Despite the warm and sunny spell leading to an increase in the appearance of certain butterfly species in summer, butterfly numbers remain “concerningly low”.
Sightings of the popular garden species comma have increased by 95% compared to last year, according to annual survey results big butterfly count in England.
Gatekeepers, a species often found in hedges and woodland rides as well as gardens, were the most spotted butterflies in this year’s tally, with reported numbers up 58 percent from last year.
However, experts fear butterfly and moth numbers in the UK are still falling, with wildlife charity Butterfly Conservation describing the figures as “concerningly low”.
Dr Richard Fox, head of butterfly conservation science, said: “Given the good weather we’ve experienced in many parts of the UK, we might expect this summer to be much better for butterflies.
“The fact that more butterflies are not being seen is concerning and it is clear that more needs to be done to protect and restore habitat to help nature recover.
“The sun can last for days, but we still won’t see more butterflies unless there is habitat for them to thrive.”
Read more: Britain’s bizarre and wonderful woodland nature, including penis ‘stinky horns’
With nearly 100,000 butterfly counts conducted between July 15 and August 7, citizen scientists spent a total of two and a half years counting different species in their gardens, local parks and countryside.
The results showed an average of fewer than nine butterflies per count, which conservationists say is an all-time low in the 13 years since the project began.
However, some species saw increases, including common blue and holly blue, which increased by 154% and 120%, respectively.
Experts say Holly Blue was only occasionally recorded in Scotland until the 2000s, but after gaining a foothold in Edinburgh in 2006 and Ayr in 2008, the species then spread across large swathes of Scotland.
The comma also slowly recovered from its lows in the 1910s and rapidly expanded its range northwest, the team added.
Dr Zoe Randall, Butterfly Conservation Senior Inspector, said: “The vast majority of large butterfly counts are done in gardens, which makes these data particularly valuable as this type of habitat is found in many of our other programmes. Underrepresented.
“We can create habitats in our gardens for butterflies (like holly blue and comma) by planting holly and flowering ivy for the former and hops, elm and nettle for the latter.
“Wildlife-friendly gardens can provide important habitat for these insects, giving them space to forage, reproduce and shelter.”
One of the largest citizen science projects of its kind, Big Butterfly Count helps scientists gather vital data on how butterflies and moths are responding to climate change and habitat loss.
Next year’s statistics will be held from July 14th to August 6th.