Painted Lady Butterflies on the Sefton Coast: The 2026 Migration

1 July 2026

Identification

Vanessa cardui is one of the most distinctive British butterflies once you know it. Wingspan 58 to 74mm. Upper wing surface: salmon-orange with black and white markings at the wingtip and a row of black spots along the hindwing margin. Underside: pale brown and cream with four small eye-spots near the hindwing margin, giving a mottled cryptic pattern when resting with wings closed.

The painted lady can be confused with the red admiral (Vanessa atalanta) at a glance, but the red admiral has deeper red bands and a much darker background. The tortoiseshell species are smaller. Once seen well, the painted lady is straightforward to identify.

In flight, painted ladies are strong and fast. They cover ground quickly and will not tolerate close approach when nectaring. Watch from a distance and let the butterfly settle before moving closer. In direct sunlight on a calm day they often bask with wings flat, giving the best views.

The Migration

Painted ladies are unable to survive British winters. The species exists in Britain only through annual migration from breeding populations in North Africa and southern Europe. The migration takes multiple generations: no individual completes the full round trip. Each generation moves northward, breeds, and the next generation continues.

Arrivals on the British coast typically peak in late June and July. Coastal sites are the first to receive migrants coming in off the sea. The Sefton Coast, facing west onto the Irish Sea, is a natural landfall for painted ladies arriving from the south-west.

2026 is a notable year for painted lady arrivals in Britain. A combination of favourable breeding conditions in North Africa and good southerly winds during the migration window has produced higher numbers than average. If you are walking the Sefton Coast dune grassland in July, you have a better-than-average chance of encountering the species.

Where to See Them on the Sefton Coast

Painted ladies nectar on a range of wildflowers but are particularly associated with thistles, knapweed, and ragwort. All three are common in the dune grassland and coastal path habitats of the Sefton Coast. The best areas to look are the open dune grassland at Ainsdale NNR and the dune face and coastal grassland at National Trust Formby.

The coastal path between Formby Point and Ainsdale is particularly good in July because it passes through varied dune grassland with an abundance of the thistle and knapweed species that painted ladies prefer. Walk the path mid-morning on a calm, warm day and check every flowering thistle and knapweed head.

Marshside RSPB reserve on the Southport coast is another good location: the rough grassland margins of the reserve hold suitable nectar sources and migrants arriving off the sea at Southport sometimes land directly on the reserve.

The Return Journey

For decades it was assumed that painted ladies arriving in Britain simply died when winter came. Research using stable hydrogen isotopes in wing scales established in 2009 that British-bred painted ladies do fly south in autumn, continuing the multi-generational migration back toward Africa.

The adults fly at altitude during the autumn return, typically above 500 metres, which is why the southward movement was missed for so long. Radar tracking has subsequently confirmed significant southward movements of painted ladies off the British coast in August and September.

The full migratory circuit covers around 14,000 kilometres in total across six generations. For an insect with a body the weight of a paper clip, this is an astonishing feat. The individual butterfly you see nectaring on knapweed at Ainsdale in July is probably the third or fourth generation from a butterfly that left North Africa in spring.