Return to the Shellfish Beds: New Insights on Use of California Sea Mussels (Mytilus californianus) and Turban Snails (Tegula spp.) Based on Harvesting Experiments

ABSTRACT Sea mussels and turban snails are among the most abundant mollusks recovered from central California middens. Experimental harvests of these and other shellfish have been conducted to help interpret archaeological findings, but methodological complications have plagued many of the early experiments. Here we report results of harvest experiments of mussels and turban snails completed between 2016 and 2022 on the Pecho coast of San Luis Obispo County. We developed a local formula to convert umbo thickness measurements into whole mussel valve length, and this article reports new return rates, including one of over 1,500 kcal/hour for mussels obtained by an experienced shellfish collector. This rate demonstrates the importance of accumulated knowledge in subsistence experiments, and suggests that mussels have higher dietary potential than previously thought. Archaeological mussel size profiles suggest that a selective (plucking-like) strategy was associated with sustainable harvest for at least the last 5,000 years on the Pecho coast.