In the following we briefly analyze and compare voice of the two races of Ringed Warbling-finch (Poospiza torquata). 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 (illustrated with multiple sonograms in the pdf version of this note): nominate and pectoralis.
nominate (n=4) has a song consisting of a repeated subphrase, which typically has 4-6 well separated notes (1.8 - 2.2 notes/s). This song typically lasts for long periods (1 minute or more). pectoralis has a song consisting of a short phrase of some 7-10 notes (2.2 - 3.0 notes/s, trills counted as 1) without any repetition, and typically having a single trilled note in the phrase. Song phrase duration c. 3-4s. Only rarely a longer song is given (max. 8s) , in which a subphrase of 6-8 notes is repeated a couple of times. Frequencies and note shapes of both races very similar.
There is thus a striking difference in song length, with nominate having a very long string of repeated subphrases, while pectoralis typically has a short single song phrase (song duration, score 3), occasionally doubled or tripled. pectoralis also has a faster pace of delivery (2) and always has at least a trilled note in its song phrases. Application of Tobias criteria would lead to a total vocal score of about 5. Some caution is needed however, given there are only 4 recordings of nominate, and a recording from S Bolivia is of unknown racial identity. More recordings of nominate are needed to confirm these findings.
This note was finalized on 4th July 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: Nick Athanas, Peter Boesman, Miguel Castelino, Niels Krabbe, Dan Lane, Bernabe Lopez-Lanus, Aidan Maccormick, Sjoerd Mayer, Paul Smith and Joseph Tobias.
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: on399_ringed_warbling-finch.pdf