READING 9 grade Сhemicals kill off song thrush

CHEMICALS KILL OFF SONG THRUSH

​The mysterious silencing of the song thrush has been unravelled by experts.

​They believe the dramatic decline of one of Britain’s most tuneful birds is due to a food shortage caused by modern farming methods.

​In the past 30 years, song thrush numbers have fallen by at least 65 per cent – about four million birds.

​And a report by the British Trust for Ornithology revealed that they may be literally starving to death in the bird equivalent of their teenage years because pesticides are killing off their staple diet of worms and snails.

​Experts who studied 90,000 song thrushes ringed since the 1960s found that far fewer young birds are getting through their first winter to join the breeding population.

​The drop in numbers has been less marked in Scotland where comparatively little farmland is subjected to intensive agriculture. The ornithologists found that before 1975 about half the young birds survived to breed. But from then until 1993 the survival rate dropped to only two in five.

​Many farmers claim the decline in song thrushes and skylarks, tree sparrows and grey partridges is due to an increase in predators such as sparrow-hawks and magpies.

​Dr David Thomson, admits that this cannot be ruled out. But he adds, “We are focusing our attention on the changes in agricultural practices which may be reducing the birds’ food supplies. These include pesticides, the removal of hedgerows and the reduction in ploughing in spring because so many crops are now sown in the autumn.”

​But while the song thrush has declined, the report also revealed that Britain’s population of rooks has increased by 39 per cent since 1975.

The experts believe that the dramatic decline of thrushes is due to ... .

CHEMICALS KILL OFF SONG THRUSH

​The mysterious silencing of the song thrush has been unravelled by experts.

​They believe the dramatic decline of one of Britain’s most tuneful birds is due to a food shortage caused by modern farming methods.

​In the past 30 years, song thrush numbers have fallen by at least 65 per cent – about four million birds.

​And a report by the British Trust for Ornithology revealed that they may be literally starving to death in the bird equivalent of their teenage years because pesticides are killing off their staple diet of worms and snails.

​Experts who studied 90,000 song thrushes ringed since the 1960s found that far fewer young birds are getting through their first winter to join the breeding population.

​The drop in numbers has been less marked in Scotland where comparatively little farmland is subjected to intensive agriculture. The ornithologists found that before 1975 about half the young birds survived to breed. But from then until 1993 the survival rate dropped to only two in five.

​Many farmers claim the decline in song thrushes and skylarks, tree sparrows and grey partridges is due to an increase in predators such as sparrow-hawks and magpies.

​Dr David Thomson, admits that this cannot be ruled out. But he adds, “We are focusing our attention on the changes in agricultural practices which may be reducing the birds’ food supplies. These include pesticides, the removal of hedgerows and the reduction in ploughing in spring because so many crops are now sown in the autumn.”

​But while the song thrush has declined, the report also revealed that Britain’s population of rooks has increased by 39 per cent since 1975.

​The decline of song thrushes has been less marked in ... .

CHEMICALS KILL OFF SONG THRUSH

​The mysterious silencing of the song thrush has been unravelled by experts.

​They believe the dramatic decline of one of Britain’s most tuneful birds is due to a food shortage caused by modern farming methods.

​In the past 30 years, song thrush numbers have fallen by at least 65 per cent – about four million birds.

​And a report by the British Trust for Ornithology revealed that they may be literally starving to death in the bird equivalent of their teenage years because pesticides are killing off their staple diet of worms and snails.

​Experts who studied 90,000 song thrushes ringed since the 1960s found that far fewer young birds are getting through their first winter to join the breeding population.

​The drop in numbers has been less marked in Scotland where comparatively little farmland is subjected to intensive agriculture. The ornithologists found that before 1975 about half the young birds survived to breed. But from then until 1993 the survival rate dropped to only two in five.

​Many farmers claim the decline in song thrushes and skylarks, tree sparrows and grey partridges is due to an increase in predators such as sparrow-hawks and magpies.

​Dr David Thomson, admits that this cannot be ruled out. But he adds, “We are focusing our attention on the changes in agricultural practices which may be reducing the birds’ food supplies. These include pesticides, the removal of hedgerows and the reduction in ploughing in spring because so many crops are now sown in the autumn.”

​But while the song thrush has declined, the report also revealed that Britain’s population of rooks has increased by 39 per cent since 1975.

​The farmers claim the increase of predators such as ... .