In the following we briefly analyze and compare voice of the three races of Cinereous Conebill (Conirostrum cinereum). 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): fraseri (presumed dawn song, day-time song), nominate (day-time song) and littorale (day-time song).
All races have a song which typically consists of a subphrase of 2-3 notes repeated, with some small differences between repeats. Race litorale seems to have a day-time song with a much narrower freq. range (typically 3-5kHz, vs. 7-9kHz) and higher min. freq. (typically above 5kHz vs. above c. 2kHz). Apparently some exceptions do occur however.
A more in depth analysis would be needed to uncover any additional differences, and would require a larger set of recordings than presently available.
This note was finalized on 29th June 2016, using sound recordings available on-line at that moment. We would like to thank in particular the sound recordists who placed their recordings for this species on XC: Israel Aragon, Nick Athanas, Peter Boesman, Allen Chartier, Sandra Espinoza, Alvaro Jaramillo, Niels Krabbe, Dan Lane, Mitch Leisinger, Sjoerd Mayer, John V Moore, Mike Nelson and Joseph Tobias.
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: on387_cinereous_conebill.pdf