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Hydrobiologia

, Volume 822, Issue 1, pp 173–188 | Cite as

Feeding habits of the swordfish (Xiphias gladius Linnaeus, 1758) in the subtropical northeast Pacific

  • Ariana Trujillo-Olvera
  • Sofía Ortega-García
  • Arturo Tripp-Valdez
  • Ofelia Escobar-Sánchez
  • Tatiana A. Acosta-Pachón
Primary Research Paper

Abstract

With the aim to expand the understanding of the feeding ecology of the swordfish, two supplementary techniques were used: analysis of stomach contents, including 244 samples; and analysis of stable carbon (δ13C) and nitrogen (δ15N) isotopes, with 128 samples of muscle tissues from animals collected in the western coast of Baja California. Samples were obtained from swordfish captured by the longline fleet that operates along the western coast of Baja California peninsula. Thirty-three different prey types were identified through the analysis of stomach contents. Based on the index of relative importance (IRI), cephalopods accounted for 98.91%, fish 0.88%, and pelagic crustaceans 0.21%. The stable isotope analysis showed δ15N values between 13.05‰ and 19.66‰, and δ13C values between − 19.32‰ and − 15.60‰, indicating that the swordfish feeds primarily on oceanic species. The stable isotope mixing model (SIAR) established that prey species that most contribute to the diet of Xiphias gladius were cephalopods, followed by the crustacean Pleuroncodes planipes, and the fish Lagocephalus lagocephalus. The SIBER test corroborates similar diets between sexes and sex-maturity groups, indicating that all swordfish analyzed essentially occupied the same trophic niche.

Keywords

Feeding ecology Stable isotopes Stomach content analysis Swordfish δ15δ13

Notes

Acknowledgements

This study was developed in the projects: SIP20141071- SIP20150861 supported by Instituto Politécnico Nacional, and the project, “From the Bay to the Banks: understanding food web links between Magdalena Bay and the offshore pelagic fish community,” in collaboration with the Rutgers University and supported by the Billfish foundation (SIP2012/19). We owe our gratitude to the staff of the Fish Ecology and Marine Chemistry Laboratories at the Centro Interdisciplinario de Ciencias Marinas (CICIMAR), where our samples were analyzed. The corresponding author is a scholar of EDI and COFAA, IPN. We offer our special thanks to Carolina Minte, Marlon H. Roman Verdesoto, and María Elena Sánchez-Salazar, who contributed to the English edition of the manuscript. Our thanks go to the anonymous reviewers for their constructive comments on an earlier version of this manuscript that helped improve it.

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© Springer International Publishing AG, part of Springer Nature 2018

Authors and Affiliations

  1. 1.Instituto Politécnico Nacional-Centro Interdisciplinario de Ciencias MarinasLa PazMexico
  2. 2.CONACYT-Dirección de Cátedras CONACYTCiudad De MéxicoMexico
  3. 3.Universidad Autónoma de Sinaloa-FACIMARMazatlánMexico

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