A few minor things from the continent: - the Map is highly mobile, colonised Netherlands in 15 years (meaning a spread of 20 km per year). - at present the speed of expansion in Finland seems to be around 600 km in 10 years (so 60 km per year), though some might have come from the east. - we now hav...

Another one was found inside a house. So at least some of them hibernate at the same places a A io and A urticae, which makes it possible they are found in winter. And we know now for sure they went into hibernation in NL, I guess the same applies to the UK.

Yesterday two N xanthomelas were found hibernating in a cellar maintained for bats, together with Peacocks (Aglais io). So it might be good to keep in mind that they might be overwintering at places where A io is found as well, so people who count them in cellars etc should be aware of it.

Regarding experience from previous years in Scandinavia (with quick hibernation after emerging) and the fact that they already started to hibernate in Sweden, I would not be surprised if we have seen most of them. The next few days will make it clear, as the wind this morning turned NE again and it ...

Here in NL the invasion seems to have stopped. Yesterday (Sunday 20 July) the species was only reported from one site, today none (but it was a very rainy day). Tomorrow the wind will turn NE again and we hope for a new influx. However it is unclear what happened to 'our' butterflies. Reports from S...

Martin, thanks a lot for your detailed report from Denmark. I got a bit confused about what you wrote about the direction of the migration: ' In addition I saw several fast and high flying large Nymphalidae in the days around July 11. all migrating east …and to the east all though rather far Great B...

Check out this animation of how fast this species colonised Sweden within three years: http://larspett.cartodb.com/viz/19857862-0cdf-11e4-80e6-0e73339ffa50/embed_map?title=false&description=true&search=false&shareable=true&cartodb_logo=true&layer_selector=false&legends=true&a...