Easter Island Subsistence

by

Williams S. AYRES

I. Marine Subsistence Problems

Dietary quantification for prehistoric populations has concerned archaeologists because of the central role subsistence methods play in the life patterns of hunting and gathering or agricultural peoples. Archaeological attempts to determine subsistence bases for horticultur- alists, especially quantitatively, have been less successful than those for hunters and gatherers because of domesticated plant preservation problems ; however, differential preservation of food remains is being recognized as creating a significant bias in hunter-gatherer subsistence reconstructions as well. In the case of agriculturalists, calculations of arable land productivity within specified areas, e.g., site catchments or valley systems, offer one method for establishing subsistence and population parameters. Land productivity calculations have been used in estimating population size in Polynesia (cf. Bellwood 1972, Kirch and Kelly 1975).

Although this study deals with a horticul- turally-based population, it emphasizes marine resources as essential components of the larger subsistence mix or pattern. Given the well-established importance of marine foods due to the limited land fauna in the Pacific, detailed information on maritime adaptation seems overdue. Characterizing the cultural

adaptations made by Pacific Islanders in relative isolation to environments that are marginal in food resources requires quantified cultural ecological studies covering long time periods.

Understanding Easter Island culture and its relationships to other Polynesian cultures, and perhaps as some suggest, to South American aboriginal cultures, is difficult because no established sequence of portable artifacts reflecting culture change or stability is yet available. This is especially true for the early stages of Easter Island prehistory. Artif actual evidence regarding the degree of the island's isolation prior to European contact is limited ; the degree of isolation determines the extent to which the cultural developments on Easter Island are the result of an independent adaptive process. The field research on which this paper is based sought data regarding subsistence and technological stability as one facet of the larger culture change problem.

In the Easter Island case, as in most detailed subsistence analyses, the available ethnographic data is inadequate for quantifying even the main food resources and archaeological studies provide the only means to derive such statements. Easter Island presents a good opportunity to resolve questions about both plant and animal dietary components because the arable land area as well as the diversity of hunted and gathered foods are limited and