Which rodent typically has five litters per year?

The Norway rat is known for its high reproductive potential, typically producing around five litters per year. This reproductive rate allows the population of Norway rats to grow rapidly, which can lead to significant infestations if left unchecked. A single female can produce numerous offspring, and under ideal conditions, the population can escalate quickly.

In contrast, other rodents may have different reproductive patterns or fewer litter frequencies. For example, the house mouse and roof rat may have three to six litters per year, but it's more common for them to average around five to six with a variable number of litters in some conditions. The wood rat generally has a lower reproductive rate compared to the Norway rat and may not reach the same prolific breeding levels. This distinct breeding characteristic of the Norway rat contributes to its status as a common pest in urban areas, where it can cause various structural and health-related issues.