www.ukbutterflies.co.uk

I was back in Annecy (Hte Savoie - France) in October this year and to my delight, I found several Geranium Bronze right below my mum's flat and more behind the Centre Bonlieu near the lake. It was still hot there (25 degrees) with a lot of sunshine but I had never thought I would find these little blighters right in the heart of the Alps. It was a nice surprise as I had never seen them before.
It won't be long before they appear in the UK or is the climate not suitable here? Does anybody know how far in Europe they have spread already?
Sylvie

Small world - at the end of October I was visiting my son and his family at their home in Ville-la-Grand, also in Haute-Savoie. I was surprised and delighted to spot a couple of tiny butterflies in the front garden and they turned out to be Geranium Bronze. First time I had seen them.

Outside continuously heated greenhouses I don't think they're established much further north than N. Italy, S. Switzerland and similar latitudes in France.

The British climate is inherently inimical to heat-loving, continuously brooded, short life-cycled butterflies like this, not just because of the average temperatures but because of the length and mildness of the winters. In favoured spots in the Alps, as readers of my diary will know, butterflies can fly pretty much all year round - and when they can't it is usually sufficiently cold to keep them properly torpid. I think things would have to change a lot for geranium bronzes to become established in Britain outside greenhouses. Nevertheless, climates change and butterflies evolve! Maybe those southern French populations will little by little creep north ...

Guy

As Geranium Bronze uses a food plant which cannot take frost -ivy leaf Geranium- in all stages of its life, it can never establish in Britain unless we get a frost-free climate. Perhaps they could survive on the normally frost-free Isles of Scilly and far west of Cornwall?

Thank you Andy, Guy and Essex Buzzard. Will see in the future how this species will fare.
Sylvie

They've even turned up in Britain occasionally, Sylvie. I guess the early stages accompany pelargoniums into Europe and some of these pupate and emerge as butterflies, although they can only survive in the warmer spots year round, such as the mediterranean coastal areas.