Flexibility in the Foraging Strategies of the Galapagos Sea Lion Inferred from a Multiple Approach Analysis

  • Diego Páez-Rosas
  • Marjorie Riofrío-Lazo
  • David Aurioles-Gamboa
Chapter
Part of the Social and Ecological Interactions in the Galapagos Islands book series (SESGI)

Abstract

Studies concerning the foraging behavior of the endangered Galapagos sea lion (Zalophus wollebaeki) are essential to understand long-term conservation challenges and predict population fluctuations. This study provides a comparative analysis of variables related to the foraging habits and trophic niche flexibility of Z. wollebaeki. Complementary stable isotopes and remote sensors were used to measure space-time variables concerning Z. wollebaeki foraging habits among populations in the Galapagos Archipelago. In spatial terms, isotopic values (n = 321) showed differences regarding foraging grounds (δ13C: p = 0.015). These results also show test subjects maintained equilibrium in the trophic level of their diet (δ15N: p = 0.152). The results of this study confirm the evolutionary behavior of Z. wollebaeki has resulted in a high level of flexibility in foraging habits. This adaptability affords a higher advantage for survival in the Galapagos: a confined ecosystem with limited resources.

Notes

Acknowledgements

We acknowledge the financial support received from the Prometeo Project of Secretaría Nacional de Ciencia, Tecnología e Innovación (Ecuador); the Consejo Nacional de Ciencia y Tecnología (CONACyT); and the Instituto Politécnico Nacional of México and logistical support of Project SIP-20120061. Thanks to the Parque Nacional Galápagos (PNG) for the research permits and for help provided during the sampling logistic.

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Copyright information

© Springer Science+Business Media New York 2014

Authors and Affiliations

  • Diego Páez-Rosas
    • 1
    • 2
    • 3
  • Marjorie Riofrío-Lazo
    • 4
    • 5
  • David Aurioles-Gamboa
    • 6
  1. 1.Galapagos Science Center, Universidad San Francisco de Quito (USFQ) and The University of North Carolina at Chapel HillIslas GalápagosEcuador
  2. 2.Programa PROMETEO-SENESCYT, Secretaria Nacional de Educación Superior, Ciencia, Tecnología e Innovación del EcuadorQuitoEcuador
  3. 3.Parque Nacional Galápagos, Unidad Técnica San CristóbalIslas GalápagosEcuador
  4. 4.Galapagos Science Center, Universidad San Francisco de Quito (USFQ)San Cristóbal IslandEcuador
  5. 5.Galapagos Science Center, The University of North Carolina at Chapel Hill (UNC)San Cristóbal IslandEcuador
  6. 6.Laboratorio de Ecología de Pinnípedos “Burney J. Le Boeuf”Centro Interdisciplinario de Ciencias Marinas, Instituto Politécnico NacionalLa PazMéxico

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