The oriental cockroach tends to travel somewhat more slowly than other species. They are often called "waterbugs" since they prefer dark, moist places. They can often be found around decaying organic matter, and in sewers, drains, damp basements, porches, and other damp locations. They can be found outside in bushes, under leaf groundcover, under mulch, and around other damp places outdoors. They are major household pests in parts of the northwest, mid-west, and southern United States.
In order to thrive, cockroaches need a place to hide. They prefer warm places and a relatively high humidity if possible; they also need a source of food/liquid. The optimum temperature for oriental cockroaches is between 20 °C (68 °F) to 29 °C (84 °F). Female oriental cockroaches have vestigial tegmina (reduced forewings) and males have longer tegmina. Cockroaches are mainly nocturnal. Oriental cockroaches can be elusive in that a casual inspection of an infested dwelling during the day may show no signs of roach activity.
Signs of cockroaches are their oothacae, which are “egg cases” containing up to 16 individual eggs in the case of oriental cockroaches. These oothecae are dropped by females and hatch on their own in about two months. Oriental cockroaches can be harder to get rid of than other roaches. Although adults can be fairly easily killed by the application of residual insecticide, the insecticides can get washed away, and two months later females can hatch new nymphs.