Common Name: German Cockroach
Name: Blattella Germanica
About The German Cockroach
The German Cockroach is one of the smaller species of cockroaches, and is the most common cockroach found in Canada. The German Cockroach ranges from about 0.15cm to 2.25cm in length depending on its growth stage. The Brown Banded Cockroach is another small cockroach that is occasionally found in Canada, but is far less common than the German Cockroach. We are also starting to see more of the larger cockroaches such as the American Cockroaches, and Oriental Cockroaches pop up from time to time.
The German Cockroach is primarily an indoor pest in Canada. Due to our climate, as well as robust bird populations, the German Cockroach can’t survive very long outside. These small cockroaches manage to spread out by hitching rides into our homes by way of infested groceries (mainly bulk produce), personal items, or infested appliances and furniture that are brought into the house.
The German Cockroach is considered to be nocturnal, but it is not uncommon to see them during the day, especially if they are disturbed, or if the population is quite large. However, the numbers that you will see moving about during the day will only represent a very small percentage of the total population living in your home. Most of their scavenging, mating, and traveling is conducted at night under the cover of darkness.
As omnivorous scavengers, German Cockroaches will eat pretty much anything. However, much like us, they are quite attracted to sugars, starches and fats. Also like us, they will broaden their tastes when the food supply is low. Cockroaches will often feed on their own dead, as well as their own feces in order to survive.
Once in your home, German Cockroaches are going to be attracted to areas that are warm, and relatively humid, giving preference to places with lots of dark cracks and crevices to hide in and also in close proximity to a food source. This makes kitchens and bathrooms perfect spots to settle in. The German Cockroach is not a social species at all. They exhibit no signs of any sort of social structure in the way that they scavenge for food, behave toward one another, or raise their young. However, they are often found living together in large clusters sharing shelter. This is probably due, at least in some way, to their genetics. German Cockroaches possess an exceptionally large number of chemoreceptors known as the ionotropic receptors. It is through these receptors that the German Cockroach is able to detect a wide variety of chemical cues including food sources, bacteria and pathogens, toxins, and pheromones. It is thought that the German Cockroach may release a special pheromone. This pheromone is likely what attracts other cockroaches to share the same harbourage spots. It’s not certain exactly why they seem to follow this pheromone. It could simply be for survival, ensuring mating opportunities among an otherwise solitary species. it was once thought that it may be a “safe harbourage” pheromone released to indicate when a cockroach finds a safe place to stay. However, this pheromone following behaviour also appears to attract cockroaches to places of danger as well. This we see regularly in the field when setting out glue boards to use as monitors. Once more than one cockroach is captured on the sticky monitor, the number of new captures on that monitor appears to increase exponentially after that.
The ability to detect a wide variety of chemical cues also makes the German Cockroach acutely aware of toxins. This is why you should never spray for cockroaches. The spray may kill the few cockroaches that it contacted, but the smell of the spray will cause many more cockroaches to run, or hide. This can cause cockroach populations to divide and spread out into new areas where they would otherwise not be interested in going such as living rooms, and bedrooms. Once a cockroach population has divided and spread out like this, it can prolong the time it takes to resolve the situation by several weeks or even months. This is partially due to how spread out they can become, but also because the best way to eradicate cockroaches is by way of an edible bait which delivers poison or an IGR (insect growth regulator). And, if a chemical spray has been used in the area, that chemical can taint the bait causing the cockroaches to avoid it.
In short, spraying for cockroaches is one of the worst things that you can do!
German Cockroaches can reproduce very quickly. It only takes about 7-10 weeks for a newly hatched nymph to reach sexual maturity. The fertilized female will carry her egg case, (ootheca) containing 16-50 eggs, with her until just before they hatch.
How To Get Rid of Cockroaches
If you have cockroaches in your home or business, the best thing that you can do is to call in a cockroach specialist right from the start. Almost all pest control companies will treat for cockroaches, but not all pest control companies are cockroach specialists. Always do your homework.
If you call in a specialist quickly to take care of cockroaches, before trying to get rid of them yourself, then the process is likely to take no more than a couple of weeks and may cost a couple hundred dollars, in the end. However, if you wait too long, if the cockroaches have become well established, or if you have tried to treat the cockroaches yourself, then the process can take up to a year, and may cost several times that.
How To Prevent Cockroaches
Cockroaches are fairly easy to prevent. If you live in a single dwelling home, then all you really have to do, is be very careful to examine everything that comes into the house. Being mostly concerned with bulk or import foods as well as used clothing or furniture.
If you live in a multi-family structure such as an apartment building, duplex, four-plex, townhouse, or condo complex, then you may also want to take some time to make sure that your unit is sealed from all other areas of the building. This can include sealing holes around all plumbing, HVAC, and electrical lines coming into your unit, as well as ensuring that all doors have adequate weather stripping, thresholds and sweeps installed. In addition, you also want to use caution when using, or setting personal items down in, common spaces such as hallways, laundry rooms, storage areas and garbage rooms.
Early detection can prevent a lot of costly treatments. Sticky, insect monitors are one of the best items to use for early detection. You can place one or two in your kitchen, under the sink, in the pantry, or behind the stove, and check them every month for signs of insect activity. This also allows you to provide a sample for positive identification if you call in a professional.