No one wants to find a big black cockroach-looking bug menacing their home or business. Especially when there might be more of them, or even a hidden infestation.
But knowledge is power, every cockroach problem can be solved, and this one is pretty clear.
Ready? It’s time to learn about the big black roach you found, and how to make it disappear.
A Simple 5-Step Guide For Getting Rid of Roaches
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First Things First: A Few Black Bugs That Look Similar to Roaches (But Aren’t)
Before putting the cockroach before the cart, let’s eliminate a few bugs that look sort of like black cockroaches, but really aren’t.
- Black Carpet Beetles. Similar in size to a black roach nymph, these small black insects do resemble roaches. But unlike a roach, their shells are rounded (as opposed to a roach’s somewhat flattened body) and are visibly thicker. Their antennae are also shorter than a roach’s, and unlike the antennae of a roach, flare out at the ends.
- Black Ground Beetles. Also black in color, but larger than carpet beetles, ground beetles look sort of like black roaches, but have squatter, rounded bodies, shorter antennae, and thick, un-cockroach-like protruding jaws.
- Black Field Crickets. These insects grow to about the same size as a nymph (or baby) black cockroach. But their hind legs are longer and more powerfully built than those of any roach. You’ll never see a cockroach hopping, so if the one you’ve spotted does it, you can be pretty sure it’s just a cricket.
Luckily (or not so), if the bug you’ve found is indeed a cockroach, the number of possible candidates are few. The most likely culprit is a pest that invades homes across the United States and Canada: it’s called Blatta orientalis Linnaeus – the Oriental cockroach.
Understanding the Oriental Cockroach
Identification
Unlike other household roaches which tend to be tan, light brown, or reddish-brown in color, Oriental roaches are a deeper, darker brown that looks more like a shiny black..
3/4 inches to 1 inch in length and oval-shaped, they have segmented, glossy bodies, long antennae, short spiny legs, and a pair of appendages at the bottom of their bodies called cerci.
Males and females look somewhat different, based mostly on the length and structure of their wings. The adult male has short translucent wings that cover only a portion of its back.
The adult female Oriental has wings also, but they’re even shorter, less developed than the males, and blend in with the rest of their bodies. The female’s wings are so inconspicuous that unless you’re actually looking for them, you might miss them altogether.
Habitat
Oriental roaches are choosy about where they live and breed. They need lots of moisture to survive, so habitats that support them need to be humid and provide access to sources of water.
For you this means identifying dark, damp areas around your home to note and work with later.
Kitchen cabinets provide lots of suitable nooks and crannies, but the cabinets under sinks are especially attractive. Even a few drips from a sink pipe can be a black cockroach’s water source.
Speaking of pipes, these bugs have no qualms about crawling through them to move around a building. Both sink drains and outdoor drainpipes can give them access to virtually any room or space–no key or invitation required.
Which is one of the reasons they’re such notorious apartment pests. If they get into an apartment building, nursing home, or office building, they can easily spread from unit to unit by traveling through the pipes.
Crawl spaces and basements provide ideal spaces for them. These are often the dampest, least-visited area of a home, and offer black cockroaches a chance to live and reproduce in peace.
Outsides, like several other outdoor cockroach species, they’ll live anywhere that’s dark and damp, including mulch, bushes, your garage, the void below your porch and more. They’ll even live under tree roots or sections of paths and sidewalks.
Reproduction
Understanding how the black roach reproduces gives you insight into how and where they spread.
Females produce protective egg capsules which they hide in dark, humid areas near food sources. Each of the eight egg cases she’s capable of producing over her lifetime contains about 16 eggs – so even a few roaches can multiply quickly.
While finding adult roaches can be difficult, finding their carefully hidden oothecae (the egg cases) is even harder. Less than 1/2 inch long and well-camouflaged, Oriental roaches hide them in crevices or dark, out-of-reach places. After about 42-81 days, the eggs hatch into nymphs that will grow for up to a year before reaching adulthood and reproducing themselves.
Food
The diet of an Oriental roach isn’t exactly limiting.
It will eat virtually anything that ever was, or is alive–decaying plants, dead insects, sewage and more.
Your crumbs, garbage, compost, and every bit of decaying organic matter in your yard or garden are fit for a cockroach buffet. They’re particularly fond of starchy foods (like cereal and bread), and will eat the starches in book bindings and cardboard, too.
How to Get Rid of Them
As you prepare to deal with the Oriental roach, realize that you’re dealing with resourceful pests. They come from harsh places you might never have considered: sewers, drains, gutters and more.
So they’re used to surviving difficult conditions and evading situations that could potentially cause them harm. Grabbing a can of bug spray may kill one or two of them, but won’t do anything to kill the others that are hiding.
You’ll need to take actions to prevent them from entering your home, and actions to get rid of any that have already gotten in. We speak extensively elsewhere about specific strategies for prevention and elimination – and you’ll want to read those, too. Here’s how to start right now:
They’re usually happy living outside, but will go anywhere to find food, including the inside of your home. When they do decide to do that, they’re good at getting in. It only takes a tiny hole or crack in an exterior wall to let these bugs inside.
So that’s your first course of action – finding holes, gaps, and crevices, and sealing your home up tight.
The next, and equally important chore is eliminating the roach’s food sources. If possible, you should store garbage far away from your home until pickup day. Bury your compost pile or use a bin with a lid to keep roaches out. And always clean up crumbs, counters and dishes before bed.
And the last part?
Active pest control usually involves using baits and pesticides to kill bugs, too. Residual sprays around the outside of your home can kill black roaches as they try to come inside.
We tell you elsewhere about specific chemicals used for treating a black cockroach infestation, but if it really is an infestation (as in lots and lots of roaches) you may want to instead consider calling a professional pest control service instead of taking them on alone.
Conclusion
It’s not only unnerving to discover that a big, black cockroach has somehow made your space its own, it’s dangerous. Even a small black roach (like a nymph) can carry harmful bacteria into your house and reproduce quickly if not controlled.
Now that you know how to identify these bugs and the steps to help eliminate them, it’s time to make it happen. To learn more, read about:
Frequently Asked Questions
Although black cockroaches have wings, neither males nor females can fly. Their wings–called tegmina–aren’t functional.
Oriental cockroaches are often called “black beetles” but they’re much different from beetles. Beetles are typically smaller and have a hard pair of protective forewings, known as elytra.
No. And they almost never bite (or even approach) humans. Usually, they’ll run away as soon as they see you. However, they do carry bacteria and viruses that can spread across any surfaces they touch.
Written by Andrew Martin. Reviewed by Rae Osborn, PhD.
Andrew Martin
Writer/Publisher
Andrew writes for, and along with his daughter, publishes Cockroach Facts. You can read more about him here.
Rae Osborn, PhD.
Science Editor
Dr. Rae Osborn holds Honors Bachelor of Science degrees in Zoology and Entomology, and a Master of Science in Entomology from the University of Natal in South Africa. She holds a PhD in Quantitative Biology from the University of Texas at Arlington, where her research was in Entomology. You can learn more about our contributors here.
Sources
- McCanless, Kim (2014) Oriental cockroach. Featured Creatures. Retrieved from http://entnemdept.ufl.edu/creatures/urban/roaches/oriental_cockroach.htm
