Notes on the vocalizations of White-winged Becard (Pachyramphus polychopterus)

In the following we briefly analyze and compare voice of the different races of White-winged Becard (Pachyramphus polychopterus). 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).

White-winged Becard has a typical song, but also has quite some 'variants' of this song. This would make a thorough analysis over the 9 subspecies quite complicated and time-consuming. In order to save time, we have tackled this case in a somewhat different way: we have looked for 1-2 randomly selected recordings of typical song for every race. If these are nearly identical, then it is very unlikely there will be a significant vocal difference.

Typical song is a single plaintive note followed by a series of 4-6 similar notes after a somewhat longer pause, the series starting usually with 2 notes delivered fast (or these 2 linked into a modulated note), then slowing down towards the end. All notes downslurred. "tew...tew-tu..tew..tew..tew". First note has largest frequency range.

 

P. p. similis (C Guatemala E to S Belize (Toledo) and N Honduras, S to N Colombia (N Chocó)). Selected recording: XC107784

max. freq.                             3440Hz 

min. freq.                              2000Hz

length 1st note                    0.14s

length 1st pause                  0.22s

# of notes                             9

length last pause                 0.11s

total length                           1.52s

P. p. cinereiventris (N Colombia (Chocó except extreme N, E to Santa Marta, S to upper R Sinú and César). Selected recording: XC17258

max. freq.                             3220Hz

min. freq.                              2100HZ

length 1st note                    0.14s

length 1st pause                  0.26s

# of notes                             6

length last pause                 0.096s   

total length                           1.55s

P. p. dorsalis (C & SW Colombia (S Antioquia and Cundinamarca S to SW Nariño) and NW Ecuador (E Esmeraldas, N & W Imababura, and N Pichincha S to Mindo area). Selected recording: XC11292

max. freq.                             3750Hz

min. freq.                              2080Hz

length 1st note                    0.17s

length 1st pause                  0.14s

# of notes                             8

length last pause                 0.12s     

total length                           1.78s

P. p. tristis (NE Colombia (E of Andes from Norte de Santander S to Boyacá, probably to Guainía), Venezuela (except Cerro Duida, in S Amazonas), Trinidad and Tobago, the Guianas and NE Brazil (Roraima E to Maranhão and SE Pará)). Selected recordings: XC221597, XC192112

max. freq.                             3400Hz

min. freq.                              1850-1900Hz

length 1st note                    0.11-0.13s

length 1st pause                  0.19-0.25s

# of notes                             6-7

length last pause                 0.10-0.14s           

total length                           1.35-1.44s

P. p. nigriventris (E Colombia (E of Andes in W Meta S to Vaupés), S Venezuela (S Amazonas at base of Cerro Duida), W Brazil (both banks of upper Amazon E to R Jamundá and E bank of R Madeira), E Peru (S of R Marañón) and N Bolivia (Beni)). Selected recording: XC227168

max. freq.                             3370Hz

min. freq.                              1880Hz

length 1st note                    0.12s

length 1st pause                  0.24s

# of notes                             7

length last pause                 0.13s

total length                           1.39s

P. p. tenebrosus (SE Colombia (SE Nariño and W Caquetá E to Amazonas), E Ecuador and NE Peru (N & W Loreto and San Martín)). Selected recording: XC259049

max. freq.                             3390Hz

min. freq.                              1880Hz

length 1st note                    0.14s

length 1st pause                  0.27s

# of notes                             6 (7)

length last pause                 0.17s

total length                           1.35s

P. p. polychopterus (E Brazil (Piauí and Ceará S to Alagoas and Bahia)). Selected recordings: XC227172, XC7449

max. freq.                             3500-3700Hz

min. freq.                              1850-1870Hz

length 1st note                    0.095-0.11s

length 1st pause                  0.24-0.25s

# of notes                             5

length last pause                 0.12-0.16s

total length                           1.07-1.37s

P. p. spixii (NW Bolivia (Pando and La Paz E to Santa Cruz and S to Tarija), S & SE Brazil (Mato Grosso E to Espírito Santo, S to Rio Grande do Sul), Paraguay, N Argentina (S to Tucumán, Córdoba and N Buenos Aires) and Uruguay). Selected recordings: XC115719, XC227171,XC32332
max. freq.                             3250-3550Hz

min. freq.                              1800-1900hz

length 1st note                    0.12-0.14s

length 1st pause                  0.20-0.25s

# of notes                             5-6

length last pause                 0.09-0.12s

total length                           1.16-1.42s

 

It is clear that if one looks for 'typical songs', they are indeed very similar among races (with the exception of dorsalis, for which we didn't find a true 'typical song' among the few available recordings). While the above is no proof for lack of vocal differences, it greatly reduces the possibility that any race has a significantly different song.  

This note was finalized on 17th July 2015, using sound recordings available on-line at that moment. We would like to thank in particular the many sound recordists who placed their recordings for this species on XC.

 

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: on113_white-winged_becard.pdf