Butterfly species fail to surge despite hot summer

The common blue butterfly had its third worst result in the 15-year count

Some butterfly species failed to thrive in the UK's hot summer after historical low numbers in 2024, a charity has said.

The small white, large white and Jersey tiger moth were seen in record numbers in 2025, according to Butterfly Conservation.

However, the holly blue, common blue and meadow brown had a poor year according to the charity's Big Butterfly Count, which recorded sightings by volunteers in July and August.

The Dorset charity urged retailers to help end the "butterfly emergency" by removing synthetic pesticides from sale.

Head of science Dr Richard Fox said: "Many of our common butterfly species are facing significant pressure from challenges linked to habitat loss, climate change and pesticide use.

"We know the weather impacts their numbers and with the summer we've just had we should be seeing them in far greater numbers."

The UK summer was the hottest on record, following the sunniest-ever spring, which the charity said provided good conditions.

The meadow brown was commonly seen but had a relatively poor year, the charity said

More than 125,000 members of the public submitted sightings to the Big Butterfly Count, which was launched in Winchester, Hampshire, on 18 July and ran until 10 August.

The most numerous species were the large white, small white, gatekeeper, red admiral and meadow brown.

The small white recorded its best-ever year despite a record low in 2024, which had a wet spring and cool summer.

However, the small tortoiseshell, which had its worst count in 2024, recorded a below-average year and has declined by 60% since 2011, according to the East Lulworth-based charity.

It said this year's 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".

Dr Fox said trends over 15 years showed more than twice as many widespread species had declined significantly compared with those that had increased in number.

He said: "There remains a need for us to take urgent action to support our butterfly populations, including improving the environment in which they live, restoring habitats and reducing pesticide use.

"Until we do these things we are unlikely to see a great recovery in butterfly numbers, regardless of how much the sun shines."