Butterflies bounce back from weather extremes

Just Regional
Mar 8, 2024 3 mins read

Butterflies are fragile-looking flutterers that brighten our natural world, but they are tougher than we might think.
Volunteer butterfly fans have helped survey the numbers of species across Norfolk in two nationwide surveys.
Some are showing declines, while others have soared in numbers. And, overall, they fared better in 2023 than experts feared amid extreme heat and wet weather.
But while the resilient creatures ride the peaks and troughs of changing climate and habitat alone, one man-made intervention near Aylsham has also helped one species “move house” to boost numbers in a new country park.
The summertime switch saw Silver-Studded Blues caught at Buxton Heath and moved to Broadland Country Park near Drayton.
Butterfly Conservation Norfolk branch co-chairman Alan Dawson said: “We helped the Norfolk and Norwich Naturalists Society, armed with butterfly nets. We caught about 20 females and 10 miles, popped them into pots in a cool bag and took them to the park. I am really looking forward to see what shows up on the next survey there.”

ON THE MOVE: Dave Weaver, Alan Dawson and Mark Collins help translocate Silver-Studded Blues Pictures: HANS WATSON

One survey, the Wider Countryside Scheme which gathers information from random location walks undertaken once a month over the peak butterfly flight season, showed an 80pc increase in butterfly numbers.
The other one, the UK Butterfly Monitoring Scheme Transect counts which take sightings from 26 weekly surveys mostly on managed nature sites over 26 weeks, showed a lower 9pc rise, but was still encouraging.
More than half the species recording increases. The Brown Argus had an exceptional year showing a 400pc increase. There was a rise in Meadow Browns on grassland and more little Holly Blues in people’s gardens.
But there were some worrying declines – including the Small Tortoiseshell, but Alan hoped they would bounce back through migration from Holland as had happened in the past. The Ringlet has also shown a year-on-year decline with the number dropping each year from 1161 in 2019 to 250 in 2023.
Another worry is a 40pc dip in Swallowtails, the nation’s biggest butterfly and found almost exclusively on the Norfolk Broads including Sutton Fen, Hickling and How Hill.
Alan added: “Despite a positive 2023 overall, historically populations for our butterflies remain low. “The good news is where conservation action is carefully targeted and sustained in the long-term it has real impact. Butterfly Conservation continues to work in partnership with other organisations, communities and landowners, on many projects that are halting declines and turning butterfly numbers around right across the country.
“Butterflies are tougher than a lot people give credit for. Look at the Painted Ladies who fly here all the way from North Africa!”
Butterfly Conservation Norfolk will continue to monitor data in 2024, including what effect the mild but very wet winter had on populations.
<blob> The charity is keen to recruit more volunteers to help with its work. Find out more at www.butterfly-conservation.org/in-your-area/norfolk-branch 

Silver Studded Blue

FALLING NUMBERS: The iconic Swallowtail has taken a 40pc dip in numbers. Picture: MALCOLM FISHER

CONCERNS: The Small Tortoiseshell is one of the butterflies showing a worrying decline. Picture: MICHELLE WALKING

HOPE: The Brown Argus has enjoyed an exceptional year. Picture: BOB EADE

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