Paleoindian Use of Shellfish on California's Northern Channel Islands

California’s Northern Channel Islands have produced some of the earliest evidence for seafaring, maritime adaptations, and aquatic resource use in the Americas. Here, I summarize what is known about patterns of Paleoindian shellfish use at ten Paleocoastal sites on San Miguel and Santa Rosa islands dated between about 12,200 and 11,000 calendar years before present (cal BP). These Terminal Pleistocene sites have produced shellfish remains that are mostly dominated by cool water and rocky shore taxa (i.e., red abalone, California mussel) harvested from rocky intertidal habitats. One site on eastern Santa Rosa Island has produced the remains of estuarine clams dated to ~11,100 cal BP, however, representing some of the earliest direct evidence for human exploitation of estuarine habitats in North America. The earlier assemblages also appear to be dominated by cold water species probably associated with a Younger Dryas cooling of sea surface temperatures in the northeastern Pacific. When considered as a whole, these Channel Island shellfish assemblages suggest that Paleoindian peoples regularly harvested a variety of shellfish from nearshore habitats on the Northern Channel Islands. Many of these sites are also associated with the remains of aquatic vertebrates and sophisticated hunting equipment that indicate a broad-based maritime economy that was probably supplemented significantly with terrestrial plant foods, especially carbohydrate-rich geophytes.