Butterfly egg detectives’ rare find

Amateur naturalists Ken Haydock and Jill Mills at Lennel where they found White-letter Hairstreak eggs were found on Wych Elm trees.
Amateur naturalists Ken Haydock and Jill Mills at Lennel where they found White-letter Hairstreak eggs were found on Wych Elm trees.

A butterfly which has been on the decline looks like it has started breeding in Scotland for the first time in 130 years.

Amateur naturalists Ken Haydock and Jill Mills suspected that butterfly eggs they found on wych elms at Lennel near Coldstream earlier this month were those of the White-letter Hairstreak butterfly and Butterfly Conservation has since confirmed the find.

White-letter Hairstreak Satyrium w-album

White-letter Hairstreak Satyrium w-album

The discovery comes months after Borders butterfly recorder Iain Cowe spotted an adult White-letter Hairstreak at Paxton - the first sighting in Scotland since 1884.

Iain said: “The discovery of these eggs is hugely significant as it not only confirms the White-letter Hairstreak is breeding here, but one of the eggs was an old, hatched shell – so it looks like the butterfly could have been breeding here since at least 2016.

“Last year was an impossible find, but this year’s egg discovery is beyond anything we thought possible.”

The butterfly’s caterpillars feed on elm and the White-letter Hairstreak declined dramatically in the 1970s as a result of Dutch Elm disease.

For more than ten years, a group of Butterfly Conservation volunteers have been monitoring the butterfly and its gradual spread northwards.

The two dedicated volunteers, 70-year-old Ken Haydock and 69-year-old Jill Mills, found the White-letter Hairstreak eggs after being asked to check the elm trees at Paxton following last year’s butterfly sighting.

Ken, from Bolton, Greater Manchester, said: “It was a lovely sunny morning and we were searching the elm trees by the River Tweed at Lennel when Jill called me over. I could see by the look on her face that she had found something.

“We were both beaming with disbelief and delight when we realised what Jill had found and within seconds I was fumbling in my pack for the camera - my hands were shaking!”

Director of Butterfly Conservation Scotland, Paul Kirkland, said: “We will need a few more years of confirmed sightings before we can officially class this butterfly as a resident species in Scotland. It would take the number of butterflies found in Scotland to 34, which really would be something to celebrate.”