Why German cockroaches are a formidable foe, Part II

German cockroach feces and carcasses behind a fridge. Photo: Dr. Mohammed El Damir, BCE

Editor’s Note: In Part I of this series, Dr. El Damir explains the biology and behavior of German cockroaches. 

To effectively control German cockroach populations, it’s important to use an integrated pest management (IPM) approach that includes multiple control methods. Let’s start by exploring assessment. In fact, many industry experts are focusing more on “APM,” assessment-based management, to guide their decision-making for treatment and prevention.

Assessment involves regularly inspecting and monitor ing the area for signs of cockroach activity, such as fecal droppings, egg cases (oothecal), and live cockroaches. Gravid females with egg capsules or tiny nymphs are strong indicators of a German cockroach infestation. Since German cockroaches are not very mobile, it’s important to thoroughly inspect the surrounding area and move things around to locate the harborage site. Generally speaking, German cockroaches are small and fast-moving insects that are commonly found in kitchens and bathrooms. Here are some steps to inspect for German cockroaches:

1. 1. Look for droppings: German cockroaches leave small, dark droppings that resemble black pepper or coffee grounds. Check areas such as the back of drawers, cabinets and appliances.
   2. Look for live cockroaches: Use a flashlight to check for live cockroaches in areas where you have seen droppings or carcasses.
   3. Check for a musty odor: German cockroaches emit a musty odor that becomes stronger as the infestation grows. If you notice a strong, unpleasant odor in your kitchen or bathroom, it could be a sign of a German cockroach infestation.
   4. Use sticky traps: Place sticky traps in areas where you suspect there may be German cockroaches hiding or traveling. (i.e. behind the fridge, behind the stove, and inside sink cabinets). These traps will capture any cockroaches that walk across them, which can help confirm the presence of an infestation. Sticky traps can be used to monitor population size by counting the number of cockroaches caught in the trap over a certain period. This can help you track changes in the population and the effectiveness of your control measures. Regular monitoring can also help you detect new infestations before they become established and more difficult to control.