Genetic introgression on freshwater fish populations caused by restocking programmes

  • María José Madeira
  • Benjamín J. Gómez-Moliner
  • Annie Machordom Barbe


The brown trout (Salmo trutta L.) is one of the best studied native salmonids of Europe. Genetic studies on this species suggest that a large proportion of the evolutionary diversity corresponds to southern European countries, including the Iberian Peninsula, where this study is focused. Stocking activities employing non-indigenous hatchery specimens together with the destruction and fragmentation of natural habitats are major factors causing a decrease of native brown trout populations, mostly in the Mediterranean basins of the Iberian Peninsula. The main aim of the present work is to examine the genetic structure of the brown trout populations of the East Cantabrian region, studying the consequences of the restocking activities with foreign hatchery brown trout specimens into the wild trout populations. We have based our study on the Polymerase Chain Reaction and Restriction Fragment Length Polymorphism technique conducted on a mitochondrial fragment of 2700 base pairs and on the lactate dehydrogenase locus of the nuclear DNA. Our results show higher introgression rates in the Ebro (Mediterranean) basin than in the Cantabrian rivers.

Key words

brown trout genetic introgression LDH-C* management mtDNA PCR-RFLP 


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Copyright information

© Springer 2005

Authors and Affiliations

  • María José Madeira
    • 1
  • Benjamín J. Gómez-Moliner
    • 1
  • Annie Machordom Barbe
    • 2
  1. 1.Facultad de Farmacia, Departamento de Zoología y Dinámica Celular AnimalUniversidad del País VascoVitoriaSpain
  2. 2.Departamento de Biodiversidad y Biología EvolutivaMuseo Nacional de Ciencias Naturales (CSIC)MadridSpain

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