IT NOW requires “major expeditions” to find some once-common butterflies as changes to the countryside have affected species in the past half century, an expert has warned.
The National Trust’s Matthew Oates, who is celebrating his 50th butterfly season, said the creatures had been hit by urban sprawl, intensive farming and forestry, a changing climate and diseases affecting plants and animals.
And the future is likely to see more changes as some species are forced to adapt to climate change while others colonise a warmer UK.
Although some butterflies have done well since the 1960s and a number have even colonised new areas, the losers have outweighed the winners, Mr Oates said.
“Some of the species I was most familiar with and took for granted are now major expeditions to go and see, and that’s significant,” he said.
One of these is the wall brown, which used to be common along road verges, woodland rides and rough grassland, but started to disappear in the mid 1980s for reasons experts do not really understand, and is now rare away from the coasts.
Other species found in woodland clearings, such as the pearl-bordered fritillary and the Duke of Burgundy butterflies, are also struggling, while the small heath, one of the UK’s commonest butterflies, has virtually disappeared from woods, although it is still found on grassland.
The white-letter hairstreak, which breeds on elms, collapsed as a result of Dutch elm disease, and although it has made a comeback, it is only a shadow of its former self.
However, there have been some winners over the past 50 years too, in particular species which have been helped by conservation efforts. The large blue was reintroduced in the UK from Sweden and the Adonis blue and and silver-spotted skipper are making a comeback after being in “dire straits”.