Abandonment of Penguin Subcolonies in the Late Nineteenth Century on Inexpressible Island, Antarctica

Abstract

The impact of climate and weather on penguin ecology has attracted much research attention. To reconstruct the history of the penguin population, penguin carcasses on the surface and three ornithogenic sediment profiles were collected in a ditch area beneath abandoned penguin subcolonies on a high terrace to the northwest of the modern colony in Seaview Bay, on Inexpressible Island, East Antarctica. A rapid increase in penguin-derived element contents in the sediment profiles at~1700 Common Era (CE) indicates an increase in the penguin population of research area at the end of the Little Ice Age. However, surficial carcasses, geochemical characteristics of the sediment profiles, and field evidence indicate the subsequent abandonment of these penguin subcolonies. A period of intensified streamflow activity resulting from meltwater is a possible explanation for the colony abandonment. The dating results of the carcasses and sediment profiles constrain this event to around the late nineteenth century. The meltwater streams can be attributed to the interaction between enhanced moist air mass transport to the coastline of Victoria Land, rising temperatures, and the sloping topography. Comparisons with other regional records suggest that this type of event is common across East Antarctica and has significant impacts on penguin ecology.

Reconstructing Long-Term Changes in Avian Populations Using Lake Sediments: Opening a Window Onto the Past

“…By comparing this grouping to previously published chemical analyses of penguin droppings, the authors confirmed that the group of bio-elements is representative of the species of interest, and so could be used to understand changes in penguin numbers back in time. R-cluster analysis, which has been used worldwide, is often considered the most effective tool to identify ornithogenic elements if a nearby reference site (i.e., a nearby lake without avian inputs) is not available to distinguish the natural, background element concentrations (Zale, 1994;Sun et al, 2000Sun et al, , 2004Liu et al, 2005Liu et al, , 2006cHuang et al, 2009aHuang et al, , 2011Xu et al, 2011Xu et al, , 2016Xu et al, , 2019Xu et al, , 2020Roberts et al, 2017).…”

Emerging biological archives can reveal ecological and climatic change in Antarctica

“…Primary productivity/surface productivity (Berg, Melles, et al, 2019 ; Emslie, 2021 ; Xu et al, 2020 )…”

“…Analyses of dietary and/or stable isotope composition of animal remains reflects the environment in which the animals were feeding (e.g., in polynyas versus loose pack ice), which sheds light on sea ice conditions, and more broadly, can inform us of species responses to environmental change (Berg, White, Hermichen, et al, 2019 ; McClymont et al, 2022 ) (Tables 1 and 2 ). Several studies indicate that episodic occupation of sites by Adélie penguins on the Antarctic continent (e.g., Xu et al, 2020 ) reflects periods of enhanced marine productivity and greater nesting site availability during past warmer climates, in particular the penguin ‘optimum’ (~2–5 million years ago, Ma) (see Younger et al ( 2016 ) and references within). Seal hairs (Hodgson & Johnston, 1997 ) and changes in the deposition of bio‐elements from penguin guano (Sun et al, 2000 ) can be used as proxies for population size; the latter study finding a peak in population size corresponding to a time of high precipitation (~1.4–1.8 ka), suggesting a climatic influence.…”

“…(Aymerich et al, 2016;Saunders et al, 2018) have been used to determine inputs of minerals related to catchment dynamics, such as evidence of glacier fluctuations(Berg, White, Jivcov, et al, 2019), impact of volcanism on past penguin populations via signatures of guano and guano-related elements(Roberts et al, 2017), and changes in Southern Hemisphere westerly wind strength(Perren et al, 2020; Pygoscelis adeliae (Adelie penguin)(Xu et al, 2020), Aptenodytes forsteri (Emperor penguin)(Huang et al, 2016), seals(Huang et al, 2011) Pagodroma nivea (snow petrel) TA B L E 2Note: See Supplementary information 1 for additional examples.…”