Growth and survival of chicks in relation to nest attendance patterns of little penguins ( <i>Eudyptula minor</i> ) at Oamaru and Motuara Island, New Zealand

Abstract

Abstract Little penguins breeding on Motuara Island, New Zealand, went on longer foraging trips during the incubation period compared with those breeding at Oamaru, Otago, resulting in higher rates of egg desertion at Motuara (Numata et al. 2000). In this paper, we report on the differences at these two sites in growth and survival of penguin chicks. During the guard stage at both study areas, parents alternated chick‐brooding duties on average every day, and lost 1–2% of their body mass after every trip. However, the duration of the guard stage was significantly shorter at Motuara (15.1 ± 1.0 days) than at Oamaru (20.0 ±1.0 days). Body condition of parents was poorer at Motuara than at Oamaru. The poorer food supply available to parents during chick rearing probably caused the lower growth rates and higher risks of desertion and starvation of chicks observed at Motuara.