Notes on the vocalizations of White-naped Monarch (Monarcha pileatus)

In the following we briefly analyze and compare voice of the three races of White-naped Monarch (Monarcha pileatus). 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).

We haven't found any recordings of race buruensis, vocal comparison is thus limited to pileatus vs. castus. An overview of the vocalizations from the available recordings (with sonograms in the pdf version of this note):

Race pileatus

* one or a few raspy notes followed by a variable whistle

* a fast series of identical whistles

* a slower series of identical whistles

Race castus

* one or a few raspy notes followed by a variable whistle

* a repeated phrase of 3 whistles, the last one distinctly burry "pup-wheee-rrheeuw"

* a slightly rising bury whistle

If we assume the second vocalization of both races is homologous and a territorial song, then there are clear differences: A single whistle repeated vs. a short phrase of 2-3 different whistles repeated (score 3), with race castus clearly having longer whistles (duration, score 2). If we apply Tobias criteria this would lead to a total vocal score of 5. We should however bear in mind that this is based on only a few examples of this vocalization of both taxa, and the assumption that vocalisations are homologous. There is thus a fair amount of uncertainty and the case may be slightly more complex than suggested above, but it is definitely fair to say that vocabulary is clearly different.

The first vocalization type, of which there are more recordings, is rather a 'call'. Differences here are much less pronounced, although castus seems to have mainly an up and down whistle, while pileatus is much more variable.

This note was finalized on 21st January 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: Patrik Åberg, David Farrow, Frank Lambert and Mike Nelson.

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: on194_white-naped_monarch.pdf