Marine and Freshwater Research Marine and Freshwater Research Society
Advances in the aquatic sciences
REVIEW

Stable isotope analysis as a tool for elasmobranch conservation research: a primer for non-specialists

D. S. Shiffman A B F , A. J. Gallagher A B , M. D. Boyle C , C. M. Hammerschlag-Peyer D and N. Hammerschlag A B E

A Leonard and Jayne Abess Center for Ecosystem Science and Policy, University of Miami, PO Box 248202, Coral Gables, FL 33 124, USA.

B RJ Dunlap Marine Conservation Program, University of Miami, 4600 Rickenbacker Causeway, Miami, FL 33 149, USA.

C Pacific Shark Research Center, Moss Landing Marine Laboratories, 8272 Moss Landing Road, Moss Landing, CA 95 039, USA.

D Florida International University, 3000 NE 151st Street, North Miami, FL 33 181, USA.

E Rosenstiel School of Marine and Atmospheric Sciences, 4600 Rickenbacker Causeway, Miami, FL 33 149, USA.

F Corresponding author. Email: David.Shiffman@gmail.com

Marine and Freshwater Research 63(7) 635-643 http://dx.doi.org/10.1071/MF11235
Submitted: 24 October 2011  Accepted: 30 April 2012   Published: 2 July 2012

Abstract

Many elasmobranch species are undergoing population declines on a global scale; however, implementation of effective conservation and management strategies is hindered, to a large extent, by a lack of sufficient data on diet, life history and behaviour. This work is a primer of how stable isotope analysis can be used as a cost-effective, relatively simple tool for examining resource use patterns (e.g. diet, habitat) and generating relevant data in support of science-based elasmobranch conservation and management. Specifically, isotopes can resolve the feeding niches of elasmobranchs, detect ontogenetic trophic shifts and calculate relative diet breadth of different species. Stable isotope analysis can also be employed to investigate the extent of anthropogenic impacts on diet or to infer the source of toxins affecting elasmobranchs. Additionally, this tool can be used to study migration patterns and habitat usage. Depending on the tissue analysed, this technique can also be non-lethal and minimally invasive. The limitations of stable isotope analysis are discussed, and recommendations for future work are presented.

Additional keywords: dietary analysis, ecotoxicology, food web analysis, individual diet specialisation, migration.


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