The warm spring weather of 2014 boosted the number of some butterflies, including the UK’s rarest and endangered High Brown Fritillary, a survey has revealed.
The critically endangered High Brown Fritillary also benefited from schemes to restore habitat, said Butterfly Conservation. It experienced its best season in 2014 for 10 years with numbers increasing by more than 180 per cent compared to 2013.
But others struggled in high summer, such as the cabbage white.
Known for its black and striking orange wings and swift flight, the High Brown Fritillary was once widespread across England and Wales but habitat loss has resulted in alarming declines raising fears that it could be heading toward extinction in the UK.
The survey found the High Brown Fritillary, one of only two critically endangered butterflies in the UK, recorded its best year for a decade.
Statement from UK Butterfly Monitoring Scheme led by Butterfly Conservation and the Centre for Ecology and Hydrology, this was due to the warm spring weather which was good for emerging caterpillars and work to restore its habitat.
Dr. Tom Brereton said, the butterfly was on the road recovery but there was still a long way to go before the long-term decline has been reversed.
He is the head of monitoring of Butterfly Conservation.
“The High Brown Fritillary is one of only two butterflies classed as critically endangered in the UK so it is fantastic news that numbers are at their highest level for more than a decade.
“A huge amount of work co-ordinated by Butterfly Conservation has been put into conserving this butterfly in recent years, especially though wildlife-friendly farming schemes, so the results will come as a welcome boost to all involved.
The High Brown Fritillary can only be found on around 30 sites in the UK, where Butterfly Conservation is working with landowners to restore suitable habitats.
It breeds in fairly dense bracken stands on moorland slopes where violets occur and such sites need extensive grazing by cattle or ponies, together with regular scrub management.
Butterfly monitoring results for 2014 – top five winners and losers
Winners % change from 2013-2014
- Red Admiral 189
- High Brown Fritillary 181
- Black Hairstreak 172
- Large Skipper 86
- Large Heath 72
- Large White -69
- Small White -66
- Adonis Blue -56
- Chalk Hill Blue -55
- Purple Hairstreak -50
Since 1976, UKBMS involves thousands of volunteers collecting data through the summer from around 2,250 sites across the UK.