The incidence of abnormalities in the fire-bellied toad, Bombina orientalis, in relation to nearby human activity

Abstract

Declines in amphibian populations are occurring worldwide, and have been attributed to many factors, including an­thropogenic environmental changes. One of the ramifications of such declines is abnormalities in many amphibian spe­cies. A strong association has been detected between human activities and abnormalities in amphibian populations, but studies on this association are largely focused on lentic species. In this study, it was analyzed whether the degree of local human activity was associated with the rate of abnormalities in Bombina orientalis which inhabited lotic environments. We found that the proportions of abnormalities in wild populations of B. orientalis increased, when i) the closest human land use was located within 100 m from the frogs habitat, and ii) the proportion of human land use within a 300-m radius was high. Our findings suggest that human activity has a negative impact on the fitness of nearby amphibian populations, and that wild populations very close to human-induced disturbance are affected.