5 Tell-Tale Signs of a Rodent Infestation

D.P. Taylor
Written by D.P. Taylor
Updated July 12, 2021
Family sitting on sofa watching television
10'000 Hours/DigitalVision via Getty Images

If you spot droppings, nests, and holes in your walls you may have mice or rats in your house

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If you’ve ever been sitting on your couch watching TV only to spot a rodent scurrying through your living room, you know it’s not a great feeling. And though it’s totally possible this was just a one-off, it’s natural to wonder if you’re just dealing with one rodent, or an infestation.

Preventing mice and other rodents from entering your home and setting up shop is vital to your health and safety. Here are some signs that you have an infestation and what you can do about it.

1. Droppings

What it is: Droppings are the feces left behind by mice, rats, and other rodents in your home. You'll tend to find them in areas where rodents feed or nest, so if you find them, you're close to where the problem is.

What it looks like: Rodent droppings appear as small brown pellets, about the size of a grain of rice. However, they will vary in size depending on what type of rodent you have. If it's a mouse, the droppings will be only a quarter inch at most, but rat droppings can be up to three-quarters of an inch.

What it means: Droppings are a sign that the rodents have settled in and are regularly eating and/or nesting in that area, so you'll need to drive them away to keep them from coming back.

What to do: Inspect the area around the droppings for signs that rodents may have been coming from other places in the home, or for holes that mice may be using as entry and exit points.

2. Nesting Material

What it is: Rodents use just about any piece of material they can get their mouths on to build their nests, which usually consist of fabric, paper, and even plants. These materials can provide good clues of where in your house the rodents have been.

What it looks like: Rodents will build their nests in a rough, ball-like shape. A clump made up of random materials like those described above that is tucked away behind a refrigerator or in a basement is likely a rodent nest.

What it means: Rodents build nests to conserve heat, as well as to raise a litter. So, a nest is a sign that the rodent has settled in and is living in that area, and  is not just passing through.

What to do: Search the surrounding area for any other rodent nests and note the location so you can relay that to pest control. If you want to dispose of it yourself, use gloves to avoid coming into contact with any diseases or any rodents still in the nest. However, just getting rid of one nest won’t be enough if there are other nests in the area, so you may need to call an extermination expert near you.

3. Holes in the Walls and Flooring

What it is: Rodents need entry points throughout your home and will chew holes in the walls and floors.

What it looks like: You’ll usually find a rodent hole near where the floor meets the bottom of the wall. They are generally only about two to four inches across, making them tough to spot, particularly if there are objects like desks or appliances in front of them.

What it means: Holes mean that rodents haven't just snuck in through a temporary opening—they have free rein to enter and exit your home whenever they please.

What to do: Search for holes the rodents are using and plug them up in order to keep rodents out of your home in the future. If you catch one out in the open, they will often flee directly to the nearest hole, which is a good way to find these entrances. However, they're tough to spot, so you may need an expert to check your home.

4. Strange Smells

What it is: Obviously, the smell of feces is a dead giveaway, but that's not the only odor rodents leave. They will also leave other strange smells, so you should investigate for rats in your house when you notice an unusual odor coupled with other signs.

What it looks like: You may smell feces, but you might also notice a stale smell coming from hard-to-access areas if there is an infestation.

What it means: As an infestation grows, so does the amount of feces and other rodent activity, and therefore the smell will go stronger as well. Intense odors are a sign of an infestation that is out of control and may need a professional.

What to do: Investigate the area where you smell the odor most strongly. You may be able to dispose of any nests and clean up the area, as well as lay some traps, but at this point, it’s probably time to hire an exterminator.

Mouse chewing on electrical wire
tenra/iStock/Getty Images Plus via Getty Images

5. Sightings

What it is: The most obvious sign of an infestation is if you see rodents scurrying about in your home. When you see one, often there are more.

What it looks like: Rodents don't like being seen and will usually flee to their preferred hiding spots or exits if a human approaches. You might catch a glimpse of a rat scurrying away out of the corner of your eye. Or, you might catch one out in the open after turning on a light in the kitchen.

What it means: If you are seeing rodents during daylight hours, that is a sign of an infestation. If it were just one or two rodents, you might only notice them occasionally at night. But if they are out during daylight, it's a sign of a larger population.

What to do: When you spot one, take note of where it goes when it flees. This will likely tell you where the holes in your home are, as well as any nesting locations.

Pest Control Can Solve Your Rodent Infestation Problem

Rodent infestations are not something you should take lightly. Even if you aren't particularly bothered by the sight of mice or even rats in your house, they carry disease and place you and your family at risk.

If you think the infestation is small enough, you can try setting out traps or plugging up holes to see if that takes care of the problem. But if you suspect you have a larger issue on your hands, contact an exterminator near you to conduct an inspection and recommend some next steps. You may be surprised at how little a mouse and rat exterminator costs. Plus, ridding your home of these furry foes is worth the cost.

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