I would leave it where it is and monitor the plant. If it looks like the plant will run out of leaves, then I would move it.

And as docmom stated, it will have pupated and flown away within a week or two.

docmom and mblan13- i checked this morning after last night's downpour (central nj) and almost half the plant was gone. the caterpillar was totally exposed. i moved it to a bushy plant with loads of leaves and protection from predators. it immediately began to do what it does best - creep and poop. it's already almost invisible.

i think i'm replying the wrong way.

2 hours ago it was smiling and eating and now it's gone. i searched like crazy and i have to guess that a bird or something equally large got it. i had thought that it was poisinous to birds so that surprised me. lesson learned. i'll try the upside down tomato cage idea when i see the next one. i don't see any eggs and my tuberosa are starting to yellow. any ideas why? i'm not spraying but i don't see any signs of insects. any thoughts out there?

It may have crawled onto another plant to pupate.

i hope so. i searched but there are a lot of plants and i couldn't find it. this is more nerve-wracking than raising kids.