attempting to preserve/ freeze dry Monarch caterpillar
I'm going to post here because I did a little research and found that similar subjects have been discussed in the archives. I meant to bookmark those, but I must have forgotten to after going to bed last evening, so.....
I have a couple of expired Monarch caterpillars that I want to place inside a glass dome along with butterfly and chrysalis to show the life cycle. While the butterfly is easy enough to dry, I am totally stumped with the caterpillar. I've tried the following methods with failure:
1) Inflation. Main problem is extreme color loss. Yellow is no longer yellow and black in some cases.
2) Silicone. Same process as inflation, except no heating. Once contents are forced out, cat is immediately refilled with silicone caulk. I found out about this from an entomologist who has been doing this successfully since 1995. However, despite repeated attempts, I still end up losing almost all color with much blackness after a few hours especially.
3) Microwave silica gel heating. Just like is done with flowers, undrained caterpillar is placed between tissues with silica gel on the other side and microwaved gently until hard. Problem I had is even with microwave at 25% power, there is still a sudden heating that ejects the caterpillar contents as a solid, so even though color seems better preserved, cat is much more shrivelled.
4) Dehydration of water and replacement with propylene glycol. The liquid of the cat is replaced with the glycol after a 24 hour soak, but drying still results in a shrivelled up black cat of about 1/4 size.
These were the nearly "instant" options I tried (by instant I mean a couple of days time frame), but none of them worked. Right now, I have two caterpillars indirectly on silica gel sealed jars in the freezer. Based on information I was able to obtain, this is the best method, without using expensive lab equipment, but it's going to take 3-6 months. I'm hoping to speed up the process without excessive cost, so that's the reason for this post if someone has any cost effective suggestions to share. I want to preserve a chrysalis or two also, and I am assuming I should be able to do it the same way as the cats in the freezer. In the meantime, I came across perhaps a cheap possibility of speeding up the process, again from a prior thread on here, but didn't save it:
Now a family member actually has this exact aspirator, but not having lab access to glassware or tubing of any type, I'm not sure what I would need. I'm toying with the idea of giving this a try if I can come up with cheap enough materials. I'd first like to find out what type of adapter is needed to connect this to the faucet, so any suggestions would be welcome. For tubing, would the same tubing used for auto work for this? What type of valve is he referring to, one for plumbing? He said he has trouble finding suitable ones that worked correctly.
Your thoughts would be welcome and appreciated. Even with the aspirator, it's still going to cost for the other materials so it would be nice to find a cost effective source.
Ichthyophthirius
Posted: Fri Sep 22, 2017 3:14 pm Post subject: Re: attempting to preserve/ freeze dry Monarch caterpillar
ctron wrote:
I came across perhaps a cheap possibility of speeding up the process, again from a prior thread on here, but didn't save it:
Do you mean you didn't save the PDF file? The link isn't working but the PDF is still there! Just copy the full line directly into your browser.
It's a nice paper! Many of the materials should be much easier to get hold of nowadays. If you search "glass stopcock" https://www.picclickimg.com/d/w1600/pict/322217250355_/Straight-Adapter-With-Glass-Stopcock-Hose-Connection.jpg on Ebay you can find some very cheap ones (though I don't know how good they are).
rjlittlefield
Location: Richland, Washington State, USA
Here is a direct link, which I have generated by replacing those troublesome parentheses with their %-code equivalents inside the URL tags:
I have also updated the links in my two earlier posts that referenced this paper. Thanks for the prompting to do that.
--Rik
Thanks for noticing and fixing the link guys. I knew it didn't quite work the entire length, but figured someone would notice and fix.
I did find some 1/4" tubing used for cars. It isn't the gum rubber kind maybe used with the vacuum systems, just curious if I could use that. Because it's easier to get, for all tubing between the trap and dessicator jar, I was going to use 1/4". Going into the trap from the aspirator though, I'll have to use 5/16".
Trying to order all this online and maybe separate shipping depending on where I get it is going to maybe be costly. Would a Home Depot, Lowes, or even a small town hardware store have any of these items?
For the jars, I was going to use these:
They seem to match or nearly match the kind he's talking about. I'd still need to add the #7 stoppers which I assume would fit these jars.
Last edited by ctron on Fri Sep 22, 2017 4:39 pm; edited 1 time in total
GrayPlayer
Would a process used to dry flowers work?
Fred H.
GrayPlayer wrote:
No, I already tried this. It ends up wrinkling the specimen pretty badly.
Well, I'm pretty much giving up. One of the caterpillars I started freeze drying via the long method (several months) started turning black tonight. I don't know if it's all caterpillars, it must not be because some people have success, or certain ones. I'm noticing with the Monarch that *any* residual trace of its original contents, even after emptying the body, causes the color to be lost and even turning dark. The best success I had was almost doing a full dry with the silica gel method and microwave. Of course, then it was too dry to try refilling with silicone or anything else, so ended up partially shrivelled but that was the one with the best, although weak, color.
I'm out of caterpillars so there will be no hunting down the aspirator stuff. The only way I'll make up this dome now is if I can find successfully dried Monarch caterpillars or a realistic looking replica, both I think are long shots at best, so I'm stopping here.
Should anyone have success, particularly with Monarch, please share at some point in the future.
zzffnn
" 2) Silicone. Same process as inflation, except no heating. Once contents are forced out, cat is immediately refilled with silicone caulk. I found out about this from an entomologist who has been doing this successfully since 1995. However, despite repeated attempts, I still end up losing almost all color with much blackness after a few hours especially. "
I have no experience on this. But different "silicone caulk" preparations have lots of different chemicals in them, and some of those chemicals can bleach colors. Is it possible to ask the entomologist and follow with his EXACT protocol and brand/ chemicals?
A standard way of exhibiting insects that loose their colours (e.g. dragonflies) is to make a good dry preparation and then paint them using model paint 
(no joke)
BTW, I really liked this idea to display a butterly life cycle: 
zzffnn wrote:
Yes, that information is available and was revealed actually here in another thread. Unfortunately, it doesn't seem to be available. I was using standard bathroom clear caulk, a "neutral" formula.
Ichthyophthirius wrote:
Believe it or not, I actually tried this on one of the darker specimens where the color wasn't too far gone. However, I'm no artist and it turned out to be a disaster.
I've inquired in another forum of perhaps a way of making a mold of the chrysalis as I have two now. So far, no responses. They make molds of other fragile objects, just thought someone might have an idea.
Well, as luck would have it, I came across two more specimens today along with one intact egg. I'm beginning to think that the reason I'm having so much difficulty is that almost all of the cats I found were within a day of transforming and I have repeatedly read that cats in such states don't make good candidates for preservation of any type. With the egg, I may have another shot if I don't let the cat get too large. So, I've decided to continue on and start gathering the equipment using the aspirator technique. I'm having some difficulty sourcing some of the parts needed, just too darn bad there isn't any firm close enough that has public sales of scientific glassware.
MarkSturtevant
Posted: Sat Oct 14, 2017 9:31 am Post subject:
I am going to spitball some ideas.
1. Whatever methods you try, practice on cats that are common, so you can try lots of different methods. You can return to the monarch cats (which are a bit harder to get) once you have some good candidate techniques.
2. From an article at Oregon State Entomology: "Larvae of most insects should be collected, boiled in water to "fix" their proteins and prevent them from turning black, and placed in alcohol. Larvae should be left in hot water for 1-5 minutes, depending on the size of the specimens, and then transferred to 70-80% alcohol. I would leave out the step for preserving in alcohol].
From a website at Texas A&M called BugHunter: "Boiling larvae and KAAD. Many insects, especially caterpillars, lose their color when preserved directly in alcohol. To improve the appearance of these insects they may be killed in boiling water for a few seconds or first killed in a solution called KAAD (available from a source of entomological supplies). KAAD consists of a solution of: 1 part kerosene, 7-10 parts 95% ethyl alcohol, 2 parts glacial acetic acid and 1 part dioxane.
Freeze drying. Larval stages of butterflies and moths can be preserved dry (versus in alcohol after being preserved in boiling water or KAAD) by freeze-drying them in a vaccum. Specimens retain color and hair (setae) patterns better using this method. Special equipment is required, however."
3. If these seem useful, you can do the procedures on a freshly killed cat that has already been eviscerated. They can then be inflated after the preservation procedure.
4. I remember years ago, as a teenager, I had inflated and oven-dried a monarch cat. The yellow color faded, and the white turned grey. I did not take it further, but I suppose one could "restore" the colors with modeling paint and a fine brush, working under a dissecting microscope. I would first practice painting on a different object to get the technique down.