Radiocarbon Dating of Prehistoric Shell from New Zealand and Calculation of the δr Value Using Fish Otoliths

We calculated a new ∆R for New Zealand waters using 14 C dates of historic shell previously presented by McFadgen and Manning (1990), and fish otoliths dated by Kalish (1993). We obtained a new estimate of −25 ± 15 14 C yr. To test the accuracy of this value for correcting conventional 14 C marine ages, we dated shell of a variety of different species excavated at the prehistoric site of Shag Mouth, North Otago. We compared the results with a pooled mean date for terrestrial samples and calculated a local ∆R value that we found statistically indistinguishable from the new ∆R estimate for New Zealand.