State-dependent decisions in long-term fasting king penguins, Aptenodytes patagonicus, during courtship and incubation

Using an automatic identification and weighing system, we investigated changes in adult body mass in relation to reproductive behaviour during courtship and incubation in free-living king penguins. Despite stressful nutritional conditions and variability of fast length, the majority of pairs incubated successfully by accumulating large body reserves before fasting, which provided flexibility in fasting strategies. […]

Effects of artificial social stimuli on the reproductive schedule and hormone levels of yellow-eyed penguins (Megadyptes antipodes)

The effects of social stimuli on avian reproductive behaviors such as breeding schedules and courtship behaviors are well known due to numerous field studies. However, studies that have simultaneously examined the effects of social stimuli on reproductive behavior and the mediating endocrine mechanisms have been largely restricted to captive populations, which may not be representative […]

Female polar bears, Ursus maritimus, on the Barents Sea drift ice: walking the treadmill

For animals in dynamic habitats, the contribution of passive (i.e. by wind or current) and active (movements by the animals themselves) displacement determines whether their space use reflects physical or adaptive behavioural processes. Polar bears in the Barents Sea undertake extensive annual migrations in a habitat that is highly dynamic because of continuous sea ice […]