WARM summers are the likely cause of an increase in Scotland’s butterfly population – but there’s a mix picture across its species.
The latest Scottish Biodiversity Indicator published by NatureScot, the rebranded Scottish Natural Heritage, showed some species are moving northwards as our climate changes, including the small skipper, Essex skipper and white-letter hairstreak.
The government agency said ringlet, peacock, and orange-tip show significant long-term population increases, while the small heath is also on the up.
Speckled woods have expanded their range from their strongholds in Highland and south-east Scotland into other areas.
Regular migrant butterflies – such as the red admiral – are also increasing over the long-term as a response to climate change.
Species in long-term decline include the small tortoiseshell, which may be due to poorer overwinter survival in warmer and wetter winters, the agency said.
Grayling have also declined, but the small pearl-bordered fritillary and pearl-bordered fritillary have increased significantly, perhaps due to native woodland planting and targeted management at specific sites.
Simon Foster, NatureScot trends and indicators analyst, said: “We know that habitat loss, climate change and urban development are among the key factors that are affecting butterfly populations.
“We’re working with partners across Scotland on a range of projects to help our butterflies and other pollinators thrive, from habitat creation and management to promoting wildlife friendly gardening and best practice guidance for developers.”
He added: “Butterflies can also benefit greatly from more people getting involved in citizen science.
“If you would like to help why not join the Butterfly Monitoring Scheme and get involved with surveys?
“It’s easy, fun and can help us improve our knowledge of what is happening where, giving us the best chance of targeting conservation measures most effectively.”
Read more stories on Scottish Field’s wildlife pages.