European Journal of Wildlife Research

, Volume 56, Issue 3, pp 239–248 | Cite as

Experimental evaluation of live cage-traps for black-billed magpies Pica pica management in Spain

  • Francisco Díaz-Ruiz
  • Jesús T. García
  • Lorenzo Pérez-Rodríguez
  • Pablo Ferreras
Original Paper


Black-billed magpies (Pica pica) are considered as a nest predator of game and non-game birds in Europe. In rural areas of Spain magpie control is commonly used as a management tool in small game hunting estates. Cage-traps with a magpie as a decoy are the legal method most commonly used for controlling magpies in Spain although its performance has not yet been experimentally tested. We evaluated the selectivity, efficiency, and the effect of different factors on capture rate of these traps for magpie control and determine the effect of magpie removal on magpie density. Only four out of 197 captures corresponded to non-target species, which were released unharmed. Since the release of non-target captures depends on the daily checking of the trap and the trapper commitment, in order to guarantee the efficiency and selectivity of this method traps should be revised daily by full time, qualified trappers. The efficiency of this method is high during the breeding season, reducing magpie density in the area where the control is performed. Highest capture rates were obtained in the first days after cage-traps setting. Neither the gender nor the origin (local or foreign) of the decoy significantly affected the capture rate. Among male decoys, experimentally increased testosterone levels did not increase capture rates. According to our results, the tested cage-traps with a living decoy could be employed as an efficient and selective method for magpie population management in Spain, when used by full time, qualified trappers.


Cage-traps Capture rate Black-billed magpie Selectivity Predator management 



This study was funded by Consejería de Medio Ambiente of Junta de Comunidades de Castilla-La Mancha (project PREG-05-23). Patrick Fasolo kindly provided the first magpie decoys to start the trapping experiments, and shared with us his long experience with the use of the traps. Land owners and game owners of both study areas facilitated the access to estates and facilitated the field tests. Salvador Luna performed most of the field work. Luis Enrique Mínguez kindly assisted in the field work and solved most bureaucracy during the project development. Beatriz Arroyo provided helpful support with the statistical analyses.

All the experiments comply with the current Spanish laws, and were performed with the corresponding legal authorizations and following current guidelines for animal welfare.


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Copyright information

© Springer-Verlag 2009

Authors and Affiliations

  • Francisco Díaz-Ruiz
    • 1
  • Jesús T. García
    • 1
  • Lorenzo Pérez-Rodríguez
    • 1
    • 2
  • Pablo Ferreras
    • 1
  1. 1.Instituto de Investigación en Recursos Cinegéticos, IREC (CSIC-UCLM-JCCM)Ciudad RealSpain
  2. 2.School of Biological SciencesUniversity of AberdeenAberdeenUK

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