American, German, Oriental, and brown-banded cockroaches are indoor pests that can be found throughout the United States, including Maine. German cockroaches are responsible for virtually every cockroach infestation that occurs within residential homes in Maine, and this species is notable for dwelling solely within indoor environments. German cockroaches are around ½ inch in length, similar to the brown-banded cockroach, which is the only other domestic cockroach species in the US. Unlike brown-banded cockroaches, German cockroaches have two vertical light brown stripes running down their dark brown back, making them easy to identify.

German cockroaches reproduce rapidly within wall voids and other dark and well concealed indoor areas, and at night, a small number of adults emerge from their hiding spots to gather food sources. Amazingly, one German cockroach female can reproduce 40 million offspring during her 2 year lifespan. Given their filthy living habits that involve the mutual consumption of feces, German cockroaches are known to contaminate stored foods with numerous pathogens, including E. coli and Salmonella. It is now understood that both live and dead German cockroaches are a significant source of indoor allergens that sensitize individuals to asthmatic conditions. Although German cockroaches are resistant to insecticides and experts believe that they are far too crafty to ever be eradicated from indoor environments, a recent study has revealed that simply improving indoor air circulation can make homes largely unlivable for cockroach pests.

Not long ago, Dr. Richard J. Brenner, a research entomologist, and a team of colleagues constructed a mock house in order to observe where German cockroaches congregate and to determine the environmental conditions they need to thrive. The study clearly showed that air flow from indoor ventilation serves as the most effective German cockroach repellent. Just a slight draft is enough to fatally dessicate, or dry out, a cockroach, which is part of why they remain within wall voids where air flow is almost nonexistent. Improving ventilation in existing homes can make the indoor environment deadly to cockroaches, and by designing new homes to be ventilated in all areas, including cabinets, may end the German cockroaches’ days as a cohabitant of homes and buildings.

Have you ever heard cockroach activity within your walls?