Journal of California and Great Basin Anthropology

Point Bennett, on western San Miguel Island, California, was an important location for sea mammal hunting through time. We use stable oxygen isotopic (δ18O) measurements from California mussel (Mytilus californianus) shells to reconstruct a seasonal pattern of mussel harvesting by the human occupants of Point Bennett during three time intervals dated to the middle (~7,550 – 3,600 cal B.P.; CA-SMI-528, Stratum 3) and late (after ~3,600 cal B.P.; CA‑SMI-528, Stratum 1; CASMI-602) Holocene. During both periods of occupation at CA-SMI-528, mussel harvesting was primarily during the spring, coincident with onshore sea mammal breeding. This suggests a seasonal pattern of site occupation. At CA-SMI-602, mussel harvesting primarily occurred during the summer and fall. This is opposite when sea mammals are present in highest densities, suggesting year-round occupation. This shows how seasonality of mussel harvesting can be used alongside other indicators like seasonal availability of sea mammals to understand broader patterns of human mobility.