Nest within structures or burrows. They enter buildings and homes in search of food. Some rats also have a preference for meats. Their litters consist of four to seven young, and they can live up to one year. Rats can have about four to seven litters a year, and the litters consist of two to seven young.
Rats are sexually mature at two to four months and live about one year.
Rats can fit through a whole the size of a quarter. Rats and mice carry many serious diseases.