Notes on the vocalizations of Buffy Tuftedcheek (Pseudocolaptes lawrencii)

In the following we briefly analyze and compare voice of the different races of Buffy Tuftedcheek (Pseudocolaptes lawrencii). 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) and Macaulay Library (ML).

Song of the 2 races, johnsoni ('Pacific Tuftedcheek') and lawrencii, seems to be quite different.

johnsoni: Song is a high-pitched rattled series of notes slowing into stuttering and ending (always) with a characteristic high-pitched downslurred note (overall not unlike a chasing call of some Hummingbirds, but obviously more powerful). Sometimes preceded by loud call notes, not clear if these are part of the full song.

lawrencii: Song is a number of well-spaced staccato notes (always present unlike johnsoni) followed by a trill, which  usually first ascends in pitch and then slightly descends while slowing down in pace. (A note of caution: this description is only based on 1 recording from Panama and 3 (of the same bird) from Costa Rica. Voice is however also described in Stiles and Skutch (1989), a reliable source for voice descriptions, and confirms the recordings)

There seems to be quite some variation in voice, especially when birds are excited (e.g. playback). johnsoni also utters a rattle which comes closer to lawrencii, but this doesn't seem to be the primary song.

Measurement of basic parameters of trilled part:

 johnsoni (n=7)

max. frequency                                   8500-10500Hz

note length at start                             0.015-0.03s

pace at start (over 5)                         0.2-0.38

note length towards end                    0.039-0.17s

pace towards end                               0.42-0.9

length downward slur                        0.2-1.14s (always present)

number of introductory notes             0,0,0,1,1,3,4

note shape                                           sharply descending at beginning and end of every note

lawrencii (n=4)

max. frequency                                   3050-4750Hz (but 7180Hz when excited)   

note length at start                             0.016-0.028s

pace at start (over 5)                         0.18-0.29

note length towards end                   0.033-0.06s (but 0.14s when excited)

pace towards end                               0.41-0.53 (but 0.94 when excited)

length downward slur                        never present

number of introductory notes            1(?), 3,4,4

note shape                                          all rounded overslurred notes

 

Assuming the few recordings of lawrencii are typical for the song of this race, we can conclude the following: Song of 'Pacific Tuftedcheek' johnsoni differs mainly from lawrencii by its much higher frequency (score 2), the presence of a long down-slurred ending note (score 2) and different shape of notes (score 1). This would lead to a total vocal score of 4 by applying Tobias criteria.

This note was finalized on 17th April 2015, using sound recordings available on-line at that moment. We would like to thank in particular the sound recordists: Andrew Spencer (with 3 of the 4 recordings of lawrencii) and Dodge Engleman (whose recording was published in Boesman 2011), and for johnsoni Nick Athanas, Olaf Jahn, Niels Krabbe, Mitch Leisinger, Oscar Marín Gomez, Manuel Sanchez, Andrew Spencer, Charlie Vogt and Julian Zuleta Marín.

 

References

Boesman, P. (2011). Birds of Costa Rica - MP3 sound collection. MP3-DVD. Belgium.

Stiles, F.G. & Skutch, A.F. (1989). A Guide to the Birds of Costa Rica. Christopher Helm, London.

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: on87_buffy_tuftedcheek.pdf