Effects of lipid removal and preservatives on carbon and nitrogen stable isotope ratios of squid tissues: Implications for ecological studies

► We examine the effect of preservatives on δ13C and δ15N from squid muscle and beak. ► Lipid removal, DMSO, formalin and ethanol affected δ13C and δ15N on squid muscle. ► Lipid removal in muscle reduces the effect of preservation, except for formalin. ► Squid beaks preserved in formalin and ethanol can be used for stable isotope analysis.