I put eggs and hatchings in a smaller container for that reason then transfer to a larger container later. Hopefully if they're in a small enough container, they can find their way back on their own. I keep covers on the containers with very small holes so they can't escape. Also make sure your cuttings are fresh. You can wrap the ends in a damp paper towel to keep them from drying out.

I agree, it does seem like they have a death wish. No wonder caterpillars have such a low survival rate.

Which of your plants do you find the most giant swallowtails on? I grow prickly ash and rue for them. I have a wafer ash but it's less than a foot tall. I've never grown gas plant so I will have to check that out.

Hi Cathy. If there are bigger caterpillars in the vicinity of the smaller, then the smaller might be practicing the innate deference behavior that I have observed in other species : they defer to the bigger even without having been bullied. I solve it by separately housing different sizes.

Also I have observed voluntary isolation in conditions of high population density.

It sounds like you’ve got a bit of a challenge with those giant swallowtail caterpillars wandering off. From what I've experienced, it’s not uncommon for caterpillars to leave their host plants, especially if they’re nearing a stage where they need to pupate.

It’s also worth checking for any pests or disturbances. Beneficial insects can sometimes encourage natural behaviors in plants and caterpillars that promote a more balanced environment, making them feel safer staying on their host plants for longer.

Christie, It sounds like your experience with the Giants is about the same. It's a heck of a thing trying to get them to stay on their host plant. I don't know which is their favorite plant...they hate them all equally and so keep crawling off of them. My daughter ended up getting some small cups with lids and put them in those. That seemed to work much better. I have rue, wafer ash, and gas plants for their host plants. They lay most of their eggs on the wafer ash. After that is rue followed closely by gas plants.

Hi four, That makes sense what you say about the smaller cats deferring to the bigger ones. In my case here, they were all the same size, super tiny. I agree that it is probably best to keep them separated by sizes. I know that we have cannibalism sometimes, but that's mostly the Pipevine Swallowtails that do that here. At least that's the way they act here. Who knows the differences in various cats' behaviors depending on the location that they are at. Observing Lepidoptera is so very interesting! It sounds like some of your Giants can be wall flowers in cases of high population density. ;-)

Cathy, ultimately how did it go with the caterpillars about which you started this thread?

A few died, but after we moved them into the small cups, it worked much better. I'd say about 2/3 of them made it to pupation.

Thanks for your follow-up Cathy. I'm eager for my wafer ash to get bigger. Something else was eating it last summer. Some kind of leaf roller things that almost completely defoliated it for awhile. I'm pretty sure it was still alive at the end of summer but not looking great so we'll see.

I only have three rue plants but read recently that it will root in water so I may try that when it leafs out again.

Christie, I've been able to root rue in water, so definitely try that. Sorry to hear about those critters getting after your wafer ash. What I have get after mine is those darn potato beetles. I really don't know any easy non-toxic way to get rid of them. They are a pain, and I hope they're not so plentiful in MO like they are here in central PA. They're one of my most hated insects, but there are plenty on that list, mostly ones that get after the butterflies or their host plants. My daughter and I used to raise Monarchs, but the last year we did, so many of them died from some illness and we were so discouraged that we gave up on raising them and concentrate on other types. I used to hate how the milkweed got so full of oleander aphids, another hated insect of mine. I still have milkweed but the Monarchs are on their own. It was starting to take over my life, as it is very time consuming. Of all the butterflies we've raised here, they were definitely the most challenging. I don't need all that drama in my life. Ha. They are a beautiful butterfly though.

The internet says we have Colorado potato beetles here in Missouri and that might be what I've seen on my prickly ashes. Thank you Cathy. I didn't have a name for them There are typically dozens or maybe hundreds of beetles and they don't leave much for the giant swallowtails to eat. It's disappointing. I WAS finding quite a few giant swallowtails on my prickly ashes before the beetles found them and now I think the butterflies see the beetles and just go elsewhere. I'm lucky to find one each summer.

My new strategy is 3 little potted orange trees. I thought maybe that would attract the Giant Swallowtails and then I could get branches from prickly ash or from my rue to feed them. It didn't work last summer. I managed to keep my orange trees alive in the house over winter though, so I'm going to set them out on my patio when it's warm enough and watch for babies. I have a lemon tree too. I don't know if they like those or if they will lays eggs on citrus at all in Missouri since citrus is not hardy here. The closest thing we have is trifoliate orange which is related to citrus and not very edible. It supposedly grows wild in Missouri but I don't think it's common. I've never come across one anyway.