Do rats eat roaches? [Dead or alive]

Do rats eat roaches? The sight of cockroaches and rodents in both residential and commercial buildings can be disturbing and irky. This cohabitation, however, is risky for the cockroaches since rats consider them food.

Rats prey on cockroaches like the American and German cockroaches, and over the years, entomologists have highlighted in publications that like humans, rodents and other carnivores are generally cockroaches’ predators.

Do rats eat cockroaches?

Generally, rats prefer food crumbs and other food sources, and would only invest their energy in going after cockroaches as an alternative. That said, roaches are simply an additional food source for rats.

Cockroaches will only only be a major food source for rats if there is a severe cockroach infestation, with several hundreds of roaches moving around the apartment.

Nevertheless, rats quite get along with roaches if they live on the same property. But that doesn’t stop a rat from eating one—roaches are just not a regular rat meal.

Both rats and cockroaches are nocturnal—they prefer food search at night, so they are likely to come in contact occasionally. However, since both have different objectives, a rat will almost pay no attention to cockroaches on its path unless it does not sense other food sources nearby. In some cases, if you see a rat eating a cockroach, it was most likely dead before the contact.

In one research, immobilized German cockroaches flushed out of cracks and crevices by pyrethrin aerosol were observed getting eaten by rats. This opportunistic predatory behavior by rats further explains that rats are capable of killing and eating moving cockroaches, even if it means going up the stairs.

Cockroaches and rats roaming in the house

If you have seen roaches and rats roaming in your house, you have an infestation, it could be a severe one that requires pest exterminators. At the same time, it is possible that the rats are feasting on the roaches—this is evident if you find roach heads, wings, and legs scattered around.

We explained earlier that rats feed on roaches. In fact, several labs and fieldwork reports have verified this claim, and rats even eat cockroaches captured in glue traps. So, you may sometimes find that parts (head, antennae, legs, etc.) of the cockroaches are missing in your sticky trap. Rats’ predation explains this event as they can carefully eat the remains without trapping themselves.

That said, you would also notice the presence of rodent hairs stuck on the glue. The stuck hairs on the sticky trap are usually from the rat’s chest area. This also means that rats not only eat live roaches but also eat dead ones.

Do you have a pet rat? So, can a pet rat eat roaches? Yes, pet rats eat cockroaches, whether large or small but only as an alternative if they can’t find other sources of food.

How rats catch live cockroaches

When rats pick interest in roaches as food, it means they can’t find food and have resorted to roaches to survive. As they come by roaches in the predatory event, they stay about half an inch away sniffing the cockroach with eyes partially closed.

In some cases, the rat will withdraw during the first few encounters if their chance is low or the roach is in the open. Once the opportunity seems right, they strike with one or both front paws. If the predation is successful, rats tend to pin captured cockroaches with their front paws and then feed on them from the head. Rats may also bite through the cervical region of the insect before going after the wings and the legs. According to popular opinion, rats can feed on the soft viscera of the cockroach’s abdomen or the entire parts, including the exoskeleton.

Roach importance to predators

Roached and their droppings contaminate food, causing intestinal diseases, such as dysentery, diarrhea, cholera, and typhoid fever. Other diseases include campylobacteriosis, cholera, gastroenteritis, leprosy, listeriosis, and salmonellosis.

These critters can be difficult to control, with two major reasons being their prolific reproductive habits and ability to develop resistance to insecticides.

Thanks to rodents like rats that feed on them—they help reduce the number, especially when there are no accessible food sources available. Cockroaches supply excellent sources of nutrition to rodents as they are a protein powerhouse—Healthline.

Also, rats enjoy energy and body insulation against cold from consuming fats from cockroaches. The daily physiological activity, building of tissues, and reproductive cycle of rats are catered for by roach proteins. Rat body functions are also made possible by minerals as well as certain digestive benefits from the chitin in the cockroach exoskeleton.

How to keep rats and cockroaches away

While rats may help reduce the cockroach population in your home, it’s still not the go-to solution. Moreover, this form of elimination is still one-sided since you’d be housing more rats in the near future.

Use this guide as your handy reference to address and prevent both rats and cockroaches from taking over your home.

1. Identify rat and roach hotspots

Rats and roaches are not only a nuisance but also carriers of diseases that can contaminate food. These critters can damage your property and worsen allergies or asthma. Thus, you want to identify the hotspots to help expel them.

Identifying rat hotspots

  • Sightings of live or dead rats.
  • Droppings. Rat droppings are shiny black and 1/2 – 3/4 of an inch long.
  • Gnaw marks from rat teeth typically near holes and cracks.
  • Footprints. You should find greasy, dirty-looking streaks along walls and baseboards.
  • Nesting materials in piles of scavenged materials such as torn fabric, food wrappers, paper, and pillow stuffings.
  • Urine smells like strong ammonia.

Identifying cockroach hotspots

  • Live or dead cockroach sightings.
  • Brown or black dots resembling coffee grounds.
  • Roach smear marks (usually dark, irregular-shaped stains).
  • Egg cases (ootheca) near the food sources.
  • Shed skins left behind after molting.

2. Clean affected areas

Cleaning your property is the first step to expelling rats and cockroaches. Start by reducing clutter and store items in sealed bags to discourage rodents and roaches.

Do not vacuum those areas with roach and rat poop—the dust may be contaminated with hantavirus which you may unknowingly inhale. The right thing to do is to ventilate and then apply disinfectant to the area. Do not use vinegar, it’s not a reliable disinfectant.

You should also inspect your rugs and curtains. If the rugs and carpets have rat and roach evidence, do not vacuum to avoid inhaling the dust. Instead, steam clean to get rid of insect larvae and eggs.

3. Eliminate food and water access

Two things keep these critters in your home: food and shelter. Since pests need crumbs and moisture sources (from a leaky drain or condensation), you want these cut off to starve them. Do the following:

  • Store food in sealed containers before sleep.
  • Don’t leave dirty dishes overnight.
  • Get rid of crumbs or food stains from your bed, stovetops, and counters.
  • Cover your pet’s food properly because rats and cockroaches eat your dog’s food.

Regarding keeping your property dry, find and repair any dripping pipes or faucets. Seal the drains using metal or rubber covers when not in use. You also want to vent the steam immediately after using the shower by leaving the bathroom windows open.

4. Block all pest entry points

Make repairs such as filling holes and cracks around floors, walls, and sinks to keep rodents and roaches outside. For this procedure, you’ll need safety gloves, steel wool or copper mesh, silicone caulk, and a caulking gun. You may also need duct tape or a staple gun and wire mesh screen for the finish.

Find gaps and cracks near baseboards where the floor meets the wall, sinks, bathtubs, cabinets, and plumbing lines. Use your caulking gun to seal narrow gaps with silicone caulk.

5. Use pest control solutions

Pesticides do not permanently solve the problem and rodents and cockroaches can develop resistance to these local store-bought products.

To get rid of the roaches, use insect powder like diatomaceous earth, boric acid, or silica gel. Gel bait, glue traps, and bait stations are also recommended for roaches. Use the pesticide according to the product instructions on the label and do not use more than the recommended amount.

For rats, get rodenticide bait stations or use bucket traps (if your bucket trap for rat won’t work, here are explanations). Non-humane traps include snap traps and glue traps. Instead, you should euthanize captured rats if you decide not to give them a second chance. Avoid the use of poison if you have pets or children around. Foggers, bombs, or loose rodent bait are not recommended as a rat control solution.


If your attempts to remove the rats and cockroaches yourself fail, contact your local pest exterminator for a professional and efficient solution. Pest problems can be irky and disturbing but not impossible to resolve, at least for a long time since pests will always return the moment you stop being proactive.


Leave a Reply

Your email address will not be published. Required fields are marked *