Swallows’ early arrival may be due to global warming

SWALLOWS are returning to Ireland earlier and earlier each year to nest, possibly because of increasing temperatures.

A Spring Alive study by Birdwatch Ireland has revealed that the more than 500,000 birds that come to our shores each year now arrive two weeks earlier than 20 years ago. Most of the birds, generally from South Africa, arrive near the end of April.

Niall Hatch of Birdwatch Ireland says they think there is a direct link between increasing temperatures and the availability of food.

“They live solely on flies and water and they wait until there is an increase in temperature, so there is an availability of food. Our study shows that they are arriving on average about two weeks earlier than they did 20 years ago and that’s probably because of global warming,” he said.

Niall said there had been reports of lone swallows in Wicklow, Wexford and even Donegal, while there was also a report of a bird in Cork in February. “That was freakishly early,” he said, adding that the rest are gathering in France, Spain and Portugal for the final leg of their journey.

The Spring Alive project is also examining the migratory patterns of other Irish favourites, including the cuckoo and the swift.