Science

Declining Trend For Our Butterflies

Image credit Rosie Hopkins

Wildlife charity Butterfly Conservation has released data on the number of butterflies and some day-flying moths recorded across the UK during this year’s Big Butterfly Count, which ran from 15th July – 7th August.

Results for Scotland

The top five butterfly species encountered in Scotland were Small White, Meadow Brown, Large White, Ringlet and Peacock.

Another winner for the 2022 Count was the Comma, which saw an increase of 187% in Scotland compared with last year. This species has a flexible lifecycle which enables it to capitalise on favourable weather conditions, which could account for its particular success this year. The Comma only recolonised Scotland in the early 2000s (having been absent for about130 years) but has expanded its range rapidly since then.

Comma Image credit: Mike McKenzie, Butterfly Conservation

Peacock, Red Admiral and Small Tortoiseshell also all seem to have fared well in Scotland this summer and bucked the UK trend of decline. This is welcome news as all three species showed declines in Scotland last year. 

Image credit: Noel Donaldson

However, overall, the trend for butterflies across Scotland remains a concerning one, with the results of the Big Butterfly Count 2022 showing an average of just under seven butterflies seen per Count. While this is a slight increase on last year, it still remains low compared with many previous years in the 13-year history of the citizen science project.

Neither of the two species of blue butterfly included in the Big Butterfly Count, the Holly Blue and the Common Blue, did well in Scotland this year, despite significant increases in other parts of the UK, with a decline of 35% for the Holly Blue and 13% for Common Blue.

The Scotch Argus was added to the species list for the Big Butterfly Count in Scotland for the first time last year. Unfortunately it wasn’t good news for the species, which declined 38% on 2021 levels.

A total of 3,633 Butterfly Counts were carried out in Scotland during the event while, across the UK as a whole, participants spent a combined total of over two and a half years counting butterflies in their gardens, local parks and in the countryside.

The UK Results

The Gatekeeper, a species often found along hedgerows and woodland rides, as well as in gardens, in the southern half of Britain, was the most spotted butterfly during this year’s Big Butterfly Count. This is welcome news, as the Gatekeeper experienced its second worst Big Butterfly Count result in summer 2021, and it’s the first time since 2017 that this species has had the top spot overall.

It was good news for the blues as well – with both the Common Blue and the Holly Blue species faring well in the 2022 Big Butterfly Count. Having had their worst results in 2021, these species bounced back, with the numbers reported increasing by 154% for the Common Blue and 120% for the Holly Blue.

Another winner for the 2022 Count was the Comma, a popular species often found in gardens, that saw an increase of 95% compared with last year. The Comma has been making a slow comeback from its low point in the 1910s and expanding its range rapidly northwards.

An increase in range – a result of climate change – accounts for many of the sightings of these species in the north of the UK. The Holly Blue butterfly, for example, had only occasionally been recorded in Scotland prior to the 2000s, but after becoming firmly established in Edinburgh from 2006 and in Ayr from 2008 the species has subsequently spread across swathes of Scotland.

Overall, the trend for butterflies across the UK remains a declining one, with the results of the Big Butterfly Count 2022 showing an average of just under 9 butterflies seen per Count, which is once again an all-time low in the thirteen years since the citizen science project began.

Species that saw a worrying decline from last year include some well-known favourites, such as Red Admiral, Small White and Meadow Brown.

Head of Science for Butterfly Conservation, Dr Richard Fox, said:

“We might have expected this summer to have been a much better one for butterflies given the good weather we experienced in many parts of the UK. The fact that more butterflies weren’t seen is concerning and it’s clear that much more needs to be done to protect and restore habitats to aid nature recovery. The sun could shine for days on end, but we still won’t see more butterflies unless there is habitat for them to thrive in.”

Almost 100,000 Butterfly Counts were carried out during the event, with participants spending a combined total of over two and a half years counting butterflies in their gardens, local parks and in the countryside.

Dr Zoe Randle, Senior Surveys Officer at Butterfly Conservation, said:

“The vast majority of Big Butterfly Counts are done in gardens, which makes this data especially valuable because this type of habitat is under-represented in many of our other schemes.

“We can create habitat for butterflies such as the Holly Blue and Comma in our gardens, by cultivating Holly and flowering Ivy for the former and growing Hop, elms and nettles for the latter. Gardens that are wildlife friendly can provide vital habitat for these insects, allowing them space to feed, breed and shelter.”

The UK Results

 Big Butterfly Count 2022UKAbundanceAve per count% change from 2021
1Gatekeeper142,6181.5858.6%
2Large White139,6661.55-9.4%
3Small White125,8391.39-25.8%
4Meadow Brown109,3101.21-17.5%
5Red Admiral10,5470.45-20%
6Peacock39,1990.43-5.5%
7Small Tortoiseshell29,2880.3213%
8Comma27,9160.3194.7%
9Ringlet26,1930.29-38.5%
10Common Blue24,5920.27154.4%
11Speckled Wood24,0130.2797.4%
12Green-veined White17,1620.19-8.1%
13Holly Blue14,8090.16119.8%
14Small Copper12,4920.14-18.9%
15Six-spot Burnet8,6070.10-19.8%
16Painted Lady8,2880.091.2%
17Brimstone7,3210.0836.4%
18Marbled White5,5210.06-71.4%
19Jersey Tiger3,2350.04136.5%
20Silver Y1,4930.02-39.4%
21Scotch Argus9980.01-36.2%
 TOTAL809,1078.95-2.8%

The Big Butterfly Count is the largest citizen-science project of its kind and relies on volunteers spending 15 minutes outside each summer, counting the number and type of butterflies they see. Taking part each year helps scientists to gather important data on how butterflies and moths are coping with changing climate, changing weather, and habitat loss.

Next year’s Big Butterfly Count will take place from Friday 14th July – Sunday 6th August 2023.

To find out more visit www.butterfly-conservation.org