PINK-TAILED BUNTING  Urocynchramidae
The Pink-tailed Bunting is an enigmatic passerine that is endemic to the mountains of central-west China. Because of the structure of its horny palette, it has generally been classified as an emberizid bunting (e.g., Sibley & Monroe 1990, MacKinnon & Phillipps 2000). Its behavior and habitat, though, and the pink in the body plumage recall rosefinches, and many birders who have seen it thought it was likely a rosefinch (e.g., Ben King in Groth 2000, Paul Holt, pers. obs., Clement et al. 1993). I thought the short snippet of song also recalled rosefinches but Przewalski (1876), who first collected and described it, thought the song was bunting-like. Dickinson (2003), in his recent edition of the Howard & Moore world checklist, listed it among the rosefinches [and called it Pink-tailed Rosefinch], next to Long-tailed Rosefinch Uragus sibiricus, the species it most recalls.

When I was in China in June 2004 on a Sunbird tour with Paul Holt, and took the photos on this page, we all assumed that the controversy was between a finch and a bunting, and nothing more. None of us had read the biochemical evidence published by Groth (2000). And that evidence is compelling the bird is neither bunting nor finch, but something unknown. Its lineage goes back deep within the Passeroidea assemblage and, so far, it appears to have no extant close relatives. Groth (2000) concludes his paper this way: "I agree with Domaniewski (1918) and Wolters (1979) that Urocynchramus belongs in its own family, the Urocynchramidae." The old papers cited are in German but apparently this is not a new idea. Rather, it now has strong biochemical support. Strangely, Dickinson (2003) cites the Groth paper in footnotes but does not reveal or discuss the findings!

Pink-tailed Bunting/Rosefinch/whatever is a resident of alpine scrub at high elevations. We found a pair along the top of the hillside shown below, sitting atop the short shrubs with the male singing for short periods. The pair would then fly on to another dwarf willow for a bit of song, a bit of looking around. This is at an elevation of over 10,000' (>3050m). Clement (1993) lists its elevational range as 3050-5000m where it occurs "mainly in pairs or singly, but outside the breeding season small flocks of five to ten occur."

It was only recently that my interest in this taxon was awakened by the publication of an oscine passerine supertree by Jønsson & Fjeldsa (2006). They reviewed 97 recent studies of passerine relationships that were based on DNA evidence, assessed the strength of the evidence, and constructed a cladogram of relationships based on the evidence to date. I was shocked to find that Pink-tailed Bunting was in its own Passeroidea clade in other words, the evidence to date suggests it arose in a difference lineage than any other of the passerines. They also note that this taxonomic position has not been thoroughly researched or well sampled, and does not yet have high Bayesian or bootstrap support. So this is a question that deserves further analysis.

Yet, the evidence to date shows that Pink-tailed Bunting is neither a finch nor a bunting. Groth (2000) points out some anomalies morphologically. Most important is the fact that this bird has ten primaries; the outermost primary is half the length of the 9th primary, but still is a usable primary. All other fringillids and emberizids have only 9 primaries (the 10th is vestigial). While the evolution of the nine-primaried wing is a derived condition, no other bird in the nine-primaried group has undergone a character reversal to a ten-primaried state. This alone suggests something is quite different about this bird. Another oddity is the pink in the tail (which can be seen in these photos). If this bird were a rosefinch, it would differ from all rosefinches on this character. For these reasons Paynter, in the Peters' checklist series, doubted it was a cardueline finch (Groth 2000).

Obviously, there is much more to learn about this bird. Its biology and breeding ecology are essentially unknown. Clement et al. (1993) refer to it as a "shy and little-known species from central China." I feel quite fortunate at having photographed this interesting little bird.

Photos: The Pink-tailed Bunting Urocynchramus pylzowi was photographed near Heimaihe, above Qinghai Lake, Qinghai, China, on 19 June 2004. All photos © 2006 Don Roberson; all rights reserved.

Bibliographic notes

There is no "family book" covering this enigmatic bird; indeed, as pointed out above, there is not yet a scientific consensus that this is a family. And yet the evidence is tending that way . . . 

Literature cited:

Clement, P., A. Harris, and J. Davis. 1993. Finches and Sparrows: an Identification Guide. Princeton Univ. Press, Princeton, N.J.

Dickinson, E.C., ed. 2003. The Howard & Moore Complete Checklist of the Birds of the World. 3d ed. Princeton Univ. Press, Princeton, N.J.

Groth, J.G. 2000. Molecular evidence for the systematic position of Urocynchramus pylzowi. Auk 117: 787-791.

Jønsson, K.A., and J. Fjeldså. 2006. A phylogenetic supertree of oscine passerine birds. Zoologica Scripta 35: 149-186.

MacKinnon, J., and K. Phillipps. 2000. A Field Guide to the Birds of China. Oxford Univ. Press, Oxford.

Przewalski, N.M. 1876. Mongoliia i stran Tangutuv, vol. 2. Russkago Obva, St. Petersburg, Russia.

Sibley, C. G., and B.L. Monroe, Jr. 1990. Distribution and Taxonomy of Birds of the World. Yale Univ. Press, New Haven, CT.



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