German Cockroach

Have you ever wondered how one cockroach seems to turn into hundreds overnight? Making themselves nice and comfy inside of your home. Eating that tasty lasagna you left on the counter. Helping themselves to a cool refreshing drink from the leak under the kitchen sink. Then relaxing behind your refrigerator or in your drawers and cabinets.

This culprit is none other than the German cockroach. This cockroach has adapted to living in close proximity with humans and thrives in places where they have food, water, and harborage. With these three things they are able to infest a space quickly. Because of their ability to reproduce so fast one female and her offspring can create a population of over 30,000 cockroaches in one year. That is why this is a pest of major concern.

Below is a profile of the German cockroach and ways to prevent this pest from infesting your home or property.

Identification
  • Adults are ½ – ⅝ inch long, light brown in color and have 2 dark horizontal stripes behind their heads
  • Young resemble adults, but they don’t have wings
  • Eggs found in a capsule called an ootheca, which is reddish brown and about ¼ inch long
Behavior
  • The German cockroach is an omnivore and a scavenger.
  • They are commonly attracted to starch, sugary foods, grease and meat.
  • They will become cannibalistic at times as well.
  • German cockroaches are nocturnal, foraging at night and hiding in sheltered areas during the day.
Habitat
  • Live primarily in kitchens, bathrooms, and other humid places where they have daily access to water.
  • Prefer to hide in wood and paper material and because they are also attracted to warmth will harbor in electrical appliances.
  • Because of their flat shape, they are able to hide in cracks as small as 1/16th inch wide.
Life Cycle
(Gradual or Incomplete Metamorphosis)
  • Incomplete metamorphosis
  • The female produces an ootheca, an egg capsule less than a 1/4 inch long that contains 30-40 individual eggs.
  • The female cockroach carries the ootheca with her until the eggs are ready to hatch and then typically deposits them away from cockroaches to prevent cannibalism.
  • The eggs have an average incubation period of 28 days, although that does vary greatly.
  • Once the eggs have hatched, the juvenile German cockroach goes through 6-7 instars before they become an adult.
  • Once they become an adult, they typically live about 10 months.
Seasonality
Favorable Conditions
  • Clutter, including cardboard and paper
  • Humid places with a water source
  • Areas with many cracks and crevices that provide hiding places
  • Areas with poor sanitation that provide a food source
Health Concerns
  • Pose health concerns from bacteria cross contamination
  • Cockroaches can be a trigger for asthma.
  • People can also exhibit other allergic reactions to cockroaches including skin rashes, watery eyes, congestion of nasal passages and runny nose.
  • Cockroaches can also be a stressor or a source of anxiety or shame.
Signs of an Infestation
  • Live adult and young cockroaches
  • Droppings (frass) that look like ground pepper/coffee grounds on counters, in drawers and around cabinets
  • Fragments of dead cockroaches
  • Empty egg capsules

What You Can Do To Prevent a German Cockroach Infestation

  • Store food in tightly sealed containers to prevent food sources.
  • Fix all plumbing leaks to prevent sources of water.
  • Clean up food and drink spills and wipe down counters by the end of each day.
  • Inspect used furniture and appliances before you bring them into your home.
  • Seal exterior cracks and crevices of the home to prevent access.
  • Use weatherstripping around windows and doors to precent access.

What You Can Do When German Cockroaches Are Inside of Your Home

  • Use a vacuum with a HEPA filter to remove live cockroaches, cockroach fragments, egg capsules, and frass. Immediately remove the trash bag and place in an outside trash can.
  • Remove caked on droppings (frass) safely with soap and water and a scrub brush.
  • Install monitoring traps to capture cockroaches and monitor the population.
  • Use a 1:10 solution of soapy water as a contact killer. This approach is least toxic to you, your family, and the environment.
  • Seal cracks and crevices around cabinets, pipes, and baseboards that can provide harborage.