In the following we briefly analyze and compare voice of the two races of Yellow-bridled Finch (Melanodera xanthogramma). We also try to quantify the extent of any vocal differences using the criteria proposed by Tobias et al. (2010), as a support for taxonomic review. We have made use of sound recordings available on-line from Xeno Canto (XC).
A comparison of song of both races (illustrated with sonograms in the pdf version of this note): barrosi and nominate.
Song of both races is very similar, a leisurely delivered sequence of single melodious notes, typically some 3-4 different notes which are repeated as a subphrase. Song of nominate may include buzzy or burry notes, which apparently is not the case in barrosi (although this would have to be confirmed by more samples). Pace and frequency range are very similar, at most nominate sings slightly faster (but this again would have to be confirmed by more samples)
This note was finalized on 30th June 2016, using sound recordings available on-line at that moment. We would like to thank in particular the sound recordists who placed their song recordings for this species on XC: George Armistead, Bernabe Lopez-Lanus, Fabrice Schmitt, Jacob Socolar and Andrew Spencer.
References
Tobias, J.A., Seddon, N., Spottiswoode, C.N., Pilgrim, J.D., Fishpool, L.D.C. & Collar, N.J. (2010). Quantitative criteria for species delimitation. Ibis 152(4): 724–746.
More Information: on391_yellow-bridled_finch.pdf