An increasing number of moth species are arriving and settling in Scotland as a result of climate change, experts have revealed.
Almost 30 new species of pyralid moth have been recorded in the UK in the last 30 years, with eight becoming established residents.
While most have settled on the south coast, several pyralid moth species from England have now made their home north of the Border.
The Thistle Ermine has gradually colonised large swathes of Scotland since it first arrived in 2002. Other species including the Gold Triangle and Hypsopygia glaucinalis have also been seen for the first time in Scotland.
The wildlife charity Butterfly Conservation said that pyralid moths include some of the largest and most distinctive of the 1,600 species of micro-moths found in the UK.
The North Sea and English Channel provide natural barriers to many potential colonising species, but the horticultural trade has offered one route into the UK with moth eggs, caterpillars and even pupae hitching a ride on imported plants. Climate change has also altered conditions, enabling moths to take advantage of habitats in new areas including Scotland.
Pyralids are often under-recorded so scientists need new records of sightings to determine how these moths are faring across the UK and to spot any new species that have arrived.
As part of the annual Moth Night survey – an annual UK-wide event that spans three days and nights from today – Butterfly Conservation, along with moth and butterfly journal Atropos and the Centre for Ecology and Hydrology, want people to look for pyralid moths in their gardens, in the countryside and at specially organised moth trapping events.
Richard Fox, Butterfly Conservation’s associate director of recording, said: “There are several moth species new to Scotland in the last 30 years, many of which have spread up from England.
“The Thistle Ermine, which is bright white with black spots, started to be seen in Scotland around 2002 and has gradually spread out, colonising southern and central Scotland. Its caterpillars feed on thistles, so it’s ideal for Scotland.
“Another new species to Scotland is the Gold Triangle, which now occurs in gardens, farmland and woodlands right up to Argyll. It’s a very pretty thing, purple with gold spots and a gold border.”
The recent increase in new species being recorded comes as many of the UK’s moths are in decline as a result of habitat loss and agricultural intensification.