Butterfly populations in Scotland have increased, likely as a result of the warmer summers. The latest Scottish biodiversity indicator published by NatureScot examines the long-term trend for butterflies since 1979. While the overall trend shows a moderate increase, the picture is complex, with species evolving differently.
Some butterfly populations in the UK are moving further north in response to climate change. Those expanding their range north to southern Scotland include small skippers, Essex skippers, and most recently white letter hairstreak. Marigold, peacock and orange tip show a significant increase in population in the long term, while the small heather is also on the upswing. Meanwhile, speckled forests have expanded their range from their strongholds in the highlands and southeast Scotland to new areas.
Regular migrant butterflies such as the Red Admiral are also increasing over the long term in response to warming.
One of the species that will decline over the long term is the small tortoiseshell, which may be due to poor winter survival in warmer and wetter winters.
Grayling has also decreased, but the small mother-of-pearl moths and mother-of-pearl moths have increased significantly. Both of these species can benefit from native forest planting and targeted management in specific locations.
White-Letter Hairstreak, Copyright Peter Beesley, from the Surfbirds Galleries
Simon Foster, an analyst for NatureScot Trends and Indicators, said, “We know that habitat loss, climate change and urban development are key factors affecting butterfly populations.
“We are working with partners across Scotland on a number of projects to help our butterflies and other pollinators thrive, from creating and managing habitats to promoting wildlife-friendly gardening and best practice guidance for developers.
“Butterflies can also benefit greatly from more people getting involved in citizen science. If you want to help, why not join the butterfly monitoring program and take surveys? It’s easy, fun, and can help us improve our knowledge of what’s happening where, and give us the best chance of taking protective measures most effectively. “
To learn more, contact Butterfly Conservation Scotland: [email protected]