Fluctuations in Adélie penguin prey size in the mid to late Holocene

• Main Authors: Jenny D. Mcdaniel, Æ Steven, D. Emslie, Northern Marguerite Bay, Antarctic Peninsula
• Other Authors: The Pennsylvania State University CiteSeerX Archives
• Format: Text
• Language: English
• Published: 2002
• Subjects: Antarctic; Antarctic Peninsula; Arctic; Ginger Islands; Lagoon Island; Marguerite; Marguerite Bay; Antarc*; Climate change
• Online Access: http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.503.9543; http://people.uncw.edu/emslies/research/McDaniel and Emslie 2002.pdf

Abstract We investigated temporal changes in Adélie penguin prey size in northern Marguerite Bay, Antarctic Peninsula, through excavations of three abandoned and one active colony at Lagoon (6735¢S, 6816¢W) and Ginger Islands (6745¢S, 6841¢W), respectively, in aus-tral summer 1999/2000. Radiocarbon dates on penguin bones and eggshell fragments collected at each site in-dicate that Lagoon Island was first occupied after 6000 BP and Ginger Island near 2275 BP. Identifiable non-krill prey remains (otoliths and squid beaks) were recovered from ornithogenic soils at all sites, with Ant-arctic silverfish (Pleuragramma antarcticum) and squid (Psychroteuthis glacialis) being the most abundant spe-cies represented in the deposits. Estimated mean stan-dard lengths and mantle lengths of these two prey taxa, based on regressions with otolith and beak measure-ments respectively, indicate that Adélie penguins primarily select these prey within a mean size range of 95–117 mm. Prey size also varied significantly across seven occupation periods from 6000 BP to the present, but did not correlate with climate change.