The role of vocal communication in the biology of fledgling and juvenile kea (nestor notabilis) in Aoraki/Mount Cook National Park (2004)
AuthorsArmstrong, Debbie Mareeshow all
The kea is the only parrot species in the world to include the true alpine environment as part of their habitat. Survival in these harsh alpine conditions has been hypothesised to be the cause of the generalist behaviour of kea, leading to their heightened explorative behaviour and curiosity. Kea are also widely regarded as being extraordinarily intelligent. It is their intelligence that suggests that kea may possess a sophisticated communication system. I conducted a study exploring the potentially complex vocal repertoire of the kea. My study was conducted with wild population of banded juvenile and fledgling kea in Aoraki/Mount Cook National Park between February 2003 and April 2004. I obtained 449 vocalisations from 16 identified and several unidentified kea. The results of this study confirmed that the vocal repertoire of the kea is exceptionally large for a parrot species, encompassing over 17 vocalisations. This study revealed five vocalisations previously undescribed in the kea repertoire and showed for the first time that vocal repertoire of immature kea may be different to the repertoire of adult kea. Two possible gender specific vocalisations were also revealed. The study of apparent vocal responses revealed that kea appear to be able to identify vocalisation types and respond accordingly using combinations of increasingly complex vocalisations. This is also the first study to take advantage of the similarity between human and parrot vocal systems for the kea, by utilizing powerful human speech analysis software. The results of this analysis allowed the identification of subtle differences in kea vocalisations, including the presence of graded signals, not identifiable by use of spectrogram analysis.