Late Holocene variation in the Hard prey remains and stable isotope values of penguin and seal tissues from the Danger I
- PDF / 1,106,695 Bytes
- 12 Pages / 595.276 x 790.866 pts Page_size
- 32 Downloads / 192 Views
ORIGINAL PAPER
Late Holocene variation in the Hard prey remains and stable isotope values of penguin and seal tissues from the Danger Islands, Antarctica Rohit Kalvakaalva1 · Gemma Clucas2,3 · Rachael W. Herman1,4 · Michael J. Polito1,5 Received: 6 December 2019 / Revised: 27 July 2020 / Accepted: 5 August 2020 © Springer-Verlag GmbH Germany, part of Springer Nature 2020
Abstract Ornithogenic soils in Antarctica provide a biological archive of the occupation history and trophic ecology of penguins and other marine species over geological timescales. Hard prey remains and predator tissues, which are well preserved in ornithogenic soils, can act as paleoecological proxies of past environmental conditions. Here we examine ornithogenic soils from an active colony of Pygoscelis spp. penguins on Platter Island in the Danger Islands Archipelago along the northeastern side of the Antarctic Peninsula. We radiocarbon dated penguin tissues from excavated ornithogenic soils and parameterized an age-depth model of penguin occupation history. Hard prey remains were enumerated and recovered Pygoscelis spp. penguin and Antarctic fur seal (Arctocephalus gazella) tissues were analyzed for stable isotopes carbon (δ13C) and nitrogen (δ15N) analysis. The oldest recovered ornithogenic soils at Platter Island date to 502–653 years BP and coincide with the start of a period of increased warming and glacial discharge in the northeastern Antarctic Peninsula. Penguin tissues δ15N values increased between the oldest and youngest dated ornithogenic soils but seal tissues did not. This may indicate that the trophic level of penguins, but not seals, has increased over time, a hypothesis supported by the concurrent increase in the hard prey remains of fish and squid taxa common to penguin diets recovered from ornithogenic soils. Future studies of ornithogenic soils in the Danger Islands Archipelago are warranted to test this hypothesis and assess the potential confounding effects of varying ecosystem isotopic baselines and penguin species composition over time. Keywords Stable isotope analysis · Pygoscelis spp. · Arctocephalus gazella · Paleoecology · Diet
Introduction
Electronic supplementary material The online version of this article (https://doi.org/10.1007/s00300-020-02728-w) contains supplementary material, which is available to authorized users. * Michael J. Polito [email protected] 1
Department of Oceanography and Coastal Sciences, Louisiana State University, Baton Rouge, LA 70802, USA
2
Department of Zoology, University of Oxford, South Parks Road, Oxford OX1 3PS, UK
3
Cornell Lab of Ornithology, Cornell University, Ithaca, NY 14850, USA
4
Department of Ecology and Evolution, 113 Life Sciences, Stony Brook University, Stony Brook, NY 11794, USA
5
Biology Department, Woods Hole Oceanographic Institution, Woods Hole, MA, USA
Ornithogenic soils are “bird derived” soils developed over time by the occupation of bird species and subsequent deposition of their guano, tissues, and prey remains (Syroechkovsky 1959; Emsl
Data Loading...
