We see at least one painted lady almost every year but we have never seen the large numbers that have been reported in some years, such as 2009 and 2019. Whenever we do see one I spend patient time with my camera in an attempt to take a photo of the underwing, where its colour and patterning is most spectacular.
We've had a lone painted lady on our michaelmas daisies and verbena for the past few days - above - and seeing it motivated me do some more research on this insect's unusual life cycle. For a start it's a very successful butterfly, occurring right across the world except in Australia, some of South America, and Antarctica and the Arctic It's the only butterfly species ever to have been recorded from Iceland.
We've had a lone painted lady on our michaelmas daisies and verbena for the past few days - above - and seeing it motivated me do some more research on this insect's unusual life cycle. For a start it's a very successful butterfly, occurring right across the world except in Australia, some of South America, and Antarctica and the Arctic It's the only butterfly species ever to have been recorded from Iceland.
The most remarkable aspect of its lifestyle is its migration. The painted ladies we see in Britain originate from a Moroccan population, part of which flies north. The reason for some migrating isn't clear - it may be overpopulation. Those that set off can travel at up to 30 mph through their two-week lifespan, so an individual could in theory cover 400 miles. Sometimes they fly low, at 2-3m above the ground, sometimes as high as 500m.
The butterflies don’t make it to the UK in one go but stop along the way to breed. Their progeny can be produced quite quickly so the next generation continues their parents' northward journey. They usually start arriving in the UK in May or June.
Their first task is to feed on nectar from flowers like our michaelmas daisies and verbena. They then breed, and this feeding and breeding continues through the summer until late autumn, when the broods fail; none survive the cold British winters. However, in September some butterflies attempt to migrate back south to the continent and thence Africa. This southerly migration in years of abundance can be a spectacular sight, with many hundreds of thousands being recorded on passage.
So the two-way migration is not undertaken by individual butterflies but is a series of steps by up to six successive generations. Thus the painted ladies which return to Africa in the autumn are several generations removed from their ancestors who left Africa earlier in the year.
So the two-way migration is not undertaken by individual butterflies but is a series of steps by up to six successive generations. Thus the painted ladies which return to Africa in the autumn are several generations removed from their ancestors who left Africa earlier in the year.
The same sort of migration occurs elsewhere. For example, the painted ladies we saw in Canada have their 'base' in Mexico. Their migration is even further, up to 15,000km - see post here.
The painted ladies' migration is truly a wonder of nature - and all achieved by an insect which weighs around 0.5g.
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