Roaches

Cockroaches are common pests throughout Hawaii. They can be carriers of human diseases and can be a leading cause of allergies, and thus should be controlled appropriately.

Identification of the roach is very important in that different species may require different treatments. There are 4 cockroach species in Hawaii that commonly infest households. These are: 1) the American Roach, 2) the Australian Roach, 3) the Brown-Banded Roach, and 4) the German Roach.

Roach eggs develop in a casing called the ootheca. The number of eggs per ootheca can vary from 8 to 60 depending on the species of roach. The female American or Australian roach may secure the ootheca to an appropriate surface upon formation, the Brown-Banded roach will drop its ootheca, or in the case of the German roach the ootheca is carried by the female until the eggs are ready to hatch.

Once hatched all roaches develop with gradual metamorphosis. They go through a series of molts (where they shed their exoskeleton) before reaching adulthood. This may take from 30 days to over a year depending on the species and environmental conditions. Most adult roaches are capable of flight which can make them extremely difficult to control.

Roaches are generally nocturnal. When seen during the day, this is usually a sign of a very large infestation.

Proper sanitation is one of the keys to control. Like any animal they require food, shelter and water to survive. Elimination or minimization of garbage, bits of food, soda containers, water supplies, etc. are essential to proper control.

The German roach is one of the most prolific roaches and can go from egg to adult in 30 days. This is half the time required for most other roaches. This very short breeding period also accounts for German roaches building up a resistance to certain pesticides. However, in theory it may be easier to control German roaches because they carry their ootheca until the eggs area ready to hatch. If a pesticide treatment for a German roach is effective the eggs protruding from her abdomen in the ootheca are likely to die off.

In other species the ootheca may be deposited on a surface which cannot be reached by the pesticide. The eggs may continue to hatch for more than 2 months. This time period may exceed the life of the pesticide and reapplication will likely be necessary.

German roaches generally prefer warm humid areas and will generally be found in kitchens and bathrooms. They prefer humid areas such as under sinks and warm places such as under the refrigerator where they can enjoy the warmth of the motor.

Brown-Banded roaches generally prefer warm dry areas and will therefore be found in upper locations such as behind pictures, wall hangings, etc. Brown-Banded infestations frequently are scattered throughout the structure. Because the infestation is widespread and the female carries the ootheca for a very short period of time, makes the Brown-Banded roach very difficult to control. Multiple treatments are normally required.

American and Australian roaches frequently breed outdoors due to the lower heat requirements but can also be found in basements and crawlspaces. These species may require indoor and outdoor treatments.