Development of independence in Powerful Owl Ninox strenua fledglings in suburban Sydney

Abstract

 This paper extends previous observations of behavioural development in Powerful Owl Ninox strenua fledglings. The study combines a near-daily visual monitoring program on a pair of owlets in Oatley, suburban Sydney, New South Wales, with corresponding pellet analysis. The fledglings were initially fed on possums, fruit-bats, birds and insects, and first demonstrated independence by disassembling carcasses by themselves. By October, they apparently mimicked the adults’ strategy for capturing insects, and began to chase birds and bats. Behaviours thought to be part of honing their hunting skills—including tearing and ferrying strips of bark, foliage-snatching, and swooping at animals on the ground—were recorded. Such actions intensified during a period when the adults were mostly absent in November and December.