Radiocarbon dates (SUERC - Centre for the Isotope Sciences, University of Glasgow, Glasgow, U.K; University of California-Irvine, California, U.S.A) from a snow petrel stomach-oil deposit, 1401MUM1, from the Theron Mountains (-79.049, -28.329), eastern Weddell Sea region. 1401MUM1 was collected as part of a NERC-funded expedition (2015) from the Theron Mountains, a mountain range in Coats Land. Radiocarbon ages were calibrated to calendar ages using MARINE20 (Heaton et al. 2020; doi:10.1017/RDC.2020.68) using Holocene deltaR of 670 ± 50 yr (Björck et al. 1991).