Phosphate as an indicator of occupational intensity at shell midden sites on the central coast of British Columbia

We use reagent colorimetry to measure phosphate concentrations in fine-fraction matrix from shell midden sites on the central coast of British Columbia, Canada. The results show strong correlations with fish bone densities (that is, number of identified specimens per litre of fine fraction matrix) and site area, which have been used previously to infer the intensity of site occupation in the region. Despite a long history of use in shell midden …