German Cockroaches

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The German cockroach is the most common species of cockroaches infesting homes and businesses in our area and in most parts of the world

HOW DO I KNOW IF I HAVE GERMAN COCKROACHES?

  • As with other species, German cockroaches are mostly active at night, when they forage for food, water, and mates.

  • German cockroaches hide in cracks and crevices and other dark harborages that provide a warm and humid environment.

  • German cockroaches’ relatively wide, flat bodies enable them to move in and out of cracks and narrow openings with ease.

  • German cockroach feces may appear as small, dark, “pepper-like” material in the corners of rooms, around small cracks and openings, and on counter surfaces.

  • German cockroaches secrete an odor that may cause the area they are infesting to smell “musty”.

WHERE SHOULD I LOOK FOR GERMAN COCKROACHES?

Using a flashlight, check the following common hiding places for German cockroaches:

  • Cracks and Crevices of moist and warm areas

  • Behind and under refrigerators, stoves, microwaves, and toasters

  • Under tops of tables and in the corners, cracks and crevices of cabinets

  • Behind and under sinks

  • In the motor areas of refrigerators and soft drink dispensing machines

  • In switchboxes and electrical outlets

  • Under and behind cafeteria counters and soda fountains

  • In, beneath, and behind garbage and recycling bins

  • Anywhere else conditions are dark and moist

WHAT DO GERMAN COCKROACHES LOOK LIKE?

  • German cockroach adults are about ½” to 5/8” in length.

  • German cockroaches are light brown to tan except for pronounced parallel stripes along the pronotum (or head), sometimes extending the length of the body.

  • German cockroach nymphs go through a series of molts or “instars” in which their size and color will vary, but essentially they look like smaller versions of the adult and lack wings.

  • Although German cockroaches have fully developed wings, they do not fly.

The German cockroaches’ antennae are a little longer than the length of their body, and serve as powerful sensory devices for evaluating their environment, finding food and receiving messages from other roaches.

ARE GERMAN COCKROACHES DANGEROUS?

  • German cockroaches are known for their ability to transmit a number of pathogens, including E. coli, Salmonella spp. and Typhus. In fact, vomiting, fever, and diarrhea can often be traced to a roach problem.

  • German cockroaches feed and live in areas that harbor dangerous bacteria, such as sewers, garbage disposals, and dumpsters.

  • Food contamination can occur when German cockroaches carry bacteria on their bodies into food preparation areas.

  • Recent studies indicate that the allergens from the excrement and shed skin of cockroaches can trigger asthma attacks in children and individuals.

  • German cockroaches are capable of biting but rarely if ever do. Roach bites should not present a problem unless the bite gets infected.

HOW DID GERMAN COCKROACHES GET INSIDE MY HOME?

  • German cockroaches are excellent “hitchhikers.”

  • Typically, German cockroaches are brought into a new environment on paper products, cardboard boxes, grocery bags, used or 2nd hand appliances, and in rare cases in people’s clothes.

  • Rarely will German cockroaches migrate from building to building or be seen outdoors.

  • In apartments and other multi-housing buildings, German cockroaches may spread along utility lines, rubbish rooms, trash chutes, laundry rooms, storage areas, and other shared facilities.

  • German cockroaches are usually found in kitchens and bathrooms where they find heat and higher relative humidity. But they are not limited to these areas.

  • German cockroaches are also found in appliances such as radios, clocks, TV’s, phones, stoves, and refrigerators.

  • German cockroaches need food, water or moisture, heat and humidity, and shelter to survive.

WHAT DO GERMAN COCKROACHES EAT?

  • German cockroaches are mostly scavengers and will feed on any food source available, including crumbs missed during cleaning and dirty dishes left in the sink overnight, as well as starches, sweets, grease, meat products, almost any other human or pet food, garbage, toothpaste, soap and the bindings of books.

  • German cockroaches can survive without food for up to 30 days, but they will dehydrate if they are denied moisture for more than two weeks.

WHAT IS THE LIFECYCLE OF GERMAN COCKROACHES?

  • German cockroaches reach sexual maturity in a very short time and produce a large number of eggs, resulting in rapid population growth.

  • The German cockroach has three developmental stages: egg, nymph (several stages), and adult.

  • Female German cockroaches only need to mate once for the production of young.

  • Females produce a light brown, purse-shaped egg capsule (ootheca) that is less than ¼” in length and contains two rows of eggs.

  • Each capsule contains up to 30 to 48 eggs (average of 35), and an adult German cockroach female usually produces from four to eight egg capsules during her lifetime.

  • A significant number of German cockroach nymphs hatch successfully because the female carries the egg capsule on her back during the entire time the embryos are developing within the eggs.

  • When the time for the eggs to hatch is close, the female German cockroach deposits the egg capsule in a protected area, close to food, moisture, and suitable shelter.

  • It usually takes 28 days for the capsule to hatch from the time it begins to form.

  • German cockroaches produce an egg capsule about every 6 weeks.

  • German cockroaches mature through six to seven nymphal stages (instars) occurring over a period of 6 to 31 weeks.

  • There can be 3 to 4 generations of German cockroaches per year, depending on environmental conditions (heat/humidity, food, moisture, shelter, etc.).

  • The life span of the adult female German cockroach ranges from 20 to 30 weeks.

  • In one year over 10,000 descendants can be produced, assuming two generations per year.

2 INTERESTING FACTS ABOUT GERMAN COCKROACHES?

  1. Despite their name, German cockroaches are found all over the world.

  2. German cockroaches are not even originally from Germany. Many researchers believe they originated in Africa or Southeast Asia.