Genetically confirmed interbreeding between western Bonelli’s warbler (Phylloscopus bonelli) and wood warbler (P. sibilatrix)

Abstract

During May and June 2003, a mixed breeding pair consisting of a male western Bonelli's warbler (Phylloscopus bonelli) and a female wood warbler (P. sibilatrix) successfully raised six young in a broad-leafed forest near Jü nkerath, western Germany, an area far outside the regular breeding range of P. bonelli. The identity of the adult birds was confirmed by song, calls, colouration, and wing measurements. Based on blood samples taken from both parents and three juveniles, the potential interbreeding was analysed by molecular methods. Sequences of the mitochondrial cytochrome b gene differed between male and female by 8.7% and confirmed the identification of both parents. Sequences of the mitochondrial cytochrome b gene revealed that the male was a western Bonelli's and the female a wood warbler. The hybridisation and the parentage of male and female were corroborated by multilocus DNA fingerprinting. This is the first documented and genetically proven hybridisation event between these two warbler species.

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“…To date, the few studies about this species focused on other topics (i.e. genetics, acoustics or migration/distribution range) rather than on the breeding biology itself (Helbig et al 1995, Bremond 1976, Prince et al 1997, Dietzen et al 2007, Pilastro et al 2008. In contrast to other European Phylloscopus species whose breeding biology has been well studied (e.g.…”

Genetic differentiation of the Thorn‐tailed Rayadito Aphrastura spinicauda (Furnariidae: Passeriformes) revealed by ISSR profiles suggests multiple palaeorefugia and high recurrent gene flow

“…Given that prior knowledge of the target sequences flanking the repeat regions is unnecessary, ISSR markers are simpler to employ than SSR methods (Zietkiewics et al 1994). This technique has been used for population genetic studies (Gupta et al 1994), the evaluation of genetic variability in plant breeding (McGregor et al 2000), the classification of species in plant systematics (Treutlein et al 2003), and the detection of hybridization in birds, reptiles and plants (Wolfe et al 1998, Wink et al 2001, Dietzen et al 2007). In birds, ISSR co-migrating bands have shown to be informative diagnostic characters in conjunction with nucleotide sequences in intraspecific and closely related species comparisons (e.g.…”

Description of a new species of Phylloscopus warbler from Vietnam and Laos

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