Conservation Genetics

, Volume 8, Issue 2, pp 343–354 | Cite as

Detecting introgressive hybridisation in rock partridge populations (Alectoris graeca) in Greece through Bayesian admixture analyses of multilocus genotypes

  • Marina Barilani
  • Athanassios Sfougaris
  • Alexis Giannakopoulos
  • Nadia Mucci
  • Cristiano Tabarroni
  • Ettore Randi
Original Paper


The nominal subspecies of rock partridge (Alectoris graeca graeca) is widely distributed in Greece, where populations are declining due to over-hunting and habitat changes. Captive-reared chukars (A. chukar) have been massively released throughout the country, raising fear that introgressive hybridisation might have disrupted local adaptations leading to further population declines. In this study we used mtDNA control-region sequences and Bayesian admixture analyses of multilocus genotypes determined at eight microsatellite loci, to assess the extent of introgressive hybridisation in 319 wild rock partridges collected in Greece. A neighbour-joining tree split the mtDNA haplotypes into three strongly supported clades, corresponding to rock, red-legged (A.␣rufa) and chukar partridges. We did not detect any case of maternal introgression. In contrast, admixture analyses of microsatellite genotypes identified from four to 28 putative hybrids (according to different assignment criteria), corresponding to 1.2–8.8% of the samples, which were widespread throughout all the country. Power and limits of admixture analyses were assessed using simulated hybrid genotypes, which revealed that a small number of markers can detect all first and second generation hybrids (F 1 and F 2), and up to 90% of the first generation backrossess. Thus, the true proportion of recently introgressed rock partridges in Greece might be ca. 20%. These findings indicate that introgressive hybridisation is widespread, suggesting that released captive-bred partridges have reproduced and hybridised in nature polluting the gene pool of wild rock partridge populations in Greece.


Alectoris graeca and chukar Rock and␣chukar partridges Introgressive hybridisation mtDNA Control-region Microsatellites Bayesian admixture analysis 


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We deeply appreciated the collaboration of everybody who helped in sampling collection, and in particular: P. Alkon, S. Kark and N. Liu for sampling chukars in Israel and China; D. Dias and J.A. Perez Garrido for red-legged partridges from Portugal and Spain; P. Birtsas, the hunters and Forest Service personnel for sampling in Greece. Fundings for laboratory analyses were provided to ER by the INFS, Ministero per le Politiche Agricole e Forestali, and Ministero per l’Ambiente e la Tutela del Territorio, Direzione Conservazione della Natura. Special thanks to Lars Bach which sent us copy of the software HybridLab, to C. Primmer and two anonymous referees that greatly contributed to improve a first version of this paper.


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Copyright information

© Springer Science+Business Media B.V. 2006

Authors and Affiliations

  • Marina Barilani
    • 1
  • Athanassios Sfougaris
    • 3
  • Alexis Giannakopoulos
    • 3
  • Nadia Mucci
    • 1
  • Cristiano Tabarroni
    • 2
  • Ettore Randi
    • 1
  1. 1.Istituto Nazionale per la Fauna Selvatica (INFS)Ozzano Emilia (BO)Italy
  2. 2.Via Pertini 3, Casalecchio di RenoBolognaItaly
  3. 3.Laboratory of Ecosystem Management and Biodiversity, Department of Agriculture, Crop Production and Rural EnvironmentUniversity of ThessalyVolosGreece

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