Chrysalis Problem

[JFS61]

I've encountered a strange problem in which I've lost 3 monarchs during the past few days during pupation. Its occurring during the final stage of the process, when the skin splits open and the chrysalis begin to take shape. In each of these cases, the outer skin around the head has split open, but the rest of it does not, leaving the pupa unable to shed its straitjacket, thereby leading (sadly) to death. Is there any reason for this? Am I doing something wrong? Anything I can do to help the pupa?

[Mona Miller]

Are you rearing outside? I know that too high of a heat can stall them in their tracks.

Sometimes another caterpillar will silk over the caterpillar and when the caterpillar sheds its skin, the skin gets snagged. It is unable to shed because the silk got in the way.

Sometimes disease causes them to stall. Make sure you carefully pull the pupa that didn't pupate and carefully clean the area where it silked. Sterilize containers after each brood. Separate caterpillars that are not acting normal.

[jillians]

I seem to have the same problem. The entire thing was a surprise to me. I didn't realize Butterfly Weed was milkweed, suddenly I've got 10 cats stripping the plants bare. We had a cold front that dropped us to the 60's just as the oldest cats were starting to pupate. One attached to the stone work on the patio and looks normal. Two have attached to another plant and only partially emerged. How long should it take once the skin starts to split? Can you assist in any way without causing damage?

We're warming back up, but it was maybe 80 today. i don't think it was heat related. I'd like to help the last few make it. My boyfriend refuses to drive them to Mexico ourselves.

[Mona Miller]

Other than helping them up or relocating them after they emerge, I don't know how to help a caterpillar that did not shed its skin. It should take no more than a few minutes.

60 degrees should not have caused the problem. I've had caterpillars and pupae with stand temps of down to almost freezing and still be fine. The caterpillars do start turning darker when it gets cold. I think this is so they can absorb more light.