Isotope analysis of Pecho Coast sea otters thus far and next steps

Specimens were prepared at the University of Utah Archaeological Center and sent to Yale Analytical and Stable Isotope Center , where the Isotope Analysis Laboratory measured their Carbon and Nitrogen contents.

Isotopic Analysis of Pecho Coast’s Sea Otters: Thus Far and Next Steps Presenter Auriana Dunn BACKGROUND Enhydra lutris, the sea otter, is a keystone and endangered species of the Pacific Coast. This project analyzes ancient sea otter remains from the Pecho Coast archaeological site in Central California using isotopic analysis to study their diets. METHODS Literature Review: Previous isotopic studies on Pecho Coast otters were reviewed, allowing the new data to be incorporated into an expanded isotopic food web. Isotopic Analysis: Specimens were prepared at the University of Utah Archaeological Center and sent to Yale Analytical and Stable Isotope Center , where the Isotope Analysis Laboratory measured their Carbon and Nitrogen contents. C. lawi went extinct in the late Holocene epoch. Chendytes lawi (extinct flightless duck) The extinction of C. lawi created a niche for E. lutris to exploit. By understanding the historical diet of sea otters, ecologists can gain insights into how they have adapted since the late Holocene. Enhydra lutris (sea otter) DISCUSSION These initial literature review and isotope analysis steps set the foundation for the rest of this project. The next phase will involve comparing the expanded carbon and nitrogen data from the archaeological otters to contemporary sea otter isotope studies, including a comprehensive literature review on modern Enhydra lutris and statistical analysis of the data sets. Fig. 1: Stable isotope analysis (Jones et al., 2021) of the extinct flightless duck, sea otters, harbor seals, and Brandt’s cormorant, with nitrogen isotopes plotted against carbon isotopes. This project aims to expand the historical sea otter (E. lutris) food web. Auriana Dunn, Department of Anthropology, University of Utah Brian Codding, Department of Anthropology, University of Utah Daniel Dalmas, Department of Anthropology, University of Utah ACKNOWLEDGMENTS/CITATIONS Stable isotope measurements were performed at the Yale Analytical and Stable Isotope Center (YASIC), a Yale Institute for Biospheric Studies (YIBS) research center. Chendytes illustration by: Scott Reid Jones, T. L., Coltrain, J. B., Jacobs, D. K., Porcasi, J., Brewer, S. C., Buckner, J. C., ... & Codding, B. F. (2021). Causes and consequences of the late Holocene extinction of the marine flightless duck (Chendytes lawi) in the northeastern Pacific. Quaternary Science Reviews, 260, 106914.