Birds such as blue tits and great tits have suffered as a result of this year's unusually rainy summer, the British Trust for Ornithology (BTO) has said.

Numbers of blue tits monitored were a staggering 48 per cent lower than would normally be expected in an average year, while great tits were down 33 per cent and reed warblers 27 per cent.

The whitethroat, willow warbler, treecreeper and willow tit also had the lowest number of surviving chicks since the BTO began recording bird numbers 25 years ago.

It is thought that a shortage of food has fuelled the decline in numbers and the BTO speculated that young chicks would have died because they did not have enough feathers to protect them from the heavy downpours.

The BTO's Mark Grantham said: "The cold, wet weather over the early summer will have made life incredibly tough for adults that still had hungry youngsters in boxes," Reuters reports.

"Each blue tit chick (up to 12 in a box) will need around 100 caterpillars every day, and finding enough caterpillars in the poor weather we've seen is no mean feat."

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