Vocal Strategies in Confronting Interfering Sounds by a Frog from the Southern Temperate Forest, Batrachyla antartandica

Abstract

Animals are communicating by sound face interference from biotic and abiotic sources. Contrasting strategies have been reported in different taxa in the presence of prolonged noises, but in particular, interactions among acoustically active species have been studied to a very limited extent. In addition, reactions of a single species to interferences having contrasting structural patterns have not been explored systematically. The vocal responses of 16 male frogs Batrachyla antartandica from the temperate austral forest in Chile were tested with conspecific calls and with the calls of two sympatric species: B. taeniata and B. leptopus, broadcast at amplitudes of 73, 79, 85, 91, and 97dB peak sound pressure level (SPL). Also, the vocal activity of the subjects during exposure to a 3-min continuous broadband noise presented at 67dB root mean square (RMS) SPL was monitored. The subjects gave significantly higher responses to the conspecific relative to the heterospecific calls but increas