Staple, Feasting, or Fallback Food? Mussel Harvesting Among Hunter-Gatherers in Interior Central California

Abstract

Shells are a visible component of archaeological middens in Central California. While coastal and bay shore sites are often dominated by shells, these food items were sometimes hauled many kilometers from their collection points and are found in appreciable numbers in inland sites as well. Using oxygen and carbon stable isotope data from 44 Mytilus sp. (mussel) shells, we reconstruct shellfish seasonality harvesting at one inland site dating to the Middle Period (ca. 2500-1000 cal yrs BP), CA-SOL-364. Data show that shells were collected from nearby Suisun Marsh and were harvested almost exclusively during winter, a pattern that contrasts with coastal and bay shore sites. Such a harvesting signature is unlike that expected for a food staple or a feasting resource. We suggest mussels were harvested as a fallback food, as a source of protein or micronutrient to complement carbohydrate-rich foods that were stored and consumed during winter, or perhaps were only exploited as opportunity costs relaxed during winter, making sessile mussels an attractive subsistence pursuit.

Compilation of a database of Holocene nearshore marine mollusk shell geochemistry from the California Current System

“…The methodology for age control on individual shells varied among studies; some provide age ranges defined by radiocarbon dating of material that was co-collected with shells from stratigraphic sections of the midden, some studies provide radiocarbon dates from individual shells, and some shells in the database were collected live. Eleven papers reported age ranges: Burchell et al (2013c), Eerkens et al (2005Eerkens et al ( , 2013Eerkens et al ( , 2016, Glassow et al (1994Glassow et al ( , 2012, Hallman et al ( 2013), Jazwa and Kennett (2016), Jones and Kennett (1999), Rick et al (2006a), and Robbins and Rick (2006). In cases when age was reported as a range, the range is listed in the database (age_range column) and the midpoint of the range is recorded as the age of shell (age_ybp).…”

An introduction to assessments

“…Bivalves and other intertidal resources have, for the most part, been considered an insignificant, or 'fall back' resource at coastal sites, especially when compared to other food sources such as fish or marine and terrestrial mammals (Eerkens et al 2016;Erlandson 2001). In previous archaeological studies, the presence of bivalves has often been little more than acknowledged (Fitzhugh 1995); however, as new methods emerge for studying the season and intensity of gathering, archaeologists are becoming better able to understand the role of bivalves in coastal economies of the past, especially regarding seasonal patterns of resource acquisition and by proxy, site occupation.…”