Oriental Cockroaches

Facts

General Information

orientalAlso known as black beetles or water bugs, Oriental cockroaches are common in the Northern United States. The Oriental cockroach, scientifically classified as Blatta orientalis, is an immigrant species thought to have originated in Northern or Sub-Saharan Africa. Despite their warm-weather origins, Oriental cockroaches survive in colder areas due to their ability to overwinter outdoors and withstand freezing temperatures. Oriental cockroaches also infest homes, creating problems ranging from unpleasant nuisances or odors to serious health complications.

Appearance & Identification

What do Oriental Cockroaches Look Like?

oriental roach
Oriental Cockroach

Photo source:Univ of Nebraska Lincoln

oriental roach outside
source: OSU
dead oriental roach with ruler
source: OSU

Body
Oriental cockroaches are sometimes called black beetle cockroaches due to their shiny black bodies.

Size
Oriental cockroaches are roughly an inch in length and are the second largest common cockroach (American cockroach is larger).

Legs
Like all species of cockroaches common to the region, the Oriental variety boasts six spiny legs and a pair of long, slender antennae.

Wings
The sex of Oriental cockroaches determines whether the insects have wings; males feature a short pair of wings covering most of the abdomen, while females remain wingless. Despite having wings, male specimens are not known to fly.

Habitat

Where Do They Live?

Inside
Water bug” is the other common name for Oriental cockroaches, comes from the tendency of the insects to enter homes and buildings through drains and pipes. Once inside, Oriental cockroaches typically occupy damp, dark areas such as basements and crawl spaces. The insects rarely venture to the upper levels of buildings with multiple floors.

Outside
Highly adaptable, Oriental cockroaches can also live outdoors in places like cisterns, dumpsters, sewers, and piles of firewood, leaves, or mulch. They hide under woodpiles and trashcans. They live under sheds and doghouses. They also live under ivy and ground cover. They even hide in drains and water meter boxes.

Diet

What do Oriental Cockroaches Eat?
Oriental cockroaches eat a wide variety of food sources but prefer to feed on starches and decaying organic material. Oriental cockroaches are often seen foraging in garbage cans and other discarded containers used to store food. Oriental cockroaches need water to live and, with a regularly available water source, can survive for up to a month without consuming any food. If removed from a constant water source, Oriental cockroaches generally die within a couple weeks.

Reproduction

Like other cockroach species, Oriental cockroaches hatch from eggs and emerge as nymphs before fully maturing into adults. Adult females produce up to 16 eggs at a time in a protective capsule or egg case, which is deposited on or near a shielded food source. At room temperature, the eggs hatch in roughly two months. Newly hatched Oriental cockroaches live as nymphs for six months to two and a half years. While nymphs grow and develop, they typically molt, or shed their skin, seven to 10 times.

How Long Do They Live?
After developing into adults, Oriental cockroaches usually live for six to twelve months, with females producing an average of roughly 200 eggs in adulthood.

Read more about the life cycles of cockroaches.

Problems Caused by Oriental Cockroaches

They Smell Bad!
Notorious for giving off a pungent and unpleasant odor, Oriental cockroaches also unwittingly spread hazardous bacteria picked up from the unsanitary surfaces on which the insects crawl.

Can Live in Sewage
Oriental cockroaches regularly live in and crawl through sewage and other filth containing disease-causing organisms. When the insects infest homes and other occupied buildings, they frequently transfer the bacteria and viruses from their legs to food, dishes and utensils, countertops, and other objects used and consumed by humans.

Spread Disease
The most common diseases spread by Oriental cockroaches include dysentery and food poisoning.

Control

Controlling the members of the oriental cockroach family starts outside. Place firewood on a rack and move it away from the building. Rake mulch and leaves away from the foundation. Clean the gutters and make sure down spouts drain away from the foundation.

Granular cockroach bait is an effective tool against these pests. Many brands of bait are water-resistant. They can be used effectively in flowerbeds and ground cover. The bait will have to be applied any time the roaches are active.

A barrier of liquid insecticide is also effective. It helps prevent the roaches from gathering near the foundation. Since sun and rain break down insecticide, the barrier will have to be re-applied periodically.

Rather than fight these cockroaches themselves, many homeowners prefer to get a pest control professional to apply the bait and the insecticide.

How You Can Get Rid of Cockroaches.