The Alpine Accentor

Posted by Myla | Added on : July 18, 2010 03:16am | Last edited: July 18, 2010 03:17am | Viewed 3873 times | 0 Comments

This bird is most closely related to, and forming a species group with, P. himalayana; the two are sometimes placed in a separate genus,Laiscopus, because of larger size and distinct plumage differences in comparison with current congeners. Birds from Corsica, described as race tschusii, considered inseparable from nominate. Nine subspecies recognized.

The Alpine Accentor, Prunella collaris, is a small passerine bird found throughout the mountains of southern temperate Europe and Asia at heights above 2000 m. It is mainly resident, wintering more widely at lower latitudes, but some birds wander as rare vagrants as far as Great Britain.

It is a bird of bare mountain areas with some low vegetation. It builds a neat nest low in a bush or rock crevice, laying 3-5 unspotted sky-blue eggs.

This is a Robin-sized bird at 15-17.5 cm in length, slightly larger than its relative, the Dunnock. It has a streaked brown back, somewhat resembling a House Sparrow, but adults have a grey head and red-brown spotting on the underparts. It has an insectivore's fine pointed bill.

Sexes are similar, although the male may be contrasted in appearance. Young birds have browner heads and underparts.

The mating system is of particular interest. Home ranges are occupied by breeding groups of 3 or 4 males with 3 or 4 females. These are unrelated birds which have a sociallypolygynandrous mating system. Males have a dominance hierarchy, with the alpha males being generally older than subordinates. Females seek matings with all the males, although the alpha male may defend her against matings from lower ranking males. In turn, males seek matings with all the females. DNA fingerprinting has been used to show that, within broods, there is often mixed paternity, although the female is always the true mother of the nestlings raised within her nest. Males will provide food to chicks at several nests within the group, depending on whether they have mated with the female or not - males only provide care when they are likely to be the true fathers of the chicks.

This species has an extremely large range, and hence does not approach the thresholds for Vulnerable under the range size criterion (Extent of Occurrence <20,000 km2 combined with a declining or fluctuating range size, habitat extent/quality, or population size and a small number of locations or severe fragmentation). The population trend appears to be stable, and hence the species does not approach the thresholds for Vulnerable under the population trend criterion (>30% decline over ten years or three generations). The population size is very large, and hence does not approach the thresholds for Vulnerable under the population size criterion (<10,000 mature individuals with a continuing decline estimated to be >10% in ten years or three generations, or with a specified population structure). For these reasons the species is evaluated as Least Concern.

Prunella collaris is a widespread but patchily distributed resident in mountainous areas of central and southern Europe, which accounts for less than half of its global range. Its European breeding population is relatively large (>100,000 pairs), and was stable between 1970–1990. Although there was no trend information available for the sizeable populations in Spain, France, Italy and Russia, trends elsewhere in Europe during 1990–2000 were stable, and the species probably remained stable overall. Consequently, it is provisionally evaluated as Secure.