ENERGETIC COSTS OF RAISING PYGOSCELID PENGUIN CHICKS

Energy requirements of resting Adelie (Pygoscelis adeliae), Gentoo (P. papua) and Chinstrap (P. antarctica) penguin chicks were determined w ith respect to body mass via respirometry in Antarctica. Resting metab olic rates of all Pygoscelid penguin chicks were similar (ANOVA p = 0. 91) and best described by E = 0.0096 M0.98 (n = 24, r2 = 0.97), where E is power (W) and M is mass (g). Using the results obtained here and data published in the literature, I determined a) the amount of food n eeded from hatching to fledging as 29.8, 31.7 and 56.4 kg per chick fo r Adelie, Chinstrap and Gentoo penguins, respectively and b) the avera ge amount of food left daily to the parent after feeding the brood thr oughout the breeding period. Parents keep only a minimum of food for t hemselves just prior to the time when chicks begin forming creches. Th ereafter, nest relief intervals are increased, and the amount of food parents can keep for themselves rises. The results of both models are discussed with respect to available data on Pygoscelid penguin food re quirements.