Ethanol preservation effects on stable carbon, nitrogen and hydrogen isotopes in the freshwater pearl mussel

Abstract Chemical preservatives can alter stable isotope ratios in animal tissues. The effects of preservation on δ 13 C and 15 N values have been investigated a variety species, but not 2 H or the freshwater pearl mussel (FPM, Margaritifera margaritifera ) We evaluated effect ethanol (unpreserved vs preserved tissues) over 6 months C, FPM foot gonad Ethanol significantly increased (foot 0.4 ‰; 0.3 ‰), whereas it did affect 0.2 − 0.1 ‰). positive 7.1 14.5 ‰) negative C:N 0.1; 0.5) depended tissue type, with larger found lipid-rich gonad. Overall, affected more than After 1 month preservation, remained rather stable, significant changes were only observed values. results imply that ethanol-preserved samples be used if potential shifts isotopic elemental are accounted for prior running mixing models estimating dietary proportions.