Red Abalone (Haliotis rufescens) "Middens" (Features) on the Central California Coast

So-called "red abalone middens" are long-recognized, highly researched archaeological deposits commonly associated with the Northern Channel Islands. To contribute to ongoing dialogue about the causes underlying the presence/absence of these shell features, here we attempt to define the spatial and temporal distribution of red abalone shells by summarizing 554 radiocarbon dates from 211 sites on the Channel Islands and central coast. Dates show red abalone exploitation as early as 12,500 cal BP1 on the islands with dense concentrations after 8,500 cal BP. On the mainland, red abalone shells date as early as 9,960 cal BP, but dense shell features post-date 6,500 cal BP. Between 6,500 and 4,500 cal BP, red abalone were relatively abundant across the mainland and islands. Changes in sea surface temperatures driven by the California Current seem to explain Q3 some of the temporal variation in the presence/absence of this mollusk. The so-called "red abalone middens" are long-recognized and well-researched archaeological deposits, commonly associated with with the Northern Channel Islands. To contribute to the ongoing dialogue on the underlying causes of the presence/absence of these shell features, here we attempt to define the spatial and temporal distribution of red abalone shells by summarizing 554 radiocarbon dates from 211 sites. in the Channel Islands and central coast. Dates show exploitation of red abalone as early as 12,500 cal BP1 on the islands with dense concentrations after 8,500 cal BP. On the mainland, red abalone shells date to 9,960 cal BP, but the dense features of the shells are later than 6,500 cal BP. Between 6,500 and 4,500 cal BP, red abalone were relatively abundant across the mainland and islands. Changes in sea surface temperatures driven by the California Current appear to account for part of the temporal variation in the presence of red abalone. /absence of this mollusk.