Playback experiment shows no evidence for vocal learning in titipounamu nestlings ( Acanthisitta chloris )

A recent reshuffling in the avian phylogeny indicates that New Zealand wrens and songbirds share a close common ancestor with parrots – making New Zealand wrens an excellent group to test for vocal learning. The New Zealand wrens have previously been classified as vocal non-learners, but their vocal learning ability has never been experimentally tested. Here, we explore the potential presence of vocal learning in one species of New Zealand wren, the titipounamu (Acanthisitta chloris). We expose nestlings to synthetic playback stimuli that simulate adult feeding calls and determine whether the nestlings altered their calls after exposure to the playback stimuli. We found that experimental nestlings did not alter their calls towards the playback stimuli. While this indicates that no vocal imitation occurred during the nestling period, other developmental stages should be tested for vocal learning, particularly during the fledgling or first year adult phase.