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bioRxiv · 10.64898/2025.12.12.693874

Dynamic emperor penguin colonies

Fretwell, P. T.·Jamieson, S. R.·MacDonald, G. J.
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Abstract

Here we report on the discovery of five emperor penguin breeding locations in West Antarctica, all of which have moved significant distances over the last decade. Three of the colonies could be considered previously undiscovered, while the other two are likely to be relocations due to ice shelf calving events. One of the sites, on the northwest tip of the Stancomb-Wills Ice Tongue has formed or significantly increased in size since 2022, possibly due to immigration from one or both of the two nearest colonies at Halley Bay and Stancomb-Wills colonies. Another colony near Case Island in the Bellinghausen Sea that has recently form is likely due to emigration from other colonies in the region that have suffered recent breeding failures due to early fast ice loss. We discuss the movement of these colonies and the implications for the wider metapopulation and our understanding of emperor penguins colony dispersal.

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Fretwell, P. T., Jamieson, S. R., MacDonald, G. J.. 2025-12-12. Dynamic emperor penguin colonies. https://doi.org/10.64898/2025.12.12.693874

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