Non-vocal mutual courtship communication in a socially monogamous songbird

Abstract

Estrildid finches are one of the most studied songbird families for acoustic communication. They often combine their songs with body movements (i.e., dance) during courtship. Past literature has provided detailed descriptions of dance components, but there are still few empirical studies on the behavioral mechanisms and functions of dancing compared to songs. Our study species, blue-capped cordon-bleus (Uraeginthus cyanocephalus), perform characteristic dance displays in both sexes. During courtship, they repeatedly bob up and down and sing songs several times. We have previously found that they perform human tap-dance-like high-speed movements, tapping their legs on the perch two to six times in a single bobbing. Their behavior is interesting not only because both sexes perform almost the same display but also because their dance movements can produce sounds and vibrations. Here we present our findings on the dance behavior of cordon-bleus in both captive and wild conditions. Our studies suggest that the sounds and vibrations by dancing can function as communication signals and have multifaced functions depending on the social and environmental contexts. It underscores the importance of studying the non-vocal aspects of songbird courtship displays towards a better understanding of animal communication and its complexities.