Taphonomy of two Holocene penguin taphocoenoses in Potter Peninsula, South Shetland Islands, Antarctica

ABSTRACT

Abandoned rookeries belonging to any of the Pygoscelis species are very particular taphocoenosis, usually preserved due to the accumulations of bones, pebbles, and guano year after year in the same nesting area, that condense together with other biogenic material and form ornithogenic sediments. The results of the excavation, sieved and analyses of sediment and materials found in two rookeries formed during the last 8000 years, named Pingfo I and Pingfo II and found in the 25 de Mayo/King George Island (South Shetland Islands, West Antarctica) are presented here. The analyses of the bones and eggshells, taxonomic and ontogenetic composition, elements representation, transport degree, predation, and scavenging marks, together with the micropalaeontological content provided informative tools for the reconstruction of the nesting areas, suggesting that bones were transported and accumulated in Pingfo I that would represent high energy beach, whereas a breeding colony was settled in Pingfo II. The preservation of hexactinellid spicules and several arthropod remains are particularly informative for the levels at Pingfo I. The preservation of a Culicidae (Diptera) wing could be the first middle Holocene record of the group in Antarctica, the only continent without extant mosquitoes.

Graphical Abstract

KEYWORDS:

• Breeding colonies
• sub-fossil bones
• Pygoscelis
• Spheniscidae
• Stranger point

Acknowledgments

The authors, solely responsible for the interpretations and contents expressed here, want to thank the IAA, FFAA, and all the personal of the Carlini Scientific Station for logistic and field support. To Luciano Segura, and Cecilia Amenabar for access to the specimens, and the following researchers for their help in the identification of different taxa: Renato García (lichens), Carolina Matula and Liliana Quartino (seaweeds), Evangelina Palópolo (sea urchins), and Maximiliano Garzón (mosquitos). CAH and JNG also thank Oceanwide Expeditions, Vlissingen (NL) and particularly to Ko de Korte for their support. We also thank to Leandro Pérez, Washington Jones, an anonymous reviewer, and the editor in charge for their valuable comments.

Disclosure statement

No potential conflict of interest was reported by the author(s).

Author contributions

MR, director of the project, organized the trip to make the fieldwork possible. CAH and JNG collected and processed the materials in the field. CAH and JNG conceived and designed the present study. BQ processed the sample in the laboratory and examined all the material under a binocular microscope. CAH and JNG wrote the manuscript and prepared the figures, BQ contributed to the preparation of the draft. CAH, JNG, BQ, and MR revised and approved the final version.

Supplementary material

Supplemental data for this article can be accessed online at https://doi.org/10.1080/08912963.2022.2132859

Additional information

Funding

The Instituto Antártico Argentino (Dirección Nacional del Antártico) funded the field works, Universidad Nacional de La Plata (PI N955 and PI N953), Agencia Nacional de Promoción Científica y Tecnológica (PICT 2016-0607), and Consejo Nacional de Investigaciones Científicas y Técnicas (PIP 0096) partially supported the research.