Within about two days after the egg case is produced, it is placed in a sheltered area that contains abundant food. In about two months, nymphs emerge and are most active from spring until midsummer. As with the brown-banded species, egg cases are susceptible to drying out, attack by fungus and cannibalism by other cockroaches, if other food is scarce. The egg cases are often eaten by other insects as well and, if in an accessible area, by birds. Behavior and Habitat.
Oriental cockroaches are less wary and more sluggish than other cockroaches found in Nebraska.
They are more sensitive to lack of water than other cockroaches and like cool, damp locations. Look for oriental cockroaches in dark, damp basements, crawl spaces, areas between soil and the foundation, underneath sidewalks, in sewer pipes, floor drains and any other cool, moist place. Outside, they sometimes aggregate near or under garbage cans. Inspections should concentrate in areas of high humidity and cool temperatures, as described above. In basements, infestations of these insects can sometimes be located by examining spider webs for evidence of oriental cockroaches.