Abstract
- A comparison of high-resolution δ18O values in the aragonite shells of Rangia cuneata with sub-monthly δ18Owater, temperature, and salinity data reveals extended and unpredictable periods of growth cessation from late fall to early spring. We hypothesize that fluctuations in temperature and salinity cause this growth cessation. We utilized δ13Cshell, δ13CDIC, and tissue δ13C values to estimate the amount of metabolic carbon incorporated into the shell carbonate in R. cuneata as a proxy for metabolic rate. Increases in the average amount of metabolic carbon incorporated into the shell carbonate increased with the average salinity along the Neuse River Estuary in North Carolina, USA, suggesting that variations in salinity lead to stress, despite the species' wide salinity tolerance. Alternative species are preferable for paleoclimate reconstructions until the triggers of growth cessation in this species are identified.