House mice commonly weigh less than an ounce, so their movement behind walls and in attics can be too quiet to hear. In cases of large infestations, mouse noises are more noticeable. Homeowners may detect running or thumping sounds as the pests travel throughout the house. More apparent mouse sounds include gnawing, as the pests chew on wires or cords, as well as squealing when the rodents nest or scavenge for food.
