Modeling the Marine Resources Consumed in Raising a King Penguin Chick: An Energetics Approach

• Published in: Physiological and Biochemical Zoology
• Main Authors: Halsey, L.G., Butler, P.J., Fahlman, A., Bost, Charles-André, Woakes, A.J., Handrich, Yves
• Other Authors: School of Human and Life Sciences, University of Roehampton, United Kingdom, Centre for Ornithology, University of Birmingham Birmingham, North Pacific Universities Marine Mammal Research Consortium, University of British Columbia (UBC), Centre d'études biologiques de Chizé (CEBC), Centre National de la Recherche Scientifique (CNRS), Centre d'écologie et physiologie énergétiques (CEPE)
• Format: Article in Journal/Newspaper
• Language: English
• Published: HAL CCSD 2008
• Subjects: [SDE.BE]Environmental Sciences/Biodiversity and Ecology; [SDE.ES]Environmental Sciences/Environmental and Society; [SDE.MCG]Environmental Sciences/Global Changes; Austral; Southern Ocean; King Penguins
• Online Access: https://hal.archives-ouvertes.fr/hal-00339309; https://doi.org/10.1086/592821

International audience Accurate estimates of penguin energetics would represent an important contribution to our understanding of the trophodynamics of the Southern Ocean ecosystem and our ability to predict effects of environmental change on these species. We used the heart rate–rate of oxygen consumption technique to estimate rate of energy expenditure in adult king penguins raising a chick, in combination with data from the literature on changes in adult mass, chick energy requirements, and prey energy density. Our model estimated a variety of energetic costs and quantities of prey consumption related to raising a king penguin chick during the austral summer. The total energy requirements of a king penguin chick at the Crozet Archipelago from hatching until reaching a mass of 8 kg 90 d later is 271 MJ, representing the consumption of 38.4 kg of myctophid fish. A successfully breeding male requires 0.78 kg d1 of fish during the entirety of the incubation period and 1.14 kg d1 during the subsequent 90 d of chick rearing. Assuming the same energy requirements for females, the estimated 580,000 pairs of king penguins that breed successfully at Crozet each year, together with their chicks, consume a total of around 190,000 tons of fish during the incubation and summer rearing periods combined. If, due to depletion of fish stocks, the diet of breeders and chicks during the summer becomes identical to the typical diet of adults during the austral winter, the mass of prey required by both adults and chicks combined (where the chick still reaches 8 kg after 90 d) would increase by more than 25%.