Checking on my pupae on the morning of 21 June, I was delighted to find a perfectly-formed male Buff Ermine!

Buff Ermine male, emerged 21 June 2012

Who’s looking at you?

I waited a few days to release him in case the other moth would emerge and I could release them together or see them mate. After two nights on 23 June, with no signs of the other pupa making a move, I released him on our geranium.  I kept an eye on him I did some dusking, searching for moths in the garden that night. He buzzed off around a quarter to midnight.

Unfortunately, the other Buff Ermine wasn’t so healthy. It emerged a week later on 28 Jun… or at least tried to. I found it in the morning, half-emerged from its pupa, but when I checked on it later in the day it had made no progress. It was actually stuck. It had also secreted a black fluid from the sides of its head (I think this is a defensive/stress reaction in moths of this family).

Buff Ermine female, emerged 28 June 2012

Unfortunate little moth.

This obviously meant that something was wrong – the moth must have had some deformity. Plus, the wings had dried out unexpanded so it would never be able to fly. At this point I knew that the only way to give it a chance at surviving to mate was to peel the pupal case off its abdomen. (Normally one should never interfere with emergence but this was an exceptional case.) I did this without injuring the moth, but even with the pupal case removed the moth seemed unable to walk. Its legs could move vigorously enough, but the back ones were translucent and seemed too weak to pull the moth along.

I released it in the garden anyway. It probably didn’t survive.

Why? Well, I suspect it may be due to the fact that the caterpillar pupated on a flat surface. As the pupal case is initially soft, turning hard, this meant the pupa gained some flat surfaces – and this may have harmed the development of the moth. Actually, I think the crippled Cinnabar moth’s pupa had the same problem.

Not the most uplifting blog post, I know. But hey, I released one healthy moth into the wild and I learned another lesson. So it’s OK. 🙂

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