Ann, remind me what caterpillar species you're raising? Yep, they usually hang out for about a day. Then they molt in like, five minutes. After a few more minutes, they turn around and usually eat the skin. A free meal is a free meal, I guess. And they do not eat the head capsule. Some researchers collect the head capsules in order to document how many instars a caterpillar has. Butterflies usually have five instars. When they hatch is the first and then each molt is another instar. But when they make the chrysalis, that's the next phase of life and doesn't count as an instar. You guys remember the life cycle: egg, caterpillar, pupa, adult.
I haven't done a PSA in a while so here goes. Never move a molting caterpillar unless it's in some kind of mortal danger! And even then, it would be better to remove the danger and not the caterpillar. You see, when caterpillars molt, they first lay down a layer of silk. Then, they attach themselves to it. The head capsule detaches (which is what makes it look like it's sitting low on their head), and they puff themselves up with air to loosen the skin. Now, once attached to the silk, with rare exceptions (Monarchs seem to be one) they cannot silk anymore. I believe this is due to either the head capsule detaching or covering their spinnaret. I'm a little unclear about if the spinnaret is on the head capsule or under it. Anyway, they can't silk anymore. They need that silk to provide resistance when they start to pull. Imagine trying to take your sock off without pulling on it. That's what it's like.
So what do you do if you accidentally knock one off? I've done this at the museum and at home. If your other caterpillars or the one you have was nice and silked up your container, you can sometimes find a silky patch to stick the caterpillar to. Hold it there for a few seconds (okay, maybe more like a minute) and see if it will stick. The other thing to do is watch it. Watch and wait. Once it starts to molt, you can use a pin or maybe your fingernail and hold the back end down. The hard part is NOT pinning the new caterpillar underneath. This is not easy and I have failed many times. So the best thing to do is let molting caterpillars lie.
I just watched "Jurassic Park II: Lost World" in preparation for the new movie. And there's a pretty good lesson there about how nature doesn't need our help, and would probably do great if we disappeared entirely. Which leads to some plot holes because if a hobbyist who raises butterflies can figure this out, shouldn't actual professionals already know this? Anyway, when I was new at this, I didn't really know how to tell if a caterpillar was molting. I'm not even sure I knew they molted. So when I saw them sitting in one place for a long time, I would get worried they weren't eating and I would move them on to a leaf to get them to eat. And they would die. Didn't take me long to realize what I was doing and not do it anymore!
Well, my hockey team won which means my family will stop screaming. I had my headphones on during the movie so the only screaming was people running or being eaten by dinosaurs. Mom has baseball coming up since we're playing on the West Coast so I may have to keep her calm. Oh, and the horsie won the Triple Crown!
