Warm weather has led to “an explosion” of exotic butterflies across the UK this summer in a “once-in-a-decade phenomenon”.
Clouds of butterflies have been pictured fluttering across the country because of the warm spring, leading to a Painted Lady Summer.
Butterfly Conservation called it a “once-in-a-decade phenomenon”.
Professor Richard Fox, Butterfly Conservation’s head of science, said: “The inter-continental migration of Painted Lady butterflies is a wonder of the natural world and one of the longest insect journeys on the planet.
“The numbers we’re seeing here at the moment have already dwarfed the total number of Painted Ladies we saw last year, and we’re absolutely delighted.
“With their beautiful pinky-orange, black and white patterned wings, they are one of our most popular species. The new generation of Painted Ladies is emerging across the UK right now prior to flying the next leg of the species’ epic journey, and helping to count them is a great excuse to take part in this year’s Big Butterfly Count.”
The wildlife charity has asked people to report how many they see as part of its yearly survey.
People around the UK reported a total of 15,856 Painted Ladies last year.
The last time the UK had a Painted Lady Summer in 2019, the total was more than 420,000.
The Painted Lady is a long-distance migrant that visits the UK each year, feeding on flowers like buddleia.
Kate Merry, Butterfly Conservation’s head of engagement, said: “This is a very exciting and unexpected twist to this year’s Big Butterfly Count: it’s astonishing that such a seemingly delicate insect can accomplish this incredible long-distance journey.
“We’ve already seen absolutely loads of them across the UK, so we are very excited to see how many people report them and where.”
This year’s Big Butterfly Count runs from July 17 to August 9.