No survival of native larval frogs in the presence of invasive Indian bullfrog Hoplobatrachus tigerinus tadpoles

Abstract

Invasive amphibians have considerable negative impacts on recipient ecosystems, however, impact has been assessed for only a few species, limiting risk assessments. In particular, the impact of invasive anurans with carnivorous tadpoles have not been examined thoroughly. The Indian bullfrog (Hoplobatrachus tigerinus), native to the Indian sub-continent, is rapidly invading the Andaman archipelago, Bay of Bengal after its recent introduction. We aimed to evaluate the effect of carnivorous H. tigerinus tadpoles on two species of endemic anuran tadpoles Microhyla chakrapanii and Kaloula ghoshi, in a mesocosm experiment. Rapid predation by larval H. tigerinus resulted in no survival of endemic frog tadpoles. Survival of H. tigerinus was density-dependent. The study is timely in elucidating the impact of invasive larval H. tigerinus on native anurans and substantiates the need to manage invasive populations (or potential incursions) of the species on the Andaman archipelago and elsewhere.