Pyrrhula

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Bullfinches

Eurasian bullfinch

Scientific classification

Kingdom:	Animalia
Phylum:	Chordata
Class:	Aves
Order:	Passeriformes
Family:	Fringillidae
Subfamily:	Carduelinae
Genus:	Pyrrhula Brisson, 1760

Species

See text.

Pyrrhula is a small genus of passerine birds, commonly called Bullfinches, belonging to the finch family (Fringillidae).

The genus has a palearctic distribution. All species occur in Asia with two species exclusively in the Himalayas and one species, P. pyrrhula, also occurring in Europe. The Azores Bullfinch (P. murina) is an almost extinct species (about 120 pairs remaining), occurring only in the east of the island of São Miguel.

Analysis of the mtDNA cytochrome b sequence indicates that the holarctic Pine Grosbeak (Pinicola enucleator) is the closest living relative of this genus. Arguably, it could be included in Pyrrhula, but more probably is a distinct offshoot of a common ancestor, with the Pine Grosbeak as the sister group to the ancestor of the bullfinches (Arnaiz-Villena et al., 2001). The evolution of the bullfinch species started soon after the Pine Grosbeak's ancestors diverged from them (at the end of the Middle Miocene, about a dozen mya), and it is quite possible that the latter species evolved in North America; what is fairly certain is that the bullfinch radiation started in the general area of the Himalayas. The mountain finches also seem to be part of this clade (Marten & Johnson, 1986).

Bullfinches have glossy black wings and tail feathers. They show a white rump. The legs and feet are fleshy brown. Their short, swollen bill is adapted to eat buds, and is black except in P. nipalensis, which has a yellowish bill. The males can be distinguished by their orange or red breast. Some species have a black cap.

Bullfinch species are sedentary to migratory; probably most populations are partially migratory. Populations winter chiefly within the breeding range, those breeding at high levels tending to make altitudinal movements. Most migrants move short or medium distances, but some (apparently chiefly from Russia) move longer distances; in northern and central Europe, there is no evidence that northern populations move further than southern ones. North European birds move within a wider compass than central European birds. Bullfinshes are also eruptive migrants; numbers migrating show marked annual fluctuations; no link with particular food source has been established. Autumn migration begins late, and is fairly brief, mostly October-November; spring migration February-April.

The Eurasian Bullfinch population in Britain has been in serious decline since the mid-1970s, following a period of relative stability, and numbers have fallen by 62 per cent in 35 years. The decline was initially rapid, but has been shallower since the early 1980s. Nevertheless, the CES and BBS both suggest that the decline is continuing, at least in southern Britain. The demographic mechanism remains unclear (Siriwardena et al. 1999, 2000b), although agricultural intensification is suspected to have played a part. CES data indicate that productivity has increased over the last decade, and nest failure rates at the chick stage (15 days) have fallen from 37% to 21%.

[edit] Species

Pyrrhula aurantiaca Gould, 1858: Orange Bullfinch (Range : Kashmir)
Pyrrhula erythaca Blyth, 1862: Grey-headed Bullfinch (Range : Western China, Tibet)
Pyrrhula erythrocephala Vigors, 1832: Red-headed Bullfinch (Range: Himalayas)
Pyrrhula leucogenis Ogilvie-Grant, 1895: White-cheeked Bullfinch (Range : Philippines)
Pyrrhula murina du Cane Godman, 1866: Azores Bullfinch (Range : São Miguel Island, Azores)
Pyrrhula nipalensis Hodgson, 1836: Brown Bullfinch (Range : Himalayas, northern Myanmar and Northwest Yunnan)
Pyrrhula pyrrhula (Linnaeus, 1758): Eurasian Bullfinch (Range : very wide, from Asia to Europe)

[edit] References

Arnaiz-Villena, A.; Guillén, J.; Ruiz-del-Valle, V.; Lowy, E.; Zamora, J.; Varela, P.; Stefani, D. & Allende, L. M. (2001): Phylogeography of crossbills, bullfinches, grosbeaks, and rosefinches. Cellular and Molecular Life Sciences 58: 1159–1166. PDF fulltext