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  • Writer's pictureJon Stoddard

Comprehensive Guide To German Cockroaches: With Pictures and Videos


Blattella germanica german cockroach

The German cockroach (Blattella germanica), sometimes known as the croton bug, is a species of tiny cockroach, typically measuring between 1.1 and 1.6 centimeters (0.43 and 0.63 inches). Its hue ranges from brown to nearly black, and its pronotum has two dark, relatively parallel stripes that run from behind the head to the base of the wings. Although B. germanica has wings, it is unable to fly and can only glide when agitated. This one is likely the most problematic among the few kinds of cockroaches that are considered household pests. It is closely related to the Asian cockroach, and to the untrained eye, the two species appear almost identical and may be confused. Unlike the German cockroach, the Asian cockroach is drawn to light and may fly like a moth.


German Cockroach Biology and status as a pest


Blattella germanica german cockroach

The German cockroach is widespread in human structures but is especially common in restaurants, food processing industries, hotels, and institutions such as nursing homes and hospitals.

They can also survive in the wild, though rarely seen there. In cold areas, they are only found in close proximity to human dwellings, as they cannot endure extreme cold. Nonetheless, German cockroaches inhabit human structures as far north as Alert, Nunavut. Similarly, they have been discovered in southern Patagonia. Formerly believed to have originated in Europe, the German cockroach was later believed to have originated in the Ethiopian region of northeastern Africa. Still, more recent research indicates that it originated in Southeast Asia.

Regardless, the cockroach's sensitivity to cold could result from its genesis in such warm climates. Since antiquity, its proliferation as a household nuisance has resulted from accidental human transfer and refuge. The species is now worldwide, existing as a domestic nuisance on all continents except Antarctica and on numerous significant islands. Thus, it has diverse names in the cultures of numerous regions.


While nocturnal, the German cockroach occasionally appears during the day, especially when the population is dense or agitated. However, most sightings occur in the evening, when the light is abruptly turned on in a dark space, such as a kitchen where they have been foraging. This species has a foul odor when agitated or frightened.


German Cockroach Diet


Blattella germanica german cockroach feeding

Cockroaches from Germany are voracious scavengers. They are particularly drawn to meats, carbohydrates, sweets, and fatty foods. They may consume household products such as soap, glue, and toothpaste when food is scarce. In times of scarcity, they become cannibalistic and consume each other's wings and legs. Moniliformis kalahariensis, an Acanthocephalan parasite, uses the German cockroach as an intermediate host.


Reproduction of German Cockroaches


Cockroaches Life Cycle object vector on white background.

The German cockroach reproduces more rapidly than any other residential cockroach, maturing from egg to reproductive adult in approximately 50 to 60 days under optimal conditions.

A female German cockroach develops an egg capsule called an ootheca in her abdomen after being fertilized. The abdomen swells as the eggs develop until the fine tip of the ootheca begins to protrude from the end of her abdomen. The eggs are fully developed, measuring around 1/16 of an inch long and containing 16 segments. The ootheca, which is initially translucent, turns white and then pink after a few hours, gradually darkening until, 48 hours later, it attains the color of a chestnut's shell. The egg capsule/ootheca has a keel-like ridge along the ootheca line where the young emerge, and as it matures, it coils slightly towards this edge. A limited number of nymphs may hatch while the ootheca is still linked to the female, but most emerge 24 hours after the ootheca has separated from the female's body. The newly hatched, 3-mm-long black nymphs undergo six or seven instars before achieving sexual maturity; nevertheless, ecdysis is such a risky process that approximately half of the nymphs perish due to natural reasons before reaching adulthood. Molted skins and deceased nymphs are quickly consumed by living nymphs during molting.

Pest control for German Cockroaches


The German cockroach is highly effective at establishing an ecological niche in buildings and is resistant to numerous pest-control methods. Pest Control Examples include but are not limed to:


German Cockroaches lack natural predators in human habitats, which results in abundant reproduction and a brief reproductive cycle.

The capacity to conceal in very small refuges, sexual maturity acquired in weeks, and adaptation and tolerance to certain chemical pesticides.


German cockroaches are thigmotactic, which means they favor enclosed places. German Cockroaches are small compared to other pest species, so they may hide in little cracks and crevices that are easy to miss, avoiding humans and their eradication efforts. In contrast, an experienced pest controller is vigilant for gaps and crevices where placing baits or spraying surfaces is likely to be profitable.


To be effective, control techniques must be comprehensive, long-lasting, and systematic; the survival of a few eggs is sufficient to rebuild a nearly extinct German Cockroach pest population within a few generations, and recolonization from neighboring populations is frequently rapid as well.


The population behavior of German cockroaches is another obstacle to their control. Although they are not sociable and do not perform organized maternal care, females hold oothecae containing 18 to 50 eggs (on average about 32) during incubation until just before hatching, unlike the majority of other cockroach species. This safeguards the eggs from specific types of predators. After hatching, nymphs survive mostly by devouring the excretions and molts of adults, forming their own internal microbial populations. They are adept at avoiding contact with most pesticide surface treatments and baits. Insect growth regulators (hydroprene, methoprene, etc.) are an efficient method of control because they impede molting and, consequently, the maturity of the various instars. Caulking baseboards and around pipes can prevent adults from moving between apartments inside a building.


German female cockroach ootheca


Macro photo of an adult red cockroach lying on its  bag with ootheca laying next to the dead body

As an adaptive response to the use of poisoned sugar baits for pest control, a type of German cockroach has evolved to find glucose unpalatable. They refuse to consume sweetened baits, which hinders their control, given that baits are a cost-effective and affordable method. In the absence of poisoned sweet baits, attraction to sugars significantly boosts growth, energy, and reproduction; cockroaches that are not drawn to sugars develop and reproduce more slowly, yet in the presence of poisoned sugared baits, sugar avoidance promotes reproduction.


German Cockroach Quick Facts

Size: 13–16 mm (0.51–0.63 in) (0.51–0.63 in)


Favorable temperature:

15–35 °C (59–95 °F)


Nymphal development:

54–215 days \s(at 24–35 °C (75–95 °F)


Lifespan:

Around 200 days


The ability of Flight:

Uncommon


FAQs on German Cockroaches


FAQ sign


What is a German cockroach?

The German cockroach (Blattella germanica) is a small species of cockroach widely considered a pest. It is the most common species found in urban environments around the world. These insects are typically between 1/2 to 5/8 inches long, with a light brown or tan color and two parallel, dark stripes on their pronotum (the shield-like structure behind their head).

What attracts German cockroaches to a home or building?

German cockroaches are attracted to food sources, warmth, and moisture. Typical attractions include unsealed or improperly stored food, dirty dishes, and trash. They also seek out places with high humidity, such as leaky pipes, damp basements, and bathrooms. Follow these tips to keep german cockroaches out of your home.


How do German cockroaches reproduce?

German cockroaches reproduce rapidly through a process called ovoviviparity. Females carry an egg capsule called an ootheca, which contains approximately 30-40 eggs. The female carries the ootheca until the eggs are ready to hatch, typically after about 3-4 weeks. Once hatched, nymphs undergo several molts over 6-12 weeks before adulthood. Due to their fast reproductive rate, infestations can proliferate if left untreated.

While German cockroaches do not bite or sting, they can still pose health risks to humans. They have known carriers of various pathogens, such as Salmonella, E. coli, and other bacteria, which can lead to food poisoning or gastrointestinal illnesses. In addition, their shed skin and feces can trigger asthma and allergy symptoms in sensitive individuals.

How can I prevent a German cockroach infestation?

Preventing a German cockroach infestation involves maintaining a clean and sanitary living environment. Take the following pest-proof steps to minimize the risk of an infestation:

  • Store food in airtight containers

  • Clean up spills and crumbs promptly.

  • Regularly remove trash from the premises.

  • Seal cracks and crevices in walls, baseboards, and cabinets

  • Fix leaky pipes and ensure proper ventilation in bathrooms and basements.

  • Regularly vacuum and clean floors, countertops, and appliances

How can I eliminate a German cockroach infestation?

Eliminating a German cockroach infestation can be challenging due to its rapid reproduction and ability to hide in small spaces. The following methods can be used to control an infestation:

  • Use bait stations containing insecticides to target both adults and nymphs.

  • Apply insecticidal dust in cracks and crevices where cockroaches may be hiding.

  • Utilize glue traps to monitor and capture cockroaches.

  • Employ a professional pest control service for severe infestations.

Are there any natural methods to control German cockroaches?

While natural methods may be less effective than chemical treatments, they can still be used as part of an integrated pest management strategy. Some natural methods include:

  • Diatomaceous earth: A non-toxic powder that can be applied in areas where cockroaches are found, damaging their exoskeletons and causing them to dehydrate

  • Boric acid: A low-toxicity substance that can be used as bait or applied as dust in areas where cockroaches are present

  • Essential oils: Some essential oils, such as peppermint, eucalyptus, and tea tree oil, may repel or kill cockroaches when applied in high concentrations.

  • Sticky traps: Use these to capture cockroaches and monitor the infestation

Natural methods may not be sufficient to eliminate a severe infestation.


Can German cockroaches develop resistance to insecticides?

Yes, German cockroaches have developed resistance to certain insecticides over time. This is due to their rapid reproduction rate, allowing them to evolve and adapt quickly to various control methods. To minimize the development of resistance, it is essential to use multiple control strategies, such as combining chemical treatments with sanitation and exclusion techniques.


How can I identify a German cockroach infestation?

Some signs of a German cockroach infestation include:

  • Live or dead cockroaches: Seeing live or dead cockroaches around your home or building indicates an infestation.

  • Droppings: German cockroach droppings resemble black pepper or coffee grounds and are commonly found in areas where they feed or hide.

  • Egg capsules: These brown, oblong capsules (oothecae) may be found hidden in areas such as behind appliances, in cabinets, or under sinks.

  • Unpleasant odor: A musty, oily smell can be associated with a significant infestation.

  • Shed skins: As nymphs grow, they molt and leave behind their exoskeletons. Finding these shed skins is another indication of an infestation.

Can German cockroaches fly?

While German cockroaches have wings, they are not strong fliers. They primarily rely on their legs for rapid movement and are likelier to run or scuttle than fly. In rare cases, they may use their wings to glide short distances, but there are other modes of transportation.


How can I differentiate German cockroaches from other cockroach species?

Key characteristics to differentiate German cockroaches from other species include:

  • Size: German cockroaches are smaller than many other species, measuring between 1/2 to 5/8 inches in length.

  • Color: They have a light brown or tan coloration, making them lighter than many other species.

  • Pronotum markings: German cockroaches have two parallel, dark stripes on their pronotum, which is a distinguishing feature.

Can German cockroaches survive cold temperatures?

German cockroaches are not well-adapted to cold temperatures and typically thrive in warm, humid environments. However, they can survive and continue reproducing in cooler temperatures, provided they can access food and shelter. They are more likely to be found indoors in colder climates, seeking refuge in heated buildings.


Are there any predators that can help control German cockroaches?

Some natural predators of German cockroaches include spiders, centipedes, and certain types of beetles. While these predators can help control cockroach populations to some extent, they are typically insufficient to eradicate a severe infestation. A comprehensive pest management plan is necessary to address a German cockroach infestation effectively.

Maintaining a clean and sanitary living environment is crucial for preventing and controlling German cockroach infestations. Combining chemical treatments, natural methods, and good sanitation practices will yield the best results in eliminating these pests.


Professional German Cockroach Infestation Treatment Company


Imperial Pest Prevention, located in Daytona Beach, Florida, is a highly experienced pest control company that handles German cockroach infestations. Our approach is based on a comprehensive and effective treatment plan that includes chemical and non-chemical pest control methods to eliminate the infestation and prevent future outbreaks.


The first step in our treatment plan is a thorough inspection of the affected area to identify the extent of the infestation and the areas where the cockroaches are likely to hide. Based on our findings, we create a customized german cockroach treatment plan tailored to the client's specific needs.


The treatment plan may include using insecticides, baits, and traps to kill the cockroaches and prevent their reproduction. In addition, we may also recommend non-chemical methods, such as sanitation and exclusion, to eliminate food and water sources and prevent cockroaches from entering the premises in the first place.


Imperial Pest Prevention also provides follow-up services to ensure the infestation has been completely eradicated and to prevent future outbreaks. We offer regular inspections and treatments to ensure that the cockroaches do not return, and we also provide valuable advice on how to prevent infestations from occurring in the future.


Overall, Imperial Pest Prevention is a reliable and effective choice for handling German cockroach infestations in Daytona Beach, Florida, and surrounding areas. Our comprehensive and customized treatment plans, expertise, and experience make us a top choice for anyone dealing with a cockroach infestation. Contact Imperial Pest Prevention today if you suffer from German cockroaches. Once you employ our German cockroach pest control services, be sure to follow our cockroach pest control service preparation video.



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