Posted 27th Jun 2018
The Clouded Yellow is a migrant butterfly that arrives from May onwards
Usually, only small numbers will turn up, but some years, there will be mass migrations. Preferring open habitats (in particular chalk grassland), the medium-sized, golden-yellow butterfly will fly here from North Africa and southern Europe. Small in numbers most years, they will occasionally turn up en masse (these are remembered as 'Clouded Yellow Years').
Adults can arrive at any time during the spring and summer and can be found in a variety of open habitats, although, in southern England, they are especially fond of chalk grassland.
Foodplants of the caterpillars include wild and cultivated clovers along with Common Bird's-foot Trefoil.
With a bright yellowy-orange upperwing surface, lined with broad, dark edges and a yellowy-green underside, it rests with its wings closed; two-silver white spots can also be seen on the hindwings when it's in this pose.
While it can turn up anywhere, it's more frequently spotted in southern England.
While they are unable to survive UK winters, Clouded Yellows could be becoming more common, or perhaps even residents, if temperatures rise due to climate change.
Text and information courtesy of The Wildlife Trusts / image courtesy of Margaret Holland