A monarch larvae that was wild caught and pupated in my butterfly tent just eclosed this morning. She looked great. She was strong and able to inflate her wings fully. After they had dried for some time, I decided to let her go, but not without first doing a test. I put some scotch tape on her abdomen to pick up a few scales. I put the tape on a glass slide and looked at it under the microscope at 400 magnification. I was surprised to see she was heavily infested with OE spores.
I pondered. Should I let her go? She seems healthy. She will spread this though. I remembered something I read on monarchscience.org.
The answer is not simple, and basically I probably shouldn’t have taken this 5th instar larvae into my butterfly tent in the first place. In Florida, OE is everywhere. Since I got this larvae at a very late stage, it probably had the spores before it ever got to my enclosure. One scientist says in this case, I can release it. The other scientist says euthanize it. https://www.monarchscience.org/single-post/what-to-do-with-oe-infected-monarchs-that-you-raised-it-s-not-that-simple
Since she looked healthy I decided to let her go. Now that she’s gone, I’ll clean the enclosure with a mild bleach solution. I prefer to let larvae alone to do their thing, but this one in particular was running out of food when I found her. I know! That’s not a good excuse. Anyway, I’ll keep my eyes open for other wild larvae and try to watch them from a distance.
Buzzing Blossoms 