A butterfly that disappeared from Scotland 150 years ago has enjoyed its best year on record since its return north of the border.
The comma butterfly was lost to Scotland as it retreated in range in the 1870s but returned around 25 years ago due to the effects of climate change.
The species, described by Sir David Attenborough as “one of our most exquisite butterflies”, crossed from England around 2000 and has been gradually recolonising northwards, reaching the northernmost tip of mainland Scotland around five years ago.
Counts this summer revealed the species had increased by 558% in abundance in 2025 compared with the previous summer, with numbers 75% up on the previous record high set in 2023.
Dr Richard Fox, Head of Science at the wildlife charity Butterfly Conservation, said: “Summer 2025 was the best yet for the comma butterfly in Scotland since our counts began.
“The species was lost to Scotland around 150 years ago. It began spreading northwards in Britain by the 1970s and recolonised Scotland around the turn of this century.
“It’s not a butterfly you usually see in large numbers but it is very distinctive because of the scalloped edge to its wing that none of our other butterflies have. It’s a lovely thing to see.”
The species, Polygonia c-album, takes its name from a white comma-shaped marking on its underside.
With its wings closed, the orange and brown-coloured butterfly is camouflaged against dead leaves, while the larvae, flecked with brown and white markings, resemble bird droppings.
Scientists believe the comma’s success is due to a combination of climate change and the butterfly’s increased use of nettles as a caterpillar food plant.
While other butterflies have spread from England into Scotland, the comma is among the most dramatic examples, moving north at around 11km per year after crossing the border.
Because they hibernate as adult butterflies they are often among the first butterflies to be seen each year.
Dr Fox said: “Butterflies are a very visible sign of climate change. We hear about trends in increasing temperatures but it can be hard to see tangible signs that change is happening.
“When you see a butterfly you’ve never seen before in your area that is a response to climate change.”
