I went out this morning to visit the Mantids and could only find two adults. Yesterday there were five adults and I can usually find all five very easily. Each of the mantids, whether nymphs or adults, tend not to move around much, mostly staying on one flower. I'm not sure if they are 1) just hiding from me, 2) have mated and possibly been eaten by those ungrateful females, or 3) simply flown off to start a new colony. I suppose they could have been eaten by something else, but these mantids seem fairly formidable and I find it unlikely that three would get devoured overnight.
The remaining two adults have distinctive markings. In fact, the design on their wings is actually a mirror image of the other. I'll keep an eye on these two and the remaining nymphs.