Due to the large size and slow development of American cockroaches, large infestations of these insects are not common within households. However, during certain times of the year, these cockroaches may move inside a house from outside sources. For example, in winter these cockroaches may move indoors, seeking warmer temperatures and food. Cockroaches may enter houses via sewer connections, under doors, around utility pipes, air ducts, or other openings in the foundation. Cockroach populations in basements can be reduced by decreasing dampness and applying insecticides in cracks and crevices where there is evidence of cockroach activity (presence of egg cases, dead cockroaches, brown fecal smears).