Saturday 8 May 2010

HOUSE FINCH of unknown origin in West Cornwall

A singing male HOUSE FINCH (Carpodacus mexicanus) of the orange morph (frontalis) has been present on the Land's End peninsula (West Cornwall) since at least Tuesday 4 May. It is largely frequenting the private 'Swingates' garden just before the main Land's End complex and is generally very elusive and showing only from inside the grounds of the garden. It is good feather condition but is of unknown origin and provenance.

It represents only the second record of this North American passerine in Britain, following a female on Fair Isle (Shetland) from 27-30 April 1966 (Dymond 1991, The Birds of Fair Isle).

The UK400 Club accepted the Fair Isle occurrence on to Category E, believing it to be more likely of captive origin rather than a genuine vagrant. Although importation of birds from Mexico and elsewhere was rife in the 1960's, even now House Finches are commonly advertised for sale and kept fairly abundantly in captivity.

House Finches are predominantly sedentary but breed from Texas, through the western states, to British Columbia. In 1940, the species was introduced to New York from California (Aldrich & Weske 1978,
Origin and evolution of the eastern House Finch population. The Auk 95: 528-536) from where the species spread to many eastern areas from Arkansas to the Great Lakes. They winter within the breeding range as well as south to Mississippi and Alabama (Veit & Petersen 1993, Birds of Massachusetts) with ringing records in Massachusetts yielding movements to Virginia, Maryland and New Jersey. A further ringing programme in South Carolina saw movements to or from the more northerly regions, the maximum of which being 816 kilometres.

Aldrich & Weske noted that only 4% of their ringed birds moved as much as 200 kms but a much more recent study (that by Belthoff & Gauthreaux) found that female House Finches tended to migrate further than males (Proctor & Fisher 1999, Identification of House and Purple Finch and their separation from Common Rosefinch (Birding Scotland 2: 52-60).

There is also an additional House Finch record from The Netherlands - at Ijmuiden in January-February 1979 (Osieck in Birding World 1: 76-78)