Video evidence of song in a nestling Yellow-rumped Tinkerbird (Pogoniulus bilineatus) supports innate song development in Piciformes

Most bird species learn their songs by copying those of their parents or those they hear from their natal surroundings. Most non-oscine birds, however, lack the forebrain structure implicated in song learning and are thought to develop songs innately. Yet, evidence of early song development in non-oscines is scant. Here we report on vocalizations emitted by a nestling Yellow-rumped Tinkerbird (Pogoniulus bilineatus) that were recorded by camera trap at a nest cavity in KwaZulu-Natal, South Africa. We obtained 32 video recordings of a nestling singing, from which we measured temporal and spectral characters and compared them with those of adult song. Rudimentary nestling song was remarkably similar to adult song. differing slightly in frequency and the temporal patterning between songs, but with the same temporal patterning within songs. Tinkerbirds thus can sing within 2 weeks post-hatching, supporting the premise that songs develop early and innately in a piciform.