Living and foraging at a climatic and coastal biogeographic transition zone: further observations on the mid-Holocene and the megamidden period of the west coast of South Africa
Keywords:coastal foraging, large shell middens, black mussels, limpets, Lamberts Bay, Climatic Optimum, settlement patterns, silcrete
We report on excavations at Deurspring, north of Lamberts Bay, South Africa. Earlier work there provided the first evidence of mid-Holocene occupation of the west coast of South Africa. This was unexpected, as previous research argued for an occupational hiatus in the local cultural sequence due to adverse climatic conditions and limited drinking water. Deurspring also provided further insights into the so-called megamidden period (3200–1900 cal BP), a time when people relied heavily on marine resources and accumulated very large shell middens through intense harvesting of predominantly black mussels. Our new work in the area shows that local fauna was procured during rather brief mid-Holocene visits, while groups moved over large areas from where they sourced exotic stone raw materials. Deurspring sites are much smaller than megamiddens, but their occupation intensifies after 3200 cal BP, and quantities of lithic artefacts indicate a domestic signature. Black mussels were harvested in greater numbers over time but their quantities were limited by the northward biogeographic trend of increasing abundance of intertidal limpets at the expense of black mussels, as observed today. This factor likely limited the intense exploitation of black mussels around Deurspring and probably explains why large-sized megamiddens never formed there.