Pest ID: German Cockroach
Adults are about 1/2″ to 5/8″ (13 – 16 mm) long. Color light brown to tan except for 2 dark, almost parallel longitudinal stripes/bars/streaks on the pronotal shield. Check out the German Cockroach picture on the page. Female darker than male with a broader abdomen. Winged, but rarely glide or fly. Nymphs are dark brown to black having pale lateral margins. Egg capsules are yellowish brown but usually two toned, paler and attached to the female.
Places Most Commonly Found:
German cockroaches are found throughout structures but show a preference for warm (71 F/21 C) and humid places. They are usually found in kitchens and secondarily in bathrooms, but infestations often occur in rooms where people eat and drink while watching television, such as the den, bedroom, etc. Any crack or crevice near a food or water source is prime harborage and they spend about 75% of their time in such harborages. These cockroaches are most commonly introduced to a structure via paper products or packaging such as grocery bags, cardboard boxes, drink cartons and via secondhand appliances such as refrigerators, televisions, microwaves, etc. They have been observed to migrate from building to building on warm evenings but this rarely occurs. Reproducing females are highly active, but females with an egg case are rarely active and will seek food and water only when necessary.
Most Active Period:
Infestations can occur any time during the year. Rate of increase in population is directly proportionate to food and harborage conditions. Each female will produce about 5 egg cases (oothecae)(range 4 -8) averaging 30 to 40 eggs per case (range 18 – 50 each). Development time (egg to adult) usually varies from 51 to 215 days. Under ideal conditions of 80 F/27 C and 40% relative humidity only 50 to 60 days are required. This can result in 3 to 6 generations per year. Established German cockroach populations are typically composed of 75% nymphs.
Difficulty of Control:
Difficult to control if sanitation issues are not addressed. Moderate to control if sanitation is not an issue.