Members of the public are being urged to take part in the UK's largest-ever butterfly count, starting this weekend, to help provide valuable information on the fast-disappearing species and halt further decline.
The Big Butterfly Count, backed by the largest insect conservation charity in Europe, Butterfly Conservation and retailer Marks & Spencer, aims to be the biggest exercise ever to assess how well the British countrysidecan support these species. Organisers plan to make the event annual..
Adults and children are being encouraged to make a 15-minute count during Save Our Butterflies Week, which runs from 24 July to 1 August. Counts can be made anywhere – from parks and gardens, to fields and forest and city centres as well as the countryside.
Butterflies and moths are sensitive to environmental change, which makes them a good indicator of the state of the countryside. They are essential for the pollination of plants, and caterpillars provide food for many birds and other wildlife.
But in the last three years, butterflies in the UK have suffered the most dramatic decline in numbers since records began, with almost half of them under threat as their habitats have been destroyed. Five native species of butterfly are extinct – including the large tortoiseshell, which died out in the 1980s, and the black-veined white, which disappeared in the 1920s. The situation for moths is even worse, with over 60 species extinct.
Nature reserves are typically the only places that regularly monitor butterfly movement. The last time a national count was carried out was in 2002. This was funded by a small grant from the National Lottery, and saw 10,000 people take part. This year the charity is aiming for at least 100,000 participants. M&S will be rewarding those who join in with a 10% discount off M&S plants, and discounted membership to Butterfly Conservation.
Sir David Attenborough, president of Butterfly Conservation, said: "The Big Butterfly Count should be great fun. Butterflies are extraordinary, heart-lifting creatures – visions of beauty and visions of summer. Butterflies in profusion tell us all is well with nature. When they decline, it's a warning that other wildlife will be soon be heading the same way.
"So with the big butterfly count we will be doing more than just counting butterflies – we'll be taking the pulse of nature."
With July's warm weather boosting numbers of woodland butterfly species, this year experts have also spotted some unusual colour variations which would have been the highlight of old-fashioned butterfly collections. Matthew Oates, conservation adviser at the National Trust, managed to photograph a purple emperor butterfly with markings so rare he said it would only be seen "once in a purple moon - which is rarer than a blue moon".
• For more information about the count, visit bigbutterflycount.org.
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