How many nymphs can a female German cockroach produce in a lifetime (how many eggs per sac x how many sacs)?
Ans: That number is not the usual number quoted and is (~40 x 5-6) = 200-240. In my substantial experience using B. germanica in my lab, a single female can produce at max about 5-6 egg cases during her lifetime, each about a month apart after her own approximate 35 day juvenile phase. The timing depends on temperature and they develop most quickly at 30C. Each egg case has approximately 40 eggs so that means a single female will only produce 240 primary offspring. However most people like to scare you with the calculation of total progeny. That means understanding that only half the 240 primary offspring are females who could each also have 240 offspring half of which are females. Depending on the temperature one needs to calculate the larger number of offspring that a female can produce in a year, which is the usual number that is quoted.
