Activity budget for breeding yellow-eyed penguins

Abstract

Abstract Instantaneous scan sampling was used to determine time allocation for various breeding activities of the yellow-eyed penguin (Megadyptes antipodes), from pre-egg phase to post-guard phase. Breeding commences with the pre-egg phase, characterised by the presence of birds ashore during the day. Males are more active at this time, spending more time in an upright posture, preening, or displaying from the nest bowl. Females appear to follow an energy conserving strategy during egg deposition. Two eggs are laid, 3–5 days apart, with fully-prone incubation commencing after the laying of the second egg. Delayed onset of prone incubation is possibly because of low levels of egg predation and the temperate breeding climate. Incubation is shared by both sexes and, energetically speaking, is a period of hiatus; both birds gain weight during this time. Synchronous hatching caused by delayed incubation results in equal-sized siblings. Chick feeding is shared equally by both adults. The period of chick care is...