The acoustic strategies of male Rhacophorus moltrechti in reproductive competition

• Main Authors: Ching-Chi Chen, 陳清旗
• Other Authors: Ping-Chun Lucy Hou
• Format: Others
• Language: en_US
• Published: 2005
• Online Access: http://ndltd.ncl.edu.tw/handle/79808418012887334790

碩士 === 國立成功大學 === 生命科學系碩博士班 === 93 === 　Male anurans modify their call properties according to different contexts in choruses for male-male competition and female attraction. Male R. moltrechti produce advertisement calls consisted of two phases with slow and fast phase rates. In this study, acoustic responses of male R. moltrechti to various conspecific advertisement calls, differing in complexity (number of notes in the phases), call rate, and sound pressure level, were investigated by playback experiments. Males responded to increasing call complexity by adding notes to slow phase and increasing overlap with the stimuli. Males responded to increasing call rate by adding notes to slow phase and increasing their own call rate, but avoiding overlap with the stimuli. In addition, males responded to increasing sound pressure level by adding notes to fast phase and increasing call rate, loudness, and overlapping with the stimuli. All these responses by male R. moltrechti probably signal a stronger aggression to the competitor and increase the caller’s attractiveness to the females. The results indicate that male R. moltrechti can adjust their call properties according to the rival’s acoustic property, which may be correlated with the risk levels of losing attraction to females. These adjustments probably conserve their energy expense and maximize their chances of mating success.