Good news on the bird population—but not for everyone
Mar 9th 2013
BRITISH birdwatchers are used to bad news. House sparrow
numbers have fallen from an estimated 30m to 10m since 1966. Curlews have
become a rare sight, their numbers plummeting by 50% in 15 years. Cuckoos,
once-frequent visitors from Africa , have
declined by 63% in the south-east in the past two decades. Earlier springs that
confuse migratory birds, more efficient farming and the conversion of
dilapidated buildings (good for nesting) into modern homes have all contributed
to these woes.
But data released by the British Trust for Ornithology
(BTO), a research charity, suggest some are soaring. Tracking bird populations
by means of regular surveys, the figures give the clearest picture yet of 49
species across Britain .
Blackcaps, small woodland birds native to Germany
and eastern Europe, are lingering after their summer sojourns: since 1967
numbers have increased by 177%. The little egret, a white heron-like bird,
arrived from continental Europe in 1989 and
now numbers over 5,000. Wood pigeons, once found shyly cooing in forests, have
boldly moved into cities and suburbs.
Environmental and agricultural changes have helped as well
as disoriented birds. Modern farming techniques allow grain to be sown in the
autumn rather than the spring; that helps wood pigeons feed in winter. Warmer
winters mean rivers and ponds are less likely to freeze, providing the little
egrets with food. James Pearce-Higgins of the BTO says that blackcaps benefit
particularly from the increasing popularity of berry bushes (such as rowan and
yew) in people’s gardens.
These species and others benefit from the British love of
bird feeders. “I would be amazed if anyone feeds garden birds in Europe as much as we do,” says Stephen Moss, a nature
writer. First sold in 1964 by the Royal Society for the Protection of Birds
(RSPB), a charity with over 1m members, bird feeders took off in the 1990s when
food such as sunflower hearts and nyjer seeds became widely available and the
RSPB began to encourage people to feed birds throughout the year. (The bird
tables found in other northern European countries, such as Finland and Germany , tend to be stocked only
during the winter.) In 1987 only 17 species availed themselves of British
feeders; these days 86 do.
Birders grouse nonetheless. Some of the species
prospering, such as carrion crows and buzzards, are disliked. And migratory
birds that extend their visits may provide competition for some avian natives.
They are “muscling in and getting the first claim on breeding sites”, says
Richard Cowser of the Sussex Ornithological Society. Like their human
counterparts, residents of a small island buffeted by global winds, British
birds will have to learn to compete.
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