Mark, that's great news. Nice picture. That's a beautiful milkweed species thanks for sharing. I think my final Monarch cat of the season just pupated.

Chrissy, get a collapsible net clothes hamper ($14 on Amazon) turn it upside down on a table covered in brown paper or packing paper (no printed newspaper). The cats will crawl up the mesh sides and pupate. You can easily remove the paper to dump the poop and reuse it until it's too soiled. Dump poop once or twice a day. This photo shows the set-up with fennel and Black swallowtail cats. So for Monarchs just pick leaves and lay them on the paper in the bottom. If you do leaves then you will probably have to feed twice a day due to the leaves drying out. It's cheap and easy. After all the chrysalides have eclosed then just wash the hamper with water and chlorox spray and reuse. :) Anna

Thanks! I have never had to euthanize a caterpillar or butterfly before and wanted to make sure that was the right thing to do in this case. No doubt it was. I heard it is good to put them in the refrigerator first so that it isn't quite a shock when they go in the freezer, which is my plan. When I removed them from the enclosure, they seemed light and on the dry side, especially the first two that attached to the top of the enclosure. If anyone who has any idea what would have caused this, please let me know. I did some searching online and found information about Black Death and other possible reasons, but nothing I read seemed exactly like this situation. The cats I had were probably 3rd to 4th instars when I got them and had very little to no milkweed up to that point, so they had most likely gone through a period of malnutrition. Once I got them, there was a constant supply of milkweed and cantaloupe. I use NO chemicals in my yard, pesticides or herbicides. I had other caterpillars this summer that did just fine and also ate cantaloupe, although, not the same cantaloupe. I rinsed off the cantaloupe before cutting it and putting it in the enclosure, but now wonder if there could have been some trace pesticides on the cantaloupe??? So... my hunch is that either malnutrition/starvation during their development led to their demise, or there was something bad about the cantaloupe. Or, they could have come into contact with chemicals before I got them. All I know is that they seemed happy as can be and were steadily growing until they attached to the top of the enclosure, but after that, they were not able to form into a chrysalis. : (

I did some research on this and found that sometimes Monarch caterpillars will vomit green when they eat a leaf that has an insecticide on it. Then I read this; "Overcrowding will cause Monarch caterpillars to spit out green fluid. If your caterpillars are spitting green fluid but you are positive they are not exposed to poisons and they do not act poisoned in any other manner, try reducing the number of caterpillars in one rearing container." This