While hacking back the topgrowth of the ivy on the wall at the bottom of my garden, so I can see what I'm doing while I remove as much as I can, I had a butterfly whizzing round my head for a few minutes. Either a Red Admiral or a Small Tortoiseshell, I think, as I was so surprised as I saw none near here last year, and consider April early for butterflies in Northeast Scotland anyway, that I didn't get a proper look at it, other than to say "Gosh, a butterfly" Then I had a thought that it might have been overwintering in the ivy (so not a Red Admiral), and I had a vague recollection of reading about this years ago. So I stopped attacking the ivy, and came in to look at the books. No luck. Do butterflies overwinter in ivy thickets?
Don't know, but I'd not be at all surprised if they did. Ivy flowers in the late autumn are an excellent source of late nectar, and the foliage offers dense cover that will protect them from both bad weather and predators.
It looks as if I need a more recently published insect book. Mine plainly states that Red Admirals are continental visitors if seen early in the year, the internet says they hibernate here, and indeed often in ivy. So that's me saved a real chore until late autumn, and even then I'll leave the flowers and fruit. I'll just clear the young growth from the border, and leave the clump on the top of the wall for all the stuff that lives in it.