Birds come and go in the garden. A
blackcap passed through last week but I have not seen any
bramblings or siskins yet. But there have been more
blackbirds. These may be locals attracted to the cotoneaster
berries and other offerings, but some could be foreigners.
One aspect of bird life that gets overlooked is that many of
our common residents are joined in winter by their foreign
relatives. We know about the obvious visitors from the north
like fieldfares, redwings and bramblings, but they are
accompanied by blackbirds, chaffinches, and even some wrens
and goldcrests, that mingle unobtrusively with the natives. Our native blackbirds are definite
stay-at-homes. Most never move more than a kilometre from
their birthplace and very few more than 20 kilometres.
However, 10-15 per cent of our winter population has come
from abroad, mainly from Scandinavia, the Netherlands and
Germany. These facts have come to light in a new
book The Migration Atlas, produced by the British
Trust for Ornithology. It is a weighty tome that analyses
the ringing records for every species. Some 1½ million
blackbirds have been ringed and 50,000 recovered. Seventy
five per cent of the recovered rings came from blackbirds
killed in the categories of
'human-related' or 'domestic predator' -
cars and cats, in other words. So you never know: the blackbird on your lawn may be from Finland, the starling next to it from Poland and the chaffinch under the birdtable from Russia. The attraction is the milder climate of our islands which are under the benign influence of the Gulf Stream. It seems that the birds are not worried by the extra rainfall!
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