Dynamic fine-scale sea-icescape shapes adult emperor penguin foraging habitat in East Antarctica

Sara Labrousse1, Alexander D. Fraser2, Michael Sumner3, Takeshi Tamura4, David Pinaud5, Barbara Wienecke6, Roger Kirkwood6, Yan Ropert-Coudert5, Ryan Resinger5, Ian Jonsen7, Rick Porter-Smith8, Christophe Barbraud9, Charles André Bost10, Rubao Ji11 and Stephanie Jenouvrier1, (1)Woods Hole Oceanographic Institution, Woods Hole, MA, United States, (2)University of Tasmania, Institute of Marine and Antarctic Studies, Hobart, TAS, Australia, (3)Australian Antarctic Division, Channel Highway, Kingston, Tasmania 7050, Australia, TAS, Australia, (4)National Institute of Polar Research, Tokyo, Japan, (5)Centre d’Etudes Biologiques de Chizé, France, (6)Australian Antarctic Division, Kingston, TAS, Australia, (7)Macquarie University, Biological Sciences, Sydney, NSW, Australia, (8)University of Tasmania, Hobart, TAS, Australia, (9)Centre d’Etudes Biologiques de Chizé (CEBC), UMR 7372 Université de la Rochelle-CNRS, Villiers-en-Bois, France, (10)Centre d’Etudes Biologiques de Chizé (CEBC), UMR 7372 Université de la Rochelle-CNRS, France, (11)Woods Hole Oceanographic Institution, Woods Hole, United States
The emperor penguin, an iconic species threatened by projected sea-ice loss in Antarctica, has long been considered to forage at the fast ice edge, presumably relying on large/yearly-persistent polynyas as their main foraging habitat during the breeding season. Using newly developed fine-scale sea-icescape data and historical penguin tracking data, this study for the first time suggests the importance of less-recognized small openings, including cracks, flaw leads and ephemeral short-term polynyas, as foraging habitats for emperor penguins. The tracking data retrieved from 47 emperor penguins in two different colonies in East Antarctica suggest that those penguins spent 23% of their time in ephemeral polynyas and did not use the large/yearly-persistent, well-studied polynyas, even they occur much more regularly with predictable locations. These findings challenge our previous understanding of emperor penguin breeding habitats, highlighting the need for incorporating fine-scale seascape features when assessing the population persistence in a rapidly changing polar environment.