Testing the efficacy and reliability of common zooarchaeological sampling strategies: a case study from the Caribbean

Zooarchaeological analysis typically involves implementing a suitable sampling strategy that provides meaningful information representative of a site under investigation. To test the efficacy of how various sampling procedures can influence interpretation of a faunal assemblage, we analyzed in full, a large assemblage of mollusks (minimum number of individuals [MNI] = 58,000+) from the late Ceramic Age (ca. AD 850-1440) site of Coconut Walk on the island of Nevis (northern Lesser Antilles, Caribbean). These remains were recovered from 25 discrete 1 × 1 m units within a larger 5 × 5 m trench that overlaid a dense midden deposit. Using statistical procedures, we compared the results of the number of identified specimens (NISP), MNI, and weight (g) of each mollusk taxon between both units and plana to determine how different sampling strategies would have affected the interpretation of mollusk composition across space and time had different sampling procedures been used. The results reveal that sampling less than 16% (4 out of 25 squares for this study) of a midden is likely to produce results outside of a 95% confidence interval for the population composition, with samples of connected squares having a higher likelihood to lie outside the interval. Discerning change between plana (or layers) may require a larger sample (i.e., 16%+). In addition, samples selected randomly or judgmentally will produce similar results, provided that proper spacing is given between units. The data in this case suggest that the midden was efficiently sampled for midden composition and key species at a rate of 16% of the surface area.