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Description:
The Goldcrest
is a really tiny bird, just six and a half grams in weight
when adult, this makes it some 20-30% smaller than the Chiffchaff.
Despite its energetic tit-like behaviour, it is still very
much a warbler in shape. The plumage is olive above and buff
white below, with darker wings displaying two white wing bars
and an orange or yellow crown stripe flanked by a black edge.
Adult males have an orange or orange-yellow crown stripe,
that in females is yellow and juveniles lack the crown strip
altogether.
Goldcrests have
a very high-pitched song that many people are unable to hear.
This is a shame because the song is sweet-sounding and it
is often the first or only indication that a Goldcrest is
present. The commonest call is an equally high-pitched ‘siii’
used to keep group members together.
Ecology & Behaviour:
Goldcrests are
serial nesters, the female regularly starting the second clutch
of eggs before the first brood of nestlings have fledged.
The male does the feeding while the female builds the new
nest. The nest itself is very neat and is basically a spherical
hammock positioned in the outer twigs of a spruce or fir tree.
This tremendous breeding effort can produce 20 chicks a year,
something that is essential given the very high winter losses
to cold weather. After very cold winters there may be only
a quarter of the previous autumn’s population left to
breed.
Such a tiny bird
would seem to be no candidate for long distance migration.
Our own birds wander but do not really migrate properly. However,
ringing has shown regular movements from countries around
the North Sea and Baltic into Britain for the winter. One
has even reached us from Russia and several from Poland, though
Norway, Sweden and Finland are their usual points of origin.
It seems amazing that any of them can survive two journeys
as well as the cold weather but some clearly do as several
Goldcrests ringed here in winter have been found back home
in Fennoscandia.
Garden BirdWatch links
Only a small number of gardens
report Goldcrests, partly because these birds can be very
hard to spot and because their song is so high-pitched.
A 'Focus On' article on the Goldcrest
appeared in issue 16 of the Bird
Table magazine. Garden BirdWatch participants can download
a copy of this article from the participant only pages.
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