Ireland’s much loved puffins are in decline because they’re so tired from transatlantic flights.

The iconic bird is found in many other European countries and North America, but a study by University College Cork and Oxford University revealed that (much like the Irish people themselves) Irish puffins have a greater fondness for travel than their next-door neighbors.

Whereas American puffins might only travel a few hundred miles, scientists found that Irish birds travel up to 29,000 miles zig-zagging across the Atlantic to feast in the rich waters of Canada and Greenland.

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Dr Mark Jessopp from UCC said the birds’ passion for travel was impressive but it likely meant by the time they return to Ireland in April they’re too tired to breed; often mates will hatch only one egg and will struggle to rear even this solitary infant to adulthood.

Great views of #puffins in the inky waters around Inishnabro, Blasket Islands #Kerry this week during @MfrcGmit fieldwork #seabirdersaturday

— Niall Keogh (@nialltkeogh) July 15, 2017

All of which has led to population decline.

“There are other factors – such as rats on the Saltee islands off Wexford which has seen the puffin colony crash from 2,000 to 50 birds,” Jessopp told the Irish Times.

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Another factor is the use of Skellig Michael for the filming of 'Star Wars.' The island attracted global attention as one of the movie’s dramatic locations, but Jessopp believes the arrival of so many people all at once “would not help” the birds breed.

These adorable puffins found on the island of Skellig Michael don't seem too bothered that Star Wars was filmed on top of their house.

— Andrew Lanxon Hoyle (@Batteryhq) October 31, 2017

In 2015 the International Union for Conservation of Nature warned that the Atlantic puffin was at risk of extinction. Prompting Martin Harper, conservation director of Britain’s Royal Society for the Protection of Birds, to warn, “Today’s announcement means that the global wave of extinction is now lapping at our shores. The number of species facing extinction has always been highest in the tropics, particularly on small islands. But now the crisis is beginning to exact an increasingly heavy toll on temperate regions too, such as Europe.”

Skellig Michael is home to thousands of Atlantic puffins, What a picture byIG/instaireland

— (@discoverirl) August 6, 2016