18h-21h sampling time frame which confers them as mostly nocturnal in habit. Conservation efforts must be enforced to protect the vegetative structure against unsustainable forest practices in order to protect and maintain the biodiversity status of the region.

Keywords: Distribution, Diversity, Nigeria, Vegetation, Forest and Savanna