The production of hybrid falcons is very popular among bird breeders (Bunnell, 1986), but there are concerns that escaped specimens may interbreed in the wild (Everitt & Franklin, 2009; Lindberg & Nejse, 2002, Rodriguez et al., 2019). However, hybridization in the wild is rarely observed (Oliphant, 1991), because hybrid falcons are difficult to identify based on morphology (Eastham & Nicholls, 2005). A phylogenetic study indicated that hybridization might account for the observed genetic patterns in hierofalcons (Nittinger et al., 2007).
Hybrid falcons are also very popular in animal medical research (Abrams et al., 2001; Busquets et al., 2012; Lierz & Hafez, 2006; Lloyd & Wernery, 2008; Padrtova & Lloyd, 2009; Van Wettere et al., 2005).
Abrams, G. A., Paul-Murphy, J., Ramer, J. C. & Murphy, C. J. (2001). Aspergillus blepharitis and dermatitis in a peregrine falcon-gyrfalcon hybrid (Falco peregrinus X Falco rusticolus). Journal of Avian Medicine and Surgery 15, 114-120.
Bunnell, S. (1986). Hybrid falcon overview—1985. Hawk Chalk 14, 43-47.
Busquets, N., Bertran, K., Costa, T. P., Rivas, R., de la Fuente, J. G., Villalba, R., Solanes, D., Bensaid, A., Majo, N. & Pages, N. (2012). Experimental West Nile Virus Infection in Gyr-Saker Hybrid Falcons. Vector-Borne and Zoonotic Diseases 12, 482-489.
Eastham, C. P. & Nicholls, M. K. (2005). Morphometric analysis of large Falco species and their hybrids with implications for conservation. Journal of Raptor Research 39, 386-393.
Everitt, P. & Franklin, J. (2009). First UK record of a wild free-living Peregrine Falcon female breeding and producing young with a hybrid male falcon of domestic origin. Peregrine Falcon populations–status and perspectives in the 21st century. European Peregrine Falcon Working Group & Society for the Protection of Wild Animals, Warsaw, 585-592.
Lierz, M. & Hafez, H. M. (2006). Plasma chemistry reference values in hybrid falcons in relation to their species of origin. Veterinary Record 159, 79-82.
Lindberg, P. & Nejse, M. (2002). Lost falconers birds and hybrid falcons–do they have an impact on European Peregrine Falcon (Falco peregrinus) populations? A case study of lost falconers birds breeding in Sweden. I Raptors in the new millenium. In Proceedings of the world conference on birds of prey and owls 2000, pp. 107.
Lloyd, C. & Wernery, U. (2008). Humoral Response of Hybrid Falcons Inoculated With Inactivated Paramyxovirus-1 Vaccine. Journal of Avian Medicine and Surgery 22, 213-217.
Nittinger, F., Gamauf, A., Pinsker, W., Wink, M. & Haring, E. (2007). Phylogeography and population structure of the saker falcon (Falco cherrug) and the influence of hybridization: mitochondrial and microsatellite data. Molecular Ecology 16, 1497-1517.
Oliphant, L. W. (1991). Hybridization between a peregrine falcon and a prairie falcon in the wild. Journal of Raptor Research 25, 36-39.
Padrtova, R. & Lloyd, C. G. (2009). Hematologic Values in Healthy Gyr x Peregrine Falcons (Falco rusticolus x Falco peregrinus). Journal of Avian Medicine and Surgery 23, 108-113.
Rodríguez, B., Siverio, F., Siverio, M., & Rodríguez, A. (2019). Falconry Threatens Barbary Falcons in the Canary Islands Through Genetic Admixture and Illegal Harvest of Nestlings. Journal of Raptor Research, 53(2), 189-197.
Van Wettere, A. J., Wunschmann, A., Latimer, K. S. & Redig, P. T. (2005). Adenovirus infection in taita falcons (Falco fasciinucha) and hybrid falcons (Falco rusticolus x Falco peregrinus). Journal of Avian Medicine and Surgery 19, 280-285.