[Monday 20 October 2008]
Observers in Britain have been shocked this
weekend by the news that a new species for Britain was watched by hundreds
of birders this autumn and identified by none of them.
Photographs of the Tophill falcon
clearly showed the white underwing. Photo: Roy Harvey (sorry
-could not send Roy's pic)
On 14 September Rare Bird Alert broke
the news that a male Red-footed Falcon had been reported at
Tophill Low Nature Reserve in East Yorkshire. The bird subsequently
settled in for a prolonged stay. With the invasion of the
species in spring this year it did not attract a
huge crowd of birders, but over the next month plenty of
people visited Tophill and both watched and photographed it.
On its arrival the falcon was
identified as a first-summer male Red-foot, and it was
clearly in moult, but no-one who saw it suspected what the moult
would reveal. On the evening of Saturday 18 October comments about
photos on the BirdGuides website were posted by one
astute observer, Ian Fisher, who noted that "a Red-foot should
either already have, or be moulting in black underwing coverts", rather
than white like those in the images. White underwing coverts are
diagnostic of male Amur Falcon, the lookalike east Asian
counterpart of Red-footed Falcon, and closer inspection of the images
appear to confirm this as the case.
Online bird forums and newsgroups buzzed
with speculation. Photographs were checked and the awful truth began to
dawn on British birders. Here was a mega that might have got away. News
that it had been seen as recently as Thursday 16 October
was small consolation for those who arrived on Sunday 19th to look for it,
as there was no sign all day.
Amur Falcon is very similar
to Red-footed Falcon, but the males display pure white underwing
coverts when adult. This individual still had dark-barred coverts which it
was in the process of moulting. Photos show these clearly and also show
the paler grey underparts than back, as well as a clear moustachial
stripe. All of these characters fit an Amur Falcon of that
age.
Amur Falcon breeds in eastern Asia and the
entire population migrates 11,000 km to winter in southern Africa, leaving
in September and often being seen in huge flocks. Previous records in the
Western Palearctic include an adult male in Sweden in June-July 2005, one
reported in Hungary in July 2006 and about six records for Italy from
the Straits of Messina, Sicily, on spring passage.
A previous record of Amur Falcon in Britain
involved a male bird originally ringed in south-west France in May
1984, but its origins were doubtful and both the French and British
record were subsequently rejected as doubtful.
Source: Birding Aus &
http://www.birdwatch.co.uk/website/content/view/1967/32/
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