Rare butterfly found breeding in Scotland for first time in 130 years

Eggs laid by white-letter hairstreak found on elm trees in Berwickshire

Patrick Barkham

Thu 15 Feb 2018 07.01 GMTLast modified on Thu 15 Feb 2018 07.03 GMT

The microscopic eggs of an endangered butterfly have been found in Scotland, suggesting the insect has returned to breed in the country for the first time in more than 130 years.

Lepidopterists discovered white-letter hairstreak eggs on wych elm trees at Lennel, Berwickshire, this month after an adult butterfly was spotted last summer 10 miles away – the first sighting in Scotland since 1884.

“Last year was an impossible find, but this year’s egg discovery is beyond anything we thought possible,” said Iain Cowe, butterfly recorder for the Borders, who found the adult butterfly last summer.

While most butterflies hibernate as caterpillars, the white-letter hairstreak spends nine months of the year as an egg, which is smaller than a grain of salt and stuck to slender branches of elm.

The eggs were detected by Jill Mills and Ken Haydock, volunteers for Butterfly Conservation who travelled from Bolton to scour trees in the Borders.

“We were searching the elm trees by the River Tweed at Lennel when Jill called me over,” said Haydock. “I could see by the look on her face that she had found something.

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