Anthropogenic Effects on Amphibian Diversity and Habitat Similarity in the Yoko Forest Reserve, Democratic Republic of the Congo

Anthropogenic disturbance of natural environments has negative impacts on biodiversity. Amphibians are especially sensitive to deforestation, and there is a high rate of this phenomenon in the Democratic Republic of the Congo. We studied the effects of this modification of forest ecosystems on the diversity of amphibians in the Yoko Forest Reserve. During twenty-four field sampling campaigns organized over a period of twelve months, amphibians were collected from nocturnal surveys supported by three techniques: visual spotting using a headlamp, systematic searching of habitats and acoustic hearing of vocalizations. Twelve sampling sites were chosen, and three habitats were explored at each site. Of these three habitats, one is the undisturbed habitat (primary forest), and two are disturbed habitats (fallow and field). Amphibian abundance, species richness, diversity, evenness and density were compared between these two types of habitat. A total of 4443 amphibians in 10 families, 17 genera and 33 species were recorded throughout the study area. Abundance, species richness and relative density were significantly higher in non-disturbed habitats than in disturbed habitats. On the other hand, primary forest is less diverse than fallow, but not significantly. It is, however, significantly more diverse than the field. The undisturbed habitat is also characterized by lower evenness than the disturbed habitats, with which it shares low similarities. The species Amnirana albolabris, Phrynobatrachus auritus, Leptopelis notatus, Leptopelis millsoni, Xenopus pygmaeus, Hyperolius platyceps, Leptopelis calcaratus, Leptopelis christyi, Leptopelis ocellatus, Arthroleptis tuberosus, Ptychadena perreti, Amietia nutti, Arthroleptis variabilis, Cardioglossa leucomystax, Phrynobatrachus perpalmatus and Chiromantis rufescens were recognized, in order of importance, as primary forest indicators according to the results of this study. All these differences between the two habitat statuses (undisturbed and disturbed) confirm the negative effects of natural habitat alteration on forest amphibians.