14/03/2019
The
British Ornithologists' Union Records Committee (BOURC) has added 'Richardson's
Cackling Goose', the hutchinsii subspecies of Cackling
Goose, to its British list.
The
addition is based on the well-documented occurrence of a bird with Pink-footed
Geese at Holkham Freshmarsh, Norfolk, from 6-23 February 1999.
After
many years of debate some clarity about the taxonomic relationships,
identification and distribution of the North American 'white-cheeked' geese of
the genus Branta has been achieved (North American Birds 62,
344-360, British Birds 109: 677-684). This allowed for the acceptance of Cackling Goose to the BOU's British list in
March 2016. However, at that time, it was felt that the first British
record, from Lancashire in November 1976, could not be conclusively identified
to subspecies.
Following
this decision, a number of candidates were considered by BOURC for
subspecies-level acceptance, resulting in a unanimous decision that the Holkham
Freshmarsh individual from February 1999 showed features consistent with the
subspecies B h hutchinsii. Furthermore, there was no evidence of a captive
origin, with the bird seen in a flock of Pink-footed Geese, a plausible carrier
species for a vagrant crossing the Atlantic. Thus the record and subspecies was
accepted to Category A.
Richardson's
Cackling Goose breeds in north and central Canada and Greenland, migrating to
winter in Texas, USA and Mexico.
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