Press Association
Saturday 4th July 2009
Paving over front gardens and planting exotic ornamental plants could be contributing to the decline of one of Britain's best known birds, conservationists have warned.
The house sparrow has seen its population fall more than two-thirds (68%) in the past three decades and is disappearing from British cities such as London and Edinburgh, according to the RSPB.
Now research has suggested a lack of insects for the chicks to eat may be to blame for their urban decline.
The birds feed their young on insects such as aphids, and changes to British cities including increased traffic, development on green spaces, removal of trees and the conversion of front gardens for parking may all be leading to a drop in the abundance of bugs for the chicks to eat.
A three-year study of the species in Leicester by the RSPB, De Montfort University and Natural England found house sparrows were failing to rear enough young to sustain the population.
Many chicks were dying within the first week after hatching, or failing to survive once they had fledged.
And the research, published in the journal Animal Conservation, found chick survival was higher in areas where there were abundant aphids.
The study's lead author, Will Peach of the RSPB, said every pair of house sparrows had to raise at least five chicks a year to stop numbers falling - but in the study, many young sparrows were starving in their nests or too weak to live long after fledging.
Co-author Dr Kate Vincent, then of De Montfort University, Leicester, said the study showed the sparrow chicks were hatching but they were not surviving.
"This is partly down to the loss of green spaces within British cities through development on green space, tree removal and the conversion of front gardens for parking," she said. "The loss of deciduous greenery within urban areas may have made life much more difficult for birds like house sparrows that need large numbers of insects to feed their young."
