Those look big enough as long as you don't put more than one or two cats in the cage. It would be better for the butterflies if they had more room to exercise their wings and flutter about a bit before you release them, although, if you wait until they're really trying to fly, you could put them on the branch of a tree or bush, and they'd probably be okay. There's always the (remote) possibility that they could be taken by a predator if their flying skills aren't well honed.
I use reptile cages, which make good caterpillar cages, also. My favorite size is the 38-gallon size - I'm linking you to the site where you can buy it for the best price - they also sell the 22-gallon cage for the best price, if you prefer, it's still big enough. In the link, they show the cage on its side with lights on top - for caterpillars, it's best to stand it up, and, of course, you don't need the lights. These cages are SO convenient, they give your cats plenty of room for all they need to do, you can attach water picks to the inside of the mesh covering with the host plant material in it, or you can put your cuttings in other containers on the bottom of the cage - I do it both ways. They can easily climb up the side of the cage and "hang out" until their wings are ready, and then exercise their wings properly before you release them, which you can easily do just by unzipping the cage.
Sherry

Here is a link that might be useful: Reptarian Cage

Thanks so much for the advice!! One of the cats has attached his "sling" and hanging horizontally on a stick in his little "crib". When chrysalis forms and hardens, should I move him into one of these reptile cages? or just leave him where he is? Also, when do you think I can expect him to emerge or eclose? And is there anything I need to do when this happens? Anything I should be prepared for as far as problems and making sure the process is going the way it is supposed to be going? How long should they newly emerged butterflies stay in the enclosure? Also, my neighbors have two outdoor cats, and I was thinking maybe I should take them somewhere more secluded to set them free, so they would have a better chance at surviving, tons of birds here too. If you can point me to a link or site where i can find out some detailed information about what to expect, that would be great, and would save you the trouble of typing it out! Thanks so much for taking the time to answer my questions!!! I really appreciate it!!

If it were me, I'd move the sticks with the chrysalides on them to the reptile cage when it comes, assuming you're going to order one? Giant swallowtails, like tiger swallowtails, are big butterfliles, so they need plenty of space. You can prop the sticks up against the side of the cage or put something in the cage to prop them up against or put them in a water pick and attach the water pick to the inside of the cage with florist's wire. It really doesn't matter - the butterfly will find the side and/or top of the cage if given the opportunity.
I just got another idea - you could insert the sticks into florist's foam. I think it's better for the chrysalides to be in their natural positions, which can be heads up or horizontal, just not heads down.
When the butterfly emerges, it will crawl to the side or all the way to the top of the cage and hang there - it should stay there at LEAST four hours, preferably six hours or even more. If you see the butterfly flying around frantically, then you know it's time! You don't want a giant swallowtail to stay in their cage too long, especially the males, because they get so anxious to leave, I've seen them knock off the spoon shaped tails on the end of their wings - it's depressing to release a butterfly, already damaged! Butterflies like to be released to sunshine - they're supposed to be solar powered, which is why they bask - so if the day happens to be cloudy or rainy, the butterfly may prefer to "hang out" until the next day, which is fine, but by the next day, even if it's still cloudy, it'll want to leave. If you release your butterfly when it's well able to fly, the chances of it being taken by a predator are VERY slim.
Hmmmm... I can't think of anything else. My fingers are tired!
Good luck!
Sherry

Thanks again!! That info is very helpful! I ordered the cage already! So, when I transfer them to the new cage, just make sure to anchor the sticks at same angle, in same position they were in the old "cages", right? The other cat is pacing around his box now, climbing up and down and back up, like the other little guy did yesterday before he attached himself. I was wondering if it is possible for them to not find a spot they feel is suitable for pupation, and end up wearing themselves out and not following through? because the box I have the other one in is a lot smaller than the one other cat is in. If he wanders around for longer than a certain period of time, should I move him to a "deeper" container of some sort? Do they look for a spot that is a certain distance above the "ground". Also, he is wandering, hasn't eaten since yesterday, but he has not yet eliminated all the waste like the other one did yesterday before he attached himself and started process of pupating. The only thing he has eliminated is the regular frass thus far.

Oh, and also, how can tell when they are getting ready to emerge from the chrysalis? Is there anything I need to be looking for? Does it change in appearance? ALl the info I have found is conflicting,some things I have read say they will be ready in two weeks, some say not until spring, or summer, or up to a year, so I have no idea when to expect their arrival, lol, and would like to make sure I am here when it happens.

I imagine the one that's still wandering around is doing so because it hasn't yet purged. I've never had a cat to collapse because it was tired of wandering - when it takes a long time for the purge to come, they just pause every now and then and rest - eventually, they all assume the position and pupate. Occasionally, one will assume the position, but not be able to successfully pupate - when that happens, they usually partially pupate. If this happens to one of yours, you can dispose of it, but it very rarely happens with giant swallowtails. GSTs have been some of the easiest cats for me to raise - nearly all of them make a perfect butterfly.
It usually takes about ?3 weeks for them to emerge. At this time of year, you may have some that will overwinter, but most will emerge. I've never been able to tell by their appearance when a GST is about to emerge - the butterfly doesn't start showing through the pupal skin a day or two before emergence, like with palamedes swallowtails, monarchs, spicebush swallowtails, etc. One morning you go check on your leps, and voila! an adult GST is hanging from the top of your cage!
You'll be glad you got that cage - it makes things so much easier!
Sherry
P.S. Your posts have brushed up my typing! :)

Sherry,

Do you mind my asking, do you keep this cage outside or inside? The reason I ask is I wonder if the mesh covering has openings small enough to keep that tiny fly out that can so damage the little cats if used outside. I've already forgotten what the fly is called but it begins with a C and it lays it's eggs inside the little cats and of course, eventually kills them. I read another post somewhere that suggested this little fly can get through regular window screen? Have you heard of this situation?

Mary

The only parasitic fly that I'm familiar with, Mary, is the tachinid fly. I brought in some tobacco hornworms once, and instead of a moth emerging, JILLIONS of horrible flies came out! It was like something out of a horror movie!
Tachinid flies are bigger than houseflies, so they can't begin to get into a reptarian cage - the mesh is VERY fine. The only insects that have ever turned up unexpectedly in my cages are an occasional tiny gnat, but they may have gotten in when I unzipped the door, and I didn't realize it.
Here's one of the tachinid flies that prasitized my hornworms -
{{gwi:457399}}
Sherry

Yikes! That fly is scary looking.

Good to know about the mesh covering. Thank you for your reply. My son was going to build me a butterfly house on legs so I wouldn't have to bend and set it up on the deck. Then I begin to read about all these horrible predators that can get to the little cats and I backed off on that idea.

I still need something that's large enough for the butterflies to eclose in inside so perhaps this is just the cage I need. I assume when sitting on it's end/ long side upright, the zippered opening is still on a side. I'd like what would be the top to be where I wouldn't have to ever disturb it.

Thanks again for taking the time to answer my question.

Mary

mary_litterockar asked: "fly can get through regular window screen? "

Yesterday, from the OUTSIDE of a relatively fine mesh net bag, medium sized flies (not wasps) were after two large Orange Barred Sulphur caterpillars that were on inside (preparing either to moult or to pupate). I thought Tachinids, but now am uncertain because their damage occurs after eggs hatch; in this case, the caterpillars died shortly after the attacks.