Monarchs Emerge But Aren't Viable

by Susan
(Los Angeles)

I found an egg!

I found an egg!

I have 3 milkweed plants and have watched in awe as dozens of caterpillars eat and grow.

I find the pupa and watch them but some of the butterflies that emerge aren't viable. Their wings are crumpled and they can't open and pump them. Seems like some of the pupa take a very long time to develop.

What's going on?
Do monarchs lay eggs and go through the whole cycle year-round?

Karen's reply: Susan, it sounds like you have a parasite problem (probably Ophryocystis elektroscirrha). This parasite is spread from spores on the milkweed to pupa, then butterfly and egg.

Yes, there are some Monarchs year round, especially in Southern Florida and also, Southern California (where you are!). The above parasite is more common on year round Monarchs.

Your egg picture is fantastic! Thanks for sharing.



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