I have noticed over the last year that Phoetalia pallida, int. al. have a tendency to control their population to a point where they stop breeding totally, when the populations reach a certain point, regardless of food or heating levels.

My research is ongoing, and I will try to ascertain the optimal levels for maximum breeding increase in the next few months.

I presume this is the same in other species. Does anyone have specifics, perhaps?

I've seen colonies discontinue breeding with overcrowding but the cause has always been food, cannibalism and stress rather than some innate sense of self control associated with too little elbow room.

This is interesting- I've noticed quite the opposite in most of my B. craniifer populations- I've actually gone to the length of separating all new males and new females from the rest of the groups to stop any new generations from being bred as the population has simply become enormous.

Huntsman mentions Temperature, which in my experience should be added to Orins list. There is a correlation between temperature and metabolism/breeding until the roaches get to a point that they stop eating and all other life processes. It all happens within relatively few degrees.
So for Bricktop, temperature could be used as another mean to slow down speed somewhat? Have you tried that? Maybe just a few degrees.
Huntsman, are you sure that temperature should not be a part of your observations? Have you looked for abortions of the oothecas? Are the oothecas fertile when produced?

BR/
Ole