House mice are small and can enter buildings through openings very small. Due to their small size, they may also be carried into buildings in merchandise or in items that have been in storage. The house mouse is adaptable and can survive in outdoor situations as well as within buildings. Mice are not alarmed when new items appear in their territory. In fact, they readily explore new items.
Mice feed as nibblers.
Mice are territorial and may move within 20-foot radius, with the nest area being the focal point. The common commensal rats, Norway and roof rat, have different body characteristics as well as some behavioral differences - see figure two for the body differences. Either rat can be found within buildings, near food storage or preparation. How they enter buildings is a different matter. The roof rat, on the other hand, enters buildings from elevated points such as overhanging tree limbs or utility lines.