How strong is the reproductive capacity of rodents?

The reproductive capacity of rodents can be described as a geometric explosion.

Female Norway rats reach sexual maturity at 3–4 months of age, have a gestation period of about 21–23 days, produce litters of 6–12 pups, and can breed 4–7 litters per year; the offspring of a single pair of Norway rats can reach 1,000–2,000 after one year.

The reproductive rate of the house mouse is even faster — females reach sexual maturity at 6–8 weeks of age and can breed 5–10 litters per year.

In real environments, predation and disease keep populations within certain limits.

But a rule of thumb is: for every rodent you see, there are at least 5–10 more you do not see.

If rodents are seen during the daytime (rodents are nocturnal), it indicates that the population density is already very high.