Microhabitat segregation of two coexisting tadpole species on Emei Mountain

Understanding mechanisms determining the coexistence between different species is one of the key issues in community ecology and biodiversity conservation. Microhabitat segregation is a way for species to coexist, which reflects the specific habitat selection of coexisting species in a finer spatial scale. Despite quantitative studies have been conducted to investigate the microhabitat segregation of coexisting species, this type of studies was not often performed on tadpoles. In this study, we assessed the habitat selection of two coexisting tadpoles (Quasipaa boulengeri and Leptobrachium boringii) in a stream on Emei Mountain, China. Our results demonstrated that L. boringii and Q. boulengeri tadpoles occupied different microhabitats. Specifically, Q. boulengeri tadpoles preferred deep, narrow, and weak acid stream segments with slow current velocity and low value of conductivity, while L. boringii tadpoles tended to occur in a wide, shallow water bodies with relatively higher pH, conductivity, and current velocity. Overall, our study supported the Hutchinson's niche concept, showing that at least one dimension of niche differentiation (i.e., microhabitat) occurred between coexisting tadpole species.