Lipid Correction for Carbon Stable Isotope Analysis of Deep-Sea Fishes

Authors

Joel C. Hoffman, United States Environmental Protection Agency
Tracey Sutton, Virginia Institute of Marine ScienceFollow

ORCID

0000-0002-5280-7071

Document Type

Article

Publication Title

Deep Sea Research Part I: Oceanographic Research Papers

ISSN

0967-0637

Publication Date

8-2010

Keywords

δ13C, δ15N, Muscle tissue, Normalization, Mass balance

Abstract

Stable isotope analysis of fish tissue can aid studies of deep-sea food webs because sampling difficulties severely limit sample sizes of fish for traditional diet studies. The carbon stable isotope ratio (δ¹³C) is widely used in food web studies, but it must be corrected to remove variability associated with varying lipid content in the tissue. A lipid correction has not been determined for any deep-sea fish. These fishes are ideal for studying lipid correction because lipid content varies widely among species. Our objective was to evaluate an application of a mass balance δ¹³C correction to a taxonomically diverse group of deep-sea fishes by determining the effect of lipid extraction on the stable isotope ratios, examining the quality of the model parameters derived for the mass balance correction, and comparing the correction to published results. We measured the lipid extraction effect on the nitrogen stable isotope ratio (δ¹⁵N) and δ¹³C of muscle tissue from 30 North Atlantic species. Lipid extraction significantly increased tissue δ¹⁵N (+0.66‰) and δ¹³C values, but the treatment effect on δ¹³C was dependent on C:N, a proxy for lipid content. We compared the lipid-extracted δ¹³C to the δ¹³C predicted by the mass balance correction using model variables estimated from either all individuals (pooled) or species-by-species or using published values from other species. The correction using the species-by-species approach performed best; however, all three approaches produced corrected values that were generally within 0.5‰ of the measured lipid-free δ¹³C and that had a small over-all bias (<0.5‰). We conclude that a generalized mass balance correction works well for correcting δ¹³C in deep-sea fishes, is similar to that developed for other fishes, and recommend caution when applying a generalized correction to fish with high lipid content (C:N >8).

DOI

10.1016/j.dsr.2010.05.003

Volume

57

Issue

8

First Page

956

Last Page

964

Comments

Published by Elsevier Ltd.

Additional Comments

Natural Environment Research Council grant #: NE/C512961/1; NSF grant #: OCE 0853761

NSUWorks Citation

Joel C. Hoffman and Tracey Sutton. 2010. Lipid Correction for Carbon Stable Isotope Analysis of Deep-Sea Fishes .Deep Sea Research Part I: Oceanographic Research Papers , (8) : 956 -964. https://nsuworks.nova.edu/occ_facarticles/525.