I am an elementary school teacher and found a praying mantis a couple of weeks ago. I put it in a jar, brought it into my classroom and the next day it laid an egg case. What should I do with the egg case? If I keep it inside, will the young hatch? If I put it outside, will they overwinter okay and hatch next spring? Your help is appreciated.
You have a couple of options. You can take the egg case (ootheca) outside and attach it to the stem of some tall grass somewhere that is isolated out of the wind. The mantid nymphs should emerge next spring after they overwinter.
You can also try raising preying mantids indoors. It would be an excellent classroom activity with your students. You’ll need to pseudo-overwinter the egg case in the refrigerator for several weeks. Then bring it back out and the new nymphs should start emerging in several days to weeks (if it is a viable egg case). From a single egg case, several dozen to hundreds of nymphs can emerge. Nymphs will feed on each other and are very tiny, so make sure you have a lot of sticks and hiding places available for the newly emerging nymphs. Mantids need a warm, (70 to 90 degrees F) spacious container with the humidity between 40 and 95%. A ten-gallon terrarium works nicely. Fruit flies, pinhead crickets, and other small insects are excellent food for young nymphs.