I feel like the bacteria could live longer if it was more intelligent about where it found its food. I.e, I think the population count plateaus and falls too soon when there is still enough food for growth.
That said, I know absolutely nothing about biology so maybe I am wrong.
I think the thing you are missing is that bacteria do not have brains. On that note is the "AI" just random direction for random amount of time or is it more complex? Also, out of interest how come some bacteria dropped 2*2 square of food on death and some dropped 3*3 square?
Anyway lovely to watch.