, Volume 794, Issue 1, pp 73–92 | Cite as

Population genetics of pike, genus Esox (Actinopterygii, Esocidae), in Northern Italy: evidence for mosaic distribution of native, exotic and introgressed populations

  • Andrea Gandolfi
  • Claudio Ferrari
  • Barbara Crestanello
  • Matteo Girardi
  • Livia Lucentini
  • Andreas Meraner
Primary Research Paper


Esox flaviae represents the native esocid species of the Italian peninsula at present potentially highly threatened by the diffusion of exotic E. lucius. Here, we present a novel mtDNA (N = 272) and microsatellite (N = 275) dataset including 13 test and 3 reference samples, aimed to delineate the distribution of the native as well as the exotic species and to unravel potential introgressive hybridisation between the two species in Northern Italy. We highlight a complex mosaic distribution of both species, with contrasting occurrence even between neighbouring sites. Significant genetic substructure is still observed within E. flaviae, while the dispersal of the invader seems to be promoted by restocking actions. In addition, we prove the existence of introgressive hybridisation between native and exotic pikes. Here, gender-biased hybridisation is suggested, with native E. flaviae constituting the predominant ‘mother species’ in the hybridisation process. Finally, we underline the need for a revision of fisheries management regulations, for which a nation-wide and exhaustive genetic screening in the near future should build the scientific basis.


Esox flaviae Esox lucius Introgressive hybridisation Management Conservation 



The authors are grateful to Fisheries Offices (H. Erhard and H. Grund, Autonomous Provinces of Bolzano/Bozen; S. Filippini and R. Sala, Province of Lodi), researchers (E. Eschbach, Leibniz-Institute for Freshwater Ecology and Inland Fisheries, Department of Biology and Ecology of Fishes; T. Friedrich and G. Unfer, BOKU Vienna – University of Natural Resources and Life Sciences, Institute for Hydrobiology and Aquatic Ecosystem Management), free-lance ichthyologists (L. Betti; S. Rossi), professional fishermen (A. Andreis) and anglers (W. Arnoldo; Fisheries Association of Appiano/Eppan) who contributed to the collection of tissue samples.

Supplementary material

10750_2016_3083_MOESM1_ESM.pdf (107 kb)
NewHybrids analysis on a simulated dataset including individuals of E. lucius, E. flaviae and different hybrid classes (F1, F2 and backcrosses to E. lucius and E. flaviae). Supplementary material 1 (PDF 106 kb)


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Copyright information

© Springer International Publishing Switzerland 2017

Authors and Affiliations

  1. 1.Department of Biodiversity and Molecular Ecology, Research and Innovation CentreFondazione Edmund Mach (FEM)San Michele all’AdigeItaly
  2. 2.Department of Life SciencesUniversity of ParmaParmaItaly
  3. 3.Department of Chemistry, Biology and BiotechnologiesUniversity of PerugiaPerugiaItaly
  4. 4.Department of ForestryHunting and Fisheries Office of the Autonomous Province of BolzanoBolzanoItaly

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