Multi-isotope evidence for cattle droving at Roman Worcester

Tooth enamel from six cattle mandibles excavated from Roman deposits at The Hive development site, Worcester (mid-2nd to early 4th century AD) was subjected to strontium, oxygen and carbon isotope analyses (87Sr/86Sr, δ18O and δ13C) to investigate the movement of cattle into Worcester, a purported regional cattle market, during the Roman period. Strontium isotope ratios show that none of the cattle were born and bred in close proximity to Worcester and arrived as mature beasts some time before death. Whilst two are consistent with origins in the region of Old Red Sandstone of Herefordshire to the west, the unusually high strontium isotope ratios of four of the cattle (i.e. >0.714) show that they originated in a region of ancient or radiogenic rocks such as granites which are found only in the west and north of Britain (e.g. Wales, the Lake District and northern Scotland) based on the currently available biosphere data. Comparison of the oxygen and carbon isotope values also suggests that the cattle were not from the same herd, but interpretation is complicated by the lack of comparative cattle data for the Roman period as well as other time periods. The severe wear of the molars from the aged cattle in this study also limits the interpretation of the results. More isotopic analyses are needed from other British sites in order to fully understand the implications of cattle movement into urban centres during the Roman period.