How animals distribute themselves in space: energy landscapes of Antarctic avian predators

• Published in: Movement Ecology
• Main Authors: Juan F. Masello, Andres Barbosa, Akiko Kato, Thomas Mattern, Renata Medeiros, Jennifer E. Stockdale, Marc N. Kümmel, Paco Bustamante, Josabel Belliure, Jesús Benzal, Roger Colominas-Ciuró, Javier Menéndez-Blázquez, Sven Griep, Alexander Goesmann, William O. C. Symondson, Petra Quillfeldt
• Format: Article in Journal/Newspaper
• Language: English
• Published: BMC 2021
• Subjects: Antarctica; Breeding success; Chinstrap penguin Pygoscelis antarcticus; Energy costs; Energy landscapes; Gentoo penguin Pygoscelis papua; Biology (General); QH301-705.5; Antarctic; The Antarctic; Antarctic Peninsula; Livingston Island; Antarc*; antarcticus; Chinstrap penguin; Gentoo penguin; Pygoscelis papua
• Online Access: https://doi.org/10.1186/s40462-021-00255-9; https://doaj.org/article/323fb4002141494ab84d2115b0278b44

Abstract Background Energy landscapes provide an approach to the mechanistic basis of spatial ecology and decision-making in animals. This is based on the quantification of the variation in the energy costs of movements through a given environment, as well as how these costs vary in time and for different animal populations. Organisms as diverse as fish, mammals, and birds will move in areas of the energy landscape that result in minimised costs and maximised energy gain. Recently, energy landscapes have been used to link energy gain and variable energy costs of foraging to breeding success, revealing their potential use for understanding demographic changes. Methods Using GPS-temperature-depth and tri-axial accelerometer loggers, stable isotope and molecular analyses of the diet, and leucocyte counts, we studied the response of gentoo (Pygoscelis papua) and chinstrap (Pygoscelis antarcticus) penguins to different energy landscapes and resources. We compared species and gentoo penguin populations with contrasting population trends. Results Between populations, gentoo penguins from Livingston Island (Antarctica), a site with positive population trends, foraged in energy landscape sectors that implied lower foraging costs per energy gained compared with those around New Island (Falkland/Malvinas Islands; sub-Antarctic), a breeding site with fluctuating energy costs of foraging, breeding success and populations. Between species, chinstrap penguins foraged in sectors of the energy landscape with lower foraging costs per bottom time, a proxy for energy gain. They also showed lower physiological stress, as revealed by leucocyte counts, and higher breeding success than gentoo penguins. In terms of diet, we found a flexible foraging ecology in gentoo penguins but a narrow foraging niche for chinstraps. Conclusions The lower foraging costs incurred by the gentoo penguins from Livingston, may favour a higher breeding success that would explain the species’ positive population trend in the Antarctic Peninsula. The lower ...