Naturwissenschaften

, Volume 96, Issue 5, pp 631–635

Contribution of anadromous fish to the diet of European catfish in a large river system

  • Jari Syväranta
  • Julien Cucherousset
  • Dorothée Kopp
  • Aurélia Martino
  • Régis Céréghino
  • Frédéric Santoul
Short Communication

DOI: 10.1007/s00114-009-0511-3

Cite this article as:
Syväranta, J., Cucherousset, J., Kopp, D. et al. Naturwissenschaften (2009) 96: 631. doi:10.1007/s00114-009-0511-3

Abstract

Many anadromous fish species, when migrating from the sea to spawn in fresh waters, can potentially be a valuable prey for larger predatory fish, thereby efficiently linking these two ecosystems. Here, we assess the contribution of anadromous fish to the diet of European catfish (Silurus glanis) in a large river system (Garonne, southwestern France) using stable isotope analysis and allis shad (Alosa alosa) as an example of anadromous fish. Allis shad caught in the Garonne had a very distinct marine δ13C value, over 8‰ higher after lipid extraction compared to the mean δ13C value of all other potential freshwater prey fish. The δ13C values of European catfish varied considerably between these two extremes and some individuals were clearly specializing on freshwater prey, whereas others specialized on anadromous fish. The mean contribution of anadromous fish to the entire European catfish population was estimated to be between 53% and 65%, depending on the fractionation factor used for δ13C.

Keywords

Alosa alosaAnadromous fishMigrationMixing modelSilurus glanisStable isotopes

Copyright information

© Springer-Verlag 2009

Authors and Affiliations

  • Jari Syväranta
    • 1
  • Julien Cucherousset
    • 2
  • Dorothée Kopp
    • 1
  • Aurélia Martino
    • 1
  • Régis Céréghino
    • 1
  • Frédéric Santoul
    • 1
  1. 1.EcoLab, UMR 5245 (CNRS-UPS-INPT)Université Paul SabatierToulouse Cedex 9France
  2. 2.Centre for Conservation Ecology and Environmental Change, School of Conservation SciencesBournemouth UniversityPooleUK