Butterfly Boom Amid UK's Hottest Summer on Record

According to the latest reports, the UK has just experienced its hottest summer on record in 2025, following the sunniest-ever spring the previous year. This provided excellent conditions for the country's butterfly populations, as evidenced by the record-breaking participation in the annual Big Butterfly Count.

More than 125,000 members of the public submitted sightings to the count, which was launched in mid-July and ran until early August. The most numerous species spotted were the large white, small white, gatekeeper, red admiral, and meadow brown. Notably, the small white butterfly recorded its best-ever year, despite suffering a record low in 2024 due to a wet spring and cool summer.

However, the news is not entirely positive for all butterfly species. The small tortoiseshell, which had its worst count in 2024, recorded a below-average year in 2025 and has declined by a staggering 60% since 2011, according to the East Lulworth-based charity behind the count. The overall figure of 10.3 butterflies seen per 15 minutes was "only broadly average by modern standards and has done little to reverse longer-term declines."

Experts warn that urgent action is still needed to support butterfly populations, including improving their habitats, restoring environments, and reducing pesticide use. Without such measures, they say, a true recovery in butterfly numbers is unlikely, regardless of how favorable the weather conditions may be.