Response of male bluethroats Luscinia svecica to song playback: Evidence of territorial function of song and song flights

Abstract

Male bluethroats (Luscinia svecica) have a complex song which is often delivered in the form of song flights. Earlier studies, based upon timing of display, indicate that the chief function of the bluethroat's song was for mate attraction/retention, but the possible territorial function of the song has not been rigorously tested. In song playback experiments performed in the territories of 26 males, a significant increase in song and song flight activity relative to pre-playback levels was observed among males who were not seen to have females in their territories. However, mated males who were seen to be guarding females did not respond to song playbacks, but remained silent, closely guarding their mates. Hence, despite the earlier evidence showing that the bluethroat's song is used to attract a mate, these results suggest that it functions in male-male competition during the pre-mating period and may, in this way, improve a male's mating success.