Are we losing our butterflies?
- Rhiannon Irving
- Aug 7
- 4 min read
Taking a minute to stop and watch a butterfly fluttering gracefully yet almost haphazardly amongst the green trees and colourful wildflowers must surely be one of the most peaceful moments in nature that a person could have. I am lucky enough that in the relatively suburban environment in which we live, there are fragments of green spaces dotted around our house in which we see butterflies daily. To me, they are a reminder that biodiversity and nature, in the form of these beautiful and iconic species, is still persevering as urban environments encroach on our green spaces.
"Beautiful and graceful, varied and enchanting, small but approachable, butterflies lead you to the sunny side of life. And everyone deserves a little sunshine" Jeffrey glassberg, biologist and author
However, I am clearly a victim of 'shifting baseline syndrome', which is the change in our perception of what normal is, such as me considering the number of butterflies I see to be high when historically it is not. All of the species I have photographed are least concern species according to the IUCN Red list. I have not seen, on my local walks, a single vulnerable or endangered species. That in itself shows me that my perception is likely to be inaccurate.
What are the long term trends?
80% of butterflies have declined in either abundance or distribution from 1970 to 2019, a figure given by the State of the UKs Butterflies 2022 report. It’s an extremely worrying number and populations are threatened by a multitude of factors. The most pervasive threat is habitat loss, caused by activities such as agriculture and urban development for housing. These activities directly remove butterfly habitat, for example, changing unmanaged grasslands into managed arable farmland, or building over woodland and wetlands. It also fragments it, with small patches of habitat intersected by roads and developments, making it harder for the butterflies to distribute into new areas and breed.
According to the 2022 report, habitat specialist species (such as the Northern Brown Angus and Pearl-bordered Fritillary) that are reliant on very specific habitat and environments have, on average, decreased in abundance by 27%, and in distribution by a huge 68%. Even wider countryside species that are 'generalists' (surviving and breeding in a range of urban, suburban and rural environments) have, on average, decreased in abundance by 17% and distribution by 8%. Examples of these generalist species that have decreased in both distribution and abundance are the Small skipper (left above) and Ringlet (right above.) Peacock butterflies (left below) and Gatekeepers (right below) also decreased in abundance.
What about the past two years?
In 2024, the Big Butterfly Count, run by Butterfly Conservation, had the worst year on record for butterfly numbers. Summer 2024 was cloudy and wet for the most part, and butterflies struggle to thrive in these conditions. This is thought to be a key factor in the low numbers. Data from the UK Butterfly Monitoring Scheme (UKBMS) in 2024 showed that 31 of the 59 UK species declined between 2023 to 2024. Given the poor weather conditions, it is hopefully just an annual fluctuation of numbers (like happens to populations of all species) and not a new normal.
So far in 2025, the UK has had the driest March, April and May since 1893 (you read that right!), and several early heatwaves, and there have been observed increases in butterfly numbers under the sunshine. Butterflies are ectotherms (cannot produce their own body heat and therefore rely on the sun's warmth) and 18 species have been observed 2 weeks early this year, and 24 species a week early. It is hoped that the Big Butterfly Count 2025 will show an increase in numbers from 2024 to reflect the hopefully positive effect of the change in conditions.
There is hope..
Hope is not lost though, despite the same pattern of declines across so many species. 26% of UK species have increased significantly in abundance and 14% have seen an increase in distribution, including two of the UK priority species.
In June this year, a count found that numbers of the rare Heath Fritillary have risen from 600 in 2024 to 1000 in a National Trust estate in Exmoor National Park, Somerset. In the 1980s, this species was almost extinct. The species has very specific habitat requirements, and collaboration between Butterfly Conservation and National Trust has controlled bracken, supported conservation grazing and the management of specific plants. This location is now considered the most important area for the Heath Fritillary, as well as three other sites across the UK.
In May, the Small Blue butterfly has seen numbers double on an estate in Scotland, again supported by Butterfly Conservation to manage and maintain habitat. The caterpillars of this species only eat kidney vetch and the conservationists have been improving an area along the coast to clear vegetation and create more space for planting the vetch.
The Chequered Skipper went extinct in 1976, but is now breeding again in Northamptonshire after being reintroduced from Belgium in 2019. Plots of sunny wildflower-rich areas were carefully planned and managed and in 2024 there were over 350 butterflies counted in Fineshade Wood where they were originally released. There have been some sightings in other areas, so the project hopes that the species are increasing their distribution.
These three species are some of the examples of successful conservation projects. However, habitat loss that is driving the declines is increasingly pervasively and conservation work is always playing catch-up. The declining population trends of so many species can be reversed but this requires a huge amount of work and dedication to plan, manage and maintain the habitats that are needed. It is not an easy fix. But with the help and dedication of charities such as Butterfly Conservation, local and national organisations, landowners and even the general public, there is a future in which populations of butterflies can increase, survive and thrive.
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