Identification of fledgling and juvenile Kaka ( Nestor meridionalis ) | Notornis and Birds New Zealand

Notornis

Moorhouse, RJ¹  Greene, TC¹ 

关键词: growth;    juvenile identification;    Kaka;    Nestor meridionalis;   

DOI  :  

学科分类：动物科学

来源: Ornithological Society of New Zealand Inc.

【 摘 要 】

Kaka (Nestor meridionalis) less than one year old can be distinguished from older birds by a pale ring of skin around the eye (periophalmic ring). In birds less than five months old this has a yellow tinge, as does the cere, gape and the soles of the feet. A further distinguishing feature of Kaka between three and six months of age are protruding rachides (feather quills) on the tips of the tail feathers. On Kapiti and Little Barrier Islands, most Kaka nestlings fledge in February and receive food from their parents until June or July. Fledglings can often be detected during this period by their conspicuous and frequent food-begging behaviour. Juvenile characteristics in the Kaka persist for a much shorter period than in the Kea (N. notabilis), its sole extant congener. The loss of juvenile characteristics prior to sexual maturity suggests that juvenile Kaka becomes socially independent of adults earlier than Kea, presumably because of more readily obtainable food sources in their environment.

【 授权许可】

Unknown