I had a rude awakening to one of the perils butterflies and caterpillars face. In mid-spring, expecting the butterfly chrysalis to hatch at some point, I brought the butterfly houses out to the porch and hung them from the ceiling. One day, checking them, I saw a delicate wasp of some sort had gotten inside the house and was trapped. Being a bit of a bleeding heart, I shooed the wasp out and felt I had done my good deed for the day. Wrong.
Two more wasps, surprisingly to me, also found a way into the house. I let these out also. Afterwards, I looked at the seven chrysalis on the sides. What! There was some type of hole in the sides of a few. I knew some parasite had attacked them.
When another wasp suddenly appeared in the house, I knew that it would not appeal to my softheartedness; I squashed it.
Trogus Pennator Wasps eat the swallowtail caterpillars from the inside out and emerge from the chrysalis. I can attest to the truth of this remark. Three overwintered chrysalis have opened in the past week or two, and beautiful Black Swallowtails have taken wing after the long wait. I have seen them fluttering over the fennel plants, and sure enough, I found several of the tiny eggs on inspection.
This weekend, small caterpillars appeared. I have twelve safely in one of two, new butterfly houses. I have also kept the older one from last year. Now that I have seen one of the parasitical threats they face firsthand, I will redouble my efforts and save as many as I can manage.
I will be keeping a 2024 Butterfly Diary. The link is here: Butterfly Diary 2024. It can also be found at the top of the blog page in the bar beneath the title. I will try to create a sidebar link too. Thanks so much for following the butterflies with me.