Of missions and marshes: Stable isotope analysis of Mission-Era Guale oyster harvesting on St. Catherines Island, Georgia

Abstract

This article presents the results of oxygen stable isotope analysis on eastern oyster (Crassostrea virginica) samples (n = 25) from a Mission-Era (ca. AD 1565–1680) site, Pueblo Santa Catalina de Guale, on St. Catherines Island, GA. Stable isotope analysis was used to assess the seasonality of oyster harvesting on St. Catherines Island during the Mission Era to better understand how Spanish colonization and the Catholic mission system may have impacted Guale foodways. Five eastern oyster left valves were sampled from each known neighborhood of Pueblo Santa Catalina de Guale. Existing data regarding the seasonality of pre-colonial mollusk collection on St. Catherines Island and elsewhere in the coastal Southeast are discussed in conversation with the results of this analysis. This work indicates that Guale residents of St. Catherines Island during the Mission Era were harvesting oysters most intensely during cooler months. This pattern is consistent with estimates of pre-colonial shellfishing seasonality across the region and may even represent a modest increase in the seasonal constriction of shellfishing when compared to data from the preceding period. Salinity estimates based on the isotope data also suggest Guale people during the Mission Era were collecting from a comparatively narrower range of estuarine habitats. We argue that these subtle shifts are a consequence of the reorganization of Guale labor associated with missionization.

Keywords:

• Bivalve geochemistry
• indigenous foodways
• colonization
• Southeastern North America

Supplemental Files

Supplemental Figure 1: Map of Pueblo Santa Catalina de Guale showing the mission compound surrounded by the pueblo neighborhoods (Blair 2015:77)

Supplemental Figure 2: (Top)Diagram of a left oyster valve showing relevant structures and anatomical directions, Redrafted from Kent 1992:10, figure 2, and (Bottom) Diagram of an eastern oyster (Crassostrea virginica) thick section showing light and dark growth bands. Redrafted from Andrus 2012:126, figure 6.3.

Acknowledgements

Excavations on St. Catherines Island were made possible by the Edward John Noble Foundation, the St. Catherines Island Foundation, the American Museum of Natural History, and the University of Alabama Department of Anthropology. Previously excavated shell midden samples were loaned to the University of Alabama by Anna Semon and David Hurst Thomas at the American Museum of Natural History. The facilities, equipment, and training required for this project were supplied by the Alabama Stable Isotope Laboratory. Funding for some of the Alabama Stable Isotope Lab instrumentation used in this project came from National Science Foundation Instruments and Facilities grant EAR-0949303. Christine Bassett provided crucial instruction on collecting stable isotope samples and Joe Lambert oversaw the processing of the calcite samples at the Alabama Stable Isotopes Laboratory.

Disclosure statement

No potential conflict of interest was reported by the authors.

Data availability statement

Tables containing the data discussed in this article can be found in the MA thesis entitled “Examining Change, Persistence, and Variation in the Role of Invertebrate Fauna in Mission-Era Guale Foodways on St. Catherines Island, GA” which is available through the University of Alabama Institutional Repository.

Additional information

Funding

Funding to conduct oxygen stable isotope analysis was provided by the Society for Georgia Archaeology in the form of the Graduate Student Research Grant. Additional financial support for this project came from the University of Alabama David and Elizabeth DeJarnette Endowed Scholarship fund.