Butterfly Conservation has launched the 2026 Big Butterfly Count, urging the public to help determine if the UK is heading for a bumper butterfly season—or even a “painted lady summer.” The charity noted that one of the warmest springs on record has created ideal conditions for butterfly breeding and caterpillar growth, raising hopes for strong numbers this summer.
Warm Spring Boosts Butterfly Prospects
According to the charity, heatwaves, warm dry spells, and occasional heavy rain have fostered excellent conditions for butterflies. Small coppers and holly blues have already been spotted in large numbers, while peacock, red admiral, and brimstone butterflies have had a promising start to the year. There are also signs of a possible “painted lady summer,” when the migrant butterfly arrives in the UK in large numbers, but the charity needs widespread public sightings to confirm this.
Annual Citizen Science Survey
The Big Butterfly Count runs from July 17 to August 9 and is the world’s largest citizen science project focused on butterflies. Participants simply spend 15 minutes in a sunny outdoor spot—such as a garden, park, or local countryside—and report their sightings via the free Big Butterfly Count app or website (bigbutterflycount.org). The data helps scientists track how common butterflies and day-flying moths are faring, and how they are responding to climate change and habitat loss.
Reversal from 2024’s ‘Butterfly Emergency’
The hopeful outlook marks a sharp contrast to 2024, when the count yielded the worst results in the scheme’s history, prompting Butterfly Conservation to declare a “butterfly emergency.” A hot, dry, and sunny 2025 boosted many species, and the warm spring of 2026 could continue that trend. However, the charity warns that long-term declines remain a serious concern.
Long-Term Declines Continue
Butterfly Conservation reports that 80% of butterfly species have declined over the past 50 years due to habitat loss, pollution, and climate change. Kate Merry, the charity’s head of engagement, said: “After the colourful spring with seemingly lots of beautiful butterflies appearing across the UK, it’s tempting to assume we’re heading for a bumper summer, and we’d love nothing more as most of our butterfly species have undergone long-term declines. But a bright spring is only ever part of the story, which is why we need people out there taking part in the Big Butterfly Count this summer.”
Why Butterfly Counts Matter
Merry emphasized that butterflies are key indicators of biodiversity and environmental health. “Every single person that takes part in the Big Butterfly Count and submits their sightings is helping us to see how these pollinators are doing, which in turn helps conservationists build a wider picture of how all insects are faring,” she said. The charity hopes that widespread public participation will provide the data needed to assess whether 2026 truly delivers a bumper butterfly summer.
