Sex determination in barn swallows Hirundo rustica by means of discriminant analysis in two European populations

Research output: Contribution to journalArticle


Aims: Differences in morphology in adult barn swallows were investigated using bone and feather measurements taken from birds from a northern (Danish) and a southern (Spanish) European population. Discriminant Function Analysis was used to help in discriminating the sex of individuals of both populations. Location: Badajoz (Spain) and Kraghede (Denmark). Methods: Two discriminant functions were obtained using biometric data from adult individuals, one for each European population. These functions were validated using external data from a sample of an Italian and Ukrainian barn swallow populations. Results: Three morphometric variables: the length of the outermost tail feathers, the length of the inner tail feathers and the length of the keel were retained in the discriminant function in the two populations studied. Overall, these functions allowed us to determine the sex of adult birds with 90.1 % and 91.9 % accuracy for the Spanish and the Danish populations, respectively External validation using a sample from the Italian population to validate Spanish discriminant function and from the Ukrainian population to validate the Danish discriminant function showed that 91 % of Italian and 86 % of Ukrainian swallows were correctly classified. Conclusions: The two discriminant functions obtained would be highly valuable in future work carried out on this species because it would allow researchers to determine the sex of individuals shortly after arrival to the breeding areas without having to wait for the beginning of courtship or incubation for reliable sexing.


  • Ignacio G. Hermosell
  • Javier Balbontin
  • Alfonso Marzal
  • Maribel Reviriego
  • Florentino de Lope
Research areas and keywords

Subject classification (UKÄ) – MANDATORY

  • Ecology


  • sexing, discriminant, barn swallow, biometry
Original languageEnglish
Pages (from-to)93-100
Issue number1
Publication statusPublished - 2007
Publication categoryResearch