The influence of thermoregulatory demand on contact creching behaviour inAdelie Penguin chicks

摘要

(1) We tested the hypothesis that contact behaviour in Adelie Penguin (Pygoscelis adeliae) chicks of creching age is strongly influenced by thermoregulatory demand. (2) Estimated thermoregulatory costs (% minimal metabolic rate) for early creche stage (1 kg) chicks were much higher (13.4-121.0%) than for late creche (3 kg) chicks (0-45.1%). The incidence of contact behaviour was high during early creche, but uncommon during late creche. (3) Both the percentage of early creche chicks forming contact groups and the mean number of chicks per group increased significantly as thermoregulatory demand increased. (4) Thermoregulatory costs were significantly higher when late creche chicks exhibited contact behaviour than when they did not. (5) Contact behaviour in Adelie Penguin chicks therefore appears to perform a thermoregulatory function and probably confers important energy savings in terms of maintaining a favourable daily energy budget and Maximum fasting duration.