Painted lady (Vanessa cardui)

V. cardui occurs in any temperate zone, including mountains in the tropics. The species is resident only in warmer areas, but migrates in spring, and sometimes again in autumn. It migrates from North Africa and the Med to Britain and Europe in May and June.
For decades, naturalists have debated whether the offspring of these immigrants ever make a southwards return migration. Research suggests that British painted ladies do undertake an autumn migration, making 14,500 km (9,000 mi) round trip from tropical Africa to the Arctic Circle in a series of steps by up to six successive generations. The Radar Entomology Unit at Rothamsted Research provided evidence that autumn migrations take place at high altitude, which explains why these migrations are seldom witnessed. 

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