Effects of blood anticoagulants on stable isotope values of sea turtle blood tissue
Stable isotope analysis of blood tissue has answered many questions about sea turtle ecology. Because reptile blood rapidly coagulates (in less than one minute), studies collecting this tissue in the field must make use of anticoagulants to preserve samples for analysis back at the lab. However, although anticoagulants are commonly used in sea turtle studies, their effects on blood stable carbon and nitrogen isotope ratios are unknown. Here we examined the effects of the most common anticoagulants on stable isotope ratios in blood of the green sea turtle Chelonia mydas. We found that sodium heparin had the least effect on stable carbon and nitrogen ratios and we thus recommend its use for all future isotopic studies of sea turtle blood.