Freezing conditions take their toll on barn owl populations

But while conservationists at the British Trust for Ornithology (BTO) feared the trend would continue this month, the latest figures suggest barn owls which made it through the cold spell have been able to find food again.

Barn owls find it particularly difficult to find food when there is snow cover, which prevents them getting to their prey of small mammals.

The impact of the latest cold weather on the birds of prey comes after a poor breeding season last year, in which monitoring by the BTO showed brood sizes falling to their lowest levels for a decade.

It is thought the extremely cold weather last winter could have left females in a poor condition to breed, or even affected vole numbers.

This winter, the BTO received reports of 104 dead barn owls found with rings in December, compared to the 30 to 40 that the organisation would normally expect for the month.

There have been a further 31 reported so far in January, and while many other owls without rings are likely to have died, the figures give the Trust an idea of how the birds are faring. A spokesman for the Trust said: "Barn owls were affected badly, in fact hit quite hard, during December as a result of prolonged snow cover and freezing conditions.

"During the first week in January it looked like this trend might continue but the thaw set in and barn owls that survived the cold spell were able to find food."

And he said: "During the cold spell owls that could move did, and those that could would have moved to coastal marshes where the saline conditions allowed some ground free of snow cover."

He said there was anecdotal observations of barn owls returning to areas they had vacated.