I don't know that there is anything you can do. I suppose if it doesn't move fora few hours, you could try to super glue it to a piece of paper and re-hang it somewhere and hope it continues to do its thing. Can you still see any of the silk attached to its tail that it was hanging from? If you could sneak a pin through the silk and re-hang it, that might be worth a try, also. But remember, in nature the chances of it surviving were slim to none. So, it would also be perfectly acceptable to put it outside for some other creature to have as a meal, and the circle of life would continue. You still have the other cats to protect and release into the wild to make more butterflies. Good luck with this frustrating situation. It is sad when our efforts aren't as successful as we hope.

Martha

I had a black swallowtail caterpillar whose silk girdle somehow broke, and the poor guy was hanging upside down from the little pad on his butt. I gently got him off the fennel stem he'd chosen and laid him on the bottom of the cage. He pupated just fine.

If yours wasn't injured in the fall, he should be OK!

Ditto to what weed30 said. Caterpillars don't have to be attached to make their chrysalis. Just yesterday, a spicebush swallowtail 'attached' itself to the bar of its cage, but a few hours later, it was dangling by the sling, which was also very poorly constructed. I didn't see how it could pupate like this, since they 'wriggle' a lot at the important moment before casting their old skin off. I VERY gently and slowly detached the silk from the bar, while cupping the cat in my other hand. It's important to NOT pinch or nip the cat, which will cause death. I laid the cat on the floor of the cage, and it had successfully made its chrysalis this morning - YAY!

Sherry