The Effect of Postdepositional Fragmentation on Archaeological Oyster Shell Metrics

Summary

This is an abstract from the "SAA 2025: Individual Abstracts" session, at the 90th annual meeting of the Society for American Archaeology.

The eastern oyster (Crassostrea virginica) is an ecological and cultural keystone species that has been exploited by humans for millennia. Oyster size is a good proxy for population health, and researchers frequently use valve height and length measurements from archaeological and paleontological contexts that provide baselines for assessing past human impacts and have potential to inform present-day management.

Fragmentation, however, is rarely assessed in archaeological studies of oyster size. We determine the effects of fragmentation on oyster size through study of bulk samples from stratified contexts at two Florida Gulf coast sites, Garden Patch (8DI4) and Calusa Island (8LL45). Both collections are composed of whole oyster valves, valve fragments with hinges, and valve fragments lacking hinges. Comparisons of whole valve survival rates, mean fragment size, and whole valve height and length show correlations well described by nonlinear regression models. These results suggest variation in valve height and length are explained by taphonomic processes, not differences in the pre-fragmented oyster population, which complicates current approaches to the use of archaeological oyster assemblages as a proxy for past oyster reef health. We encourage continued critical evaluation of the archaeology of oyster assemblages and interrogation of their historical ecological implications in the present.

This Resource is Part of the Following Collections

• Society for American Archaeology 90th Annual Meeting, Denver, CO (2025)   •
• SAA 2025: Individual Abstracts

Keywords

Record Identifiers

Abstract Id(s): 52878