Britain’s butterflies bounce back in annual count – but only to average levels

Biggest insect survey in world finds UK’s hot summer led to increase in numbers of many species, but overall trends are still concerning

• Top 10 most-sighted butterflies in 2025’s Big Butterfly Count – in pictures

Butterfly numbers have bounced back after the dismal summer of 2024, but the hottest summer on record delivered only an average number of the insects in the annual Big Butterfly Count.

More than 125,000 citizen scientists joined the biggest insect survey in the world this summer, counting an average of 10.3 butterflies in each 15-minute count in parks, gardens and green spaces across Britain.