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Red admiral butterfly sightings at their highest UK level since 2010 Red admiral thrives in butterfly count while whites show decline
(about 9 hours later)
The number of red admirals in Britain soared over the summer despite the soggy conditions, according to conservationists who said public sightings of the butterflies had risen to their highest since 2010. Summer’s washout failed to dampen the prospects for the red admiral, one of the UK’s most popular butterflies, whose numbers rose by 75% compared with last year, according to the annual Big Butterfly Count.
Results from the Big Butterfly Count show that sightings of red admirals reached 73,000 over the three-week survey, a rise of 75% on 2016, and as many as were counted in the past three years put together. Other butterfly species were less fortunate, however, with declines seen across the three common species of white butterflies. The green-veined white and both the large white and small white were down more than a third on last year, reflecting difficult weather conditions.
The butterflies benefited from the mild winter and warm spring after a good year in 2016, according to Butterfly Conservation, the charity behind the survey. The boom in red admirals saw them come second in the rankings of most commonly seen butterflies in Britain, behind gatekeepers, whose sightings were up 24% on last year to more than 93,000. The red admiral is one of the best recognised butterflies in Britain thanks to its distinctive black, orange and white markings. More than 73,000 were counted in this year’s census carried out by the Butterfly Conservation charity between 14 July and 6 August. The large showing came on the back of a bumper year last year, and a mild winter and spring that helped some of the species stay in the UK – a new development in recent years, possibly assisted by a warming climate, for what used to be a summer visitor from southern Europe.
Other common butterflies also fared well over the summer, with sightings of commas rising 90% and small coppers up 62% on 2016. Compared to last summer’s count, the number of common blues rose 109%. The red admiral was not the most numerous butterfly in the count. The gatekeeper, also known as the hedge brown, with orange and brown wings and prominent black spots, was seen more than 93,000 times, up nearly a quarter on last year.
The weather during the winter and spring led many species to emerge earlier than usual, meaning some butterfly species peaked before the count started. The wet weather in the summer further reduced the number of butterflies spotted in the survey. This year’s wet summer, the 11th wettest on record (though temperatures were above average), spelled poor conditions for butterflies, which thrive in warmer and sunnier summers. Last year was also a bad year for butterflies and moths, so improvements this year are relative in many cases.
Several species were seen far less than last year, with all three of the UK’s common white butterfly species down. Numbers of green-veined whites were at their lowest since the count began in 2010, with sightings of the other two species at their second-lowest. On average, volunteers spotted only 11 butterflies each during the count, the worst figure recorded by the charity. It was a bumper year for the count itself as a record 60,000 people took part in the three-week census which is the world’s biggest survey of butterfly numbers. More than 550,000 butterflies were recorded, but the record number of surveyors hides a more concerning picture: each participant saw on average only about 11 butterflies, the lowest number per person since the count began in 2010.
“It hasn’t been a vintage summer for butterflies, but there have been some real positives,” Richard Fox, head of recording at Butterfly Conservation, said. “The flurry of red admirals on buddleia bushes, vivid golden commas holding territories along the hedgerows and beautiful flecks of blue and orange among the long grass as common blues and small coppers made the most of the sunshine before the next shower.” Richard Fox, head of recording at Butterfly Conservation, said: “It hasn’t been a vintage summer for butterflies, but there have been some real positives. The highlight has been the huge number of people that have got involved, spent time enjoying and counting our native butterflies and moths, and done something useful and important in the face of so much wildlife decline.”
More than three-quarters of the UK’s butterflies have declined in the past 40 years, with some common species, such as the small tortoiseshell, experiencing a dramatic fall in numbers. The other most numerous butterflies spotted by volunteers were the meadow brown, whose numbers were third highest, the peacock with nearly 30,000 examples, the common blue with nearly 20,000, and the speckled wood butterfly at more than 18,500.
While red admirals are now a common sight in British gardens, the butterflies were strictly summer visitors a few decades ago. The butterflies arrived in the spring and summer from the warmer parts of Europe, and bred in the UK before returning south with their offspring for the winter. The butterflies still migrate, but many now overwinter in Britain, making red admirals the most commonly seen butterfly in the winter months. Despite the good news for the red admiral, butterflies in the UK are under threat, both from a changing climate, with the last 10 years showing a pattern of damper summers, and from human factors. Butterflies are losing their habitat as a result of intensive farming, pesticides, urbanisation and populations becoming cut off, and the added pressure of weather changes is having an impact on their breeding and food sources.
Butterflies and moths are also valuable to farmers and gardeners as pollinators, though on a smaller scale than bees.