German cockroaches

German CockroachesBlattella germanica (Linnaeus)

German Cockroach Identification

Color: Light brown to tan, with two dark, almost parallel stripes located on their backs, just behind their heads

Size: ½”-5/8” long

Legs: 6

Antennae: Yes

Shape: Oval

Region: Found throughout the United States

What is a German Cockroach? 

The German cockroach is the most common cockroach species found worldwide. While German cockroach infestations occur in a variety of human occupied spaces, they are most often associated with restaurants, food processing facilities, hotels, nursing homes and other institutional facilities. Keep reading to learn more facts and to get information on German cockroach control.

Common Behavior of German Cockroaches

German cockroaches show a preference for warm (70°F/21°C) and humid places. They are usually found in residential and commercial kitchens and secondarily in bathrooms. However, a German cockroach infestation can occur in any area where people eat and drink. In homes, this includes dining rooms, living rooms, dens and bedrooms. Any crack of crevice located near a source of food and/or water can harbor cockroaches. German cockroaches can fit through an opening as small as 3/8 inch in width.

German cockroaches are good hitchhikers and often find their way into new structures by hitching a ride in grocery bags, cardboard boxes, drink cartons and secondhand appliances such as refrigerators, televisions, microwaves, etc. They have been observed to migrate from building to building on warm evenings. Although uncommon, they can survive outdoors during the warm months.

German cockroaches have a wide palate. They will feed on almost anything with nutritional value including all kinds of food, as well as soap, glue and toothpaste.

Activity periods for German cockroaches vary greatly with life state, age and physiological state. For example, reproducing females are quite active, whereas males spend the majority of their time in harborage even at night.

Signs of a German Cockroach Infestation

German cockroaches prefer to live in warm, humid places close to food and moisture sources. They are frequently found in residential and commercial kitchen environments, and bathrooms, so these are the two most likely places for an infestation to occur. It is also likely to find German cockroach dropping in areas they frequent. Droppings may appear as small, dark, “pepper-like” material left on countertops or in drawers. There may also be fecal staining, which appears as dark spots or smears in the corners of rooms, along the tops of doors or around small cracks and openings into walls.

When German cockroach populations are present in large numbers, it may be possible to detect a mild, somewhat “musty” odor.