Holly blues breeding in the garden

When we first came to live in Co. Durham in 1975 several butterflies that I had been familiar with in the south of the country were nowhere to be seen. Commas had been extinct here for a century and speckled woods, small skippers and ringlets were very uncommon. Since then they have all become common and speckled woods even breed in my garden. 

But in all that time holly blues remained rare. Until 2014, when I found one under the Byker viaducts in Newcastle, of all places, I hadn't seen any. Then in 2017 I saw another in Sunderland.

This year they turned up in my garden in Durham in spring and it's clear that they must have laid eggs on the holly hedge, because the summer generation has now emerged. This one seemed attracted to a few alkanet flowers that were still in bloom in the garden, but it has also been nectaring on devil's bit scabious, marjoram and thyme flowers. 

I'm hoping that this will be the start of a long-lasting colony here. There were numerous other reports on Twitter of holly blues in the North east this spring.

The change in fortunes of these five butterfly species here suggests that the theory that climate change, bringing a lengthening breeding season, is a factor allowing them to extend their range northwards might well be true.