Overview

• The Big Butterfly Count runs from July 18 to August 10 and invites volunteers to spend 15 minutes recording butterflies via a free app or website.
• Naturalists report an “outstanding” summer marked by unusually early adult emergences and northward sightings of species such as the purple emperor and white-letter hairstreak.
• Experts warn that growing drought conditions across Britain threaten caterpillar food plants and could undermine next year’s butterfly generation.
• Despite favorable weather for adults, vulnerable species including the rare large blue, ringlet and small tortoiseshell continue to show declines.
• Data from up to 100,000 citizen scientists each summer help inform conservation strategies and monitor long-term trends against a backdrop of habitat loss, climate change and pesticide impacts.