An experimental test of host song mimicry as a species recognition cue among male brood parasitic indigobirds (Viduaspp.)

Abstract

ABSTRACT Obligate brood parasites, which typically lack reliable interactions with conspecifics early in life, acquire species recognition cues by mechanisms other than imprinting on parents and siblings. The African indigobirds (Vidua spp.) are exceptional among brood parasites in that learning and mimicry of host vocalizations play an integral role in the social behavior of the parasites. Male indigobirds have impressive vocal repertoires featuring chatter calls, host mimicry, and complex non-mimicry songs. While chatter calls are similar, sympatric indigobirds are distinguished both by their mimicry of different hosts and by unique repertoires of non-mimicry songs. A previous playback experiment showed that male indigobirds respond differentially to natural singing (i.e. playbacks including host mimicry, chatter, and complex non-mimicry) of sympatric conspecifics and heterospecifics, but the relative role of host mimicry and complex non-mimicry in species recognition remains unknown. We addressed this ...