Collared Dove Responses to Playback: Slaves to the Rhythm

Temporal features are the most important parameters for differentiating among the perch coo vocalizations of doves in the genus Streptopelia. The role of temporal features in inducing territorial responses was studied for one of these species, the collared dove (S. decaocto), using playback experiments. The playback stimuli consisted of manipulated coos, which were tested against a preplayback period and against unmanipulated control coos. In a first set of three manipulations, the temporal structure was altered by removing an element from the species-typical three-element coos. A coo lacking the third element, which is a naturally occurring variant, was as equally effective as the control in eliciting a territorial response. The same applied to a coo lacking the second and longest element. In contrast, a coo lacking the first element did not elicit a significant increase in territorial activities compared with the preplayback period, and there was a significant reduction in response compared with the control coo. A second set of two manipulations concerned changes in the species-typical rhythm. The two variants both led to a significant reduction in response compared with the normal rhythm, although they were still effective in eliciting an increase in activities compared with the preplayback period. The results indicate that the rhythm of territorial cooing plays an important role in communicating to conspecifics. As different sympatrically living dove species differ in particular in temporal features, rhythm may be an important cue for species recognition and may contribute to reproductive isolation.