oa Amino Acid-Specific Isotope Analysis in Snow Petrel Stomach Oil Deposits: Tracing Antarctic Sea Ice and Ecosystem Shifts

Reconstructing past Antarctic sea ice variability is challenging due to limited long-term records. This study applies compound-specific stable isotope analysis (CSIA) of amino acids in snow petrel stomach oil deposits from Dronning Maud Land, Antarctica, to distinguish environmental changes from dietary shifts over glacial-interglacial cycles. By analyzing d¹³C and d¹5N values in source and trophic amino acids, researchers track foraging habitats and trophic structure changes. Significant isotope shifts during deglaciation (∼17,000 years ago) reflect sea ice retreat, while lipid biomarkers and XRF data reveal polynya formation during the Last Glacial Maximum. These findings enhance our understanding of past sea ice dynamics and ecosystem responses to climate change.