Variability in foraging behaviour of chick-rearing macaroni penguins Eudyptes chrysolophus and its relation to diet

Flexibility in foraging behaviour and diet are characteristics of many penguin species. While these 2 aspects of foraging ecology are presumably tightly coupled, the connection between them is rarely examined directly. Using time-depth recorders and satellite telemetry we documented the foraging behaviour of 43 chick-rearing macaroni penguins Eudyptes chrysolophus at Heard Island. We also compared these behavioural data with prey recovered from the stomach contents of each tracked bird. During guard stage, foraging trips were significantly shorter (average duration = 23 +/- 18 h, range = 47 +/- 40 km) compared to creche stage (average duration = 115 +/- 112 h, range = 169 +/- 102 km). Creche stage trips also included significantly more shallow dives that appear to be related to travel (39% of dives