‘Remarkable’ sign of climate change as swallows remain in UK for winter

SWALLOWS are now staying in the UK for winter due to climate change, according to new research.

The arrival of the birds in Britain traditionally marks the start of spring, and inspired the phrase “one swallow does not make a summer”. Now experts have revealed that some swallows are deciding to stay in the UK through the winter months rather than fly back to Africa to avoid the cold.

A dozen birds have been reported in January, mainly in the south and south-west of Britain and Ireland.

Professor Juliet Vickery, chief executive of the British Trust for Ornithology (BTO), said: “It is indeed remarkable. The change in behaviour is one of the most remarkable signs yet of the warming world being caused by climate change.

“We haven’t got to go back too far to remember winters when it would have been impossible for swallows to survive the freezing temperatures, but as our winters get milder, it is something we may see more and more.”

Traditionally, swallows head south at the end of summer because the European winter is too cold for the flying insects on which they feed.

Just how long this has been going on is typified by a famous Greek vase from 500BC that shows three men looking up at a returning swallow with the caption “spring already”.

But with the run of mild winters in recent years, a small number of swallows have been able to attempt to spend the winter months here.

The BTO’S Birdtrack survey of birdwatchers’ regular observations has received almost 100 reports of up to 12 individual swallows between January 1 and February 1.

Professor James Pearce-higgins, the BTO’S director of science said: “To suggest our winters would be warm enough for swallows to survive would have been unthinkable a few decades ago. But the evidence that our climate is changing is building year by year.”

Where the swallow went for the winter has only been known for just over a century with the introduction of bird ringing.

In December 1912, a swallow was caught on a farm in South Africa, bearing a ring that had been placed on its leg 18 months earlier in Staffordshire. This proved a bird not much bigger than a matchbox could undertake an immense annual journey of 6,000 miles.