Photo above left by Tim Furness

Photo above right by Emma Walters

Other photos by Martin Partridge

The Painted Lady is an annual immigrant from North Africa, usually arriving June to August, though they can arrive on the English south coast as early as January. Some arrivals come direct from North Africa because the butterfly is capable of travelling 150km per day and continuing its flight through the night. Others come via an intermediate generation in continental Europe or southern England. In some years successive waves occur and may come from different sources.

It is usually a large black, orange and white patterned butterfly which looks dark orange in flight. Males and females are similar, with females often slightly larger. When it emerges it can have a salmony pink tinge to its wings but this fades after a few days and some butterflies look very washed out. This may be because they have flown directly from North Africa and it’s not known if the fading is due to their long flight, or from living along the desert edges of North Africa where blown sand may act abrasively on the colour scales. Paleness may therefore indicate an older butterfly.

Occasional specimens from larvae which might not have had enough food can be very small, even smaller than an average sized Small Tortoiseshell.

The typical flight pattern is made up of several flaps and a long glide.

This butterfly can appear anywhere, though it prefers dry open areas such as sand dunes, heathlands, brownfield sites, and grass lands, particularly where there are good growths of thistles Cirsium ssp and Carduus ssp for foodplants and nectaring. Many other species are also used for egg laying, including mallows Malva & Athaea ssp, Viper's Bugloss Echium vulgore and nettles Urtica ssp. The Painted Lady often visits gardens to nectar on buddleias.

It has been suggested that Painted Ladies may indulge in 'hilltopping', a form of courtship activity also known in some other butterfly species, which involves males congregating on prominent landmarks such as hills or tall trees where they are more likely to meet up with females.

Most arrivals cross the English Channel and head northwards along coastlines or up through the centre of the country. More unusually, arrivals come in from the North Sea, and even more rarely, such arrivals may have originated in central and southern Asia rather than Africa. First arrivals are often along the east coast, especially in the south east corner of Yorkshire at Spurn NNR or along the southern edges of the county between Doncaster and Sheffield (VC63). ln some years the northward movement gets little further north than this. In most years fewer Painted Ladies are seen as you move north west.

In North Africa and similar latitudes around the world the Painted Lady is a multi brooded (polyvoltine) resident. It migrates long distances northwards in spring, sometimes as far as the Arctic Circle and Iceland but the numbers migrating vary considerably from year to year, from a few, to millions.

There is no clear pattern to good and bad years, which may be due to complex inter-relationships between weather, parasite attacks, nectar availability and foodplant defoliation in resident areas, as well as wind and weather conditions for northward journeys. However it can winter successfully in the Mediterranean area and sometimes further north, even as far north as the south of England sometimes, but overall the population numbers are still dependent on the annual build-up in North Africa.

2019 was a Painted Lady Year in that there were thousands of the butterfly all around Yorkshire and they were one of the commonest butterflies seen. In contrast very few were seen in 2020.

Once in Yorkshire, Painted Ladies are fast breeders and can move from egg to new butterfly in around four weeks minimum, although due to weather conditions this far north, the timescale is often longer.

The mating behaviour of the species is rarely seen in the wild. It is presumed that as with other Vanessid butterflies this takes place in trees or shrubs under cover of darkness but there is still a lot to learn about this relatively common species.

The light green eggs turn grey before hatching after seven to ten days. Larvae are black and hairy, covered in tiny cream dots, with almost continuous yellow lines along the sides. They feed in silk webs on leaf undersides and later make tents of folded leaves using silk threads. Larvae need warmth and sunshine for success and lots of rain or cloud can be a disaster.

Larvae pupate after developing through five instars in seven days or more, depending on the conditions. The pupae hang from leaves and come in two attractive forms, one brown with a golden sheen, the other silver-grey. The butterfly emerges after about two weeks, though longer in cooler weather.

The species is thought to be continuously brooded in North Africa where huge numbers can build up during our winter months and at some point this triggers a northward movement, occasionally even in winter, and arrivals from January onwards can happen along the south coast of England and occasionally reach further north, though not recorded for Yorkshire. Early arrivals probably die due to the cold.

Painted Lady migrations occur in various ways from broad fronts l00 miles across, to bands of a few metres wide but many miles long, and linear streams, with butterflies passing one behind the other for hours at a time.

• Butterfly Conservation priority: Low

• European status: Not assessed

There are at least 32 named variations none of which are common and many of which are variable in themselves. The American Painted Lady C. virginiensis (not to be confused with the normal Painted Lady which also occurs in North America) is very similar in looks and occasionally turns up in the western half of Britain and in Ireland.

With thanks to The Butterflies of Yorkshire edited by Howard M Frost