Rats and mice spell trouble year-round, but they are especially likely to invade in the fall and winter. Rodents that were living and breeding outdoors are looking for new food sources and protection from the weather, and our homes and businesses become prime targets for invasion.
They can get inside through amazingly small openings. If they can get their head through a hole, they can squeeze the rest of their body through as well. Incredibly, a young mouse can easily fit through a hole smaller than a dime, and a young rat can squeeze through a hole smaller than a quarter.
Both mice and rats are astonishingly good climbers, so they do not need to find openings near the ground. They can easily find their way onto roof tops where there may be gaps and openings of various sizes. Using their keen sense of smell, they sniff to find where air currents escaping from the building are warm, or smell of food, and they will try to enter at these points.
Rats can easily enlarge openings by gnawing their way through building materials. A persistent rat can even gnaw through hard substances like lead, aluminum, and mortar, though their first choice is to gnaw through softer materials. A rat jaw is amazingly strong—able to apply up to 8,000 pounds of pressure per square inch!
You can easily see why rats and mice frequently find their way indoors. Professional control is important because these pests carry diseases, can be difficult to control, and reproduce quickly.