Warning Signs of a Rodent Infestation

Brown rat looking to the side.

There they are again — those strange scratching and skittering sounds that might be coming from the wall. Surely, it’s not what you dread most — a rodent infestation (ugh!). Unfortunately, mice, rats, and other rodents do move into buildings, seeking warmth, food, and shelter. While winter’s cold is a primary force driving these critters indoors, storms, rain, and drought can do so, too. Before you panic over the sounds, look for other signs of a rodent infestation. Rest assured, if you need rodent control, Mosquito Joe® will handle it for you.


If you discover dark gray, brown, or black pellets that look like grains of wild rice scattered in a drawer, on the breadboard, or in your cupboards, those are likely rodent droppings. (Cockroach droppings look similar.) Droppings left near a food source are often the first signs of a rodent infestation people encounter in their homes.

Gnaw Marks

Mice and rats chew through cereal and cracker boxes in search of food. If you find bite marks on cardboard boxes or plastic bags, it’s a good indication that you may have rodents in the house. The larger the tooth marks, the bigger the beast that left them.

Chewed Wires or Materials

Rodents chew on everything. Once they are in your home, they continue chewing — on the baseboards, drywall, doors, electrical cords, ledges, and anything that gets them closer to food.

Urine Stains

Urine stains are another common sign of a rodent infestation. The urine may be soaked up by cardboard, paper towels, and other absorbent materials. In that case, you’ll just see the stain left behind. You may also notice a dirty smudge or smear along your baseboards. These are urine stains tracked by tiny feet as they move about your home.

Nesting Materials

If you discover shredded paper, paper towels, fabric, or other small bits of soft material gathered or in a pile, you have found a rodent’s nesting materials. While they sometimes nest for comfort, the most common reason they nest is because they are planning a family.

Scratching or Scurrying Sounds

Back to the unexplained sounds: Gnawing can sound like scratching, and rodents make scurrying, scuttling sounds as they race across the floor, along the baseboards, or within walls. Chances are you are hearing rodents if you’re also hearing high-pitched squeaking.

Pets Acting Strangely

Sometimes, the first indication of mice or rats in the house is the reaction of your cat or dog. If you notice your pets acting strangely, scratching at a wall, or gravitating toward one specific room, look for other signs of rodent activity.

Strange Smells

Strange smells like stale ammonia are another sign of a rat infestation, as they are indicative of rodent urine and droppings. A potent smell reminiscent of rotting cabbage is another odor associated with mice and rats. It is the smell of a dead, decaying rodent. (Blech!)

Live or Dead Rodents

If you spot a rodent in your home, living or dead, there’s a good chance you have more. They are social creatures and reproduce quickly.

Why Is Identifying Signs of a Rodent Infestation Important?

While some people would shriek in fright at the very notion of a rodent in the house, others take a live-and-let-live approach. That can be a fine attitude with wildlife outdoors, but you really must avoid a rodent infestation in your home. Protecting your family’s health and preventing property damage are the best reasons to watch for signs of a rodent infestation.

Rodents are known to carry many diseases, including several that can spread to people directly and indirectly. Diseases like Hantavirus, Tularemia, and Monkeypox are spread directly through contact with an infected animal, such as eating contaminated food, touching their urine or feces, or getting bitten or scratched. Other diseases like Plague, Lyme disease, and Colorado tick fever are contracted indirectly by beIfflea, tick, or mosquito that previously bit an infected rodent.

In addition to carrying disease, rodents cause tremendous property damage. Americans splash out hundreds of millions of dollars repairing property damaged by rodent infestations every year. Most insurance companies do not cover the damage rodents do to HVAC equipment, electrical wiring, roofing, flooring, walls, baseboards, or furniture.

How to Prevent Rodent Infestation

The very best rodent control is rodent prevention. The goal is twofold:

  • Stop attracting rodents to your home and property, and
  • Deny them entry to your home.

What attracts rodents, pets, or any wildlife to your property are the things they need to survive. Food, water, warmth, shelter, and propagation support are the resources they are hunting. If your property provides what they need, they’ll move in, which brings them closer to your home. If rodents take up residence in your garden, they’ll come into your home the next time they cannot meet their needs outdoors. There are several steps to effectively prevent a rodent infestation:

  • Seal up entry points to your home.
  • Install screens on chimneys and vents.
  • Keep all food and food waste cleaned up and sealed away.
  • Store firewood properly.
  • Trim shrubs and trees.
  • Keep the yard tidy and clean.
  • Eliminate leaky fixtures.
  • Use natural deterrents.
  • Hire professional residential pest control.

Why Hiring a Professional Rodent Control Is Better Than DIY

Preventing a rodent infestation is where homeowners should focus their efforts. If you catch a single mouse investigating the premises, DIY efforts may be all that’s needed. But once the mouse’s friends and relatives have moved in, the situation quickly spirals out of control. Often, it’s difficult to find or reach the heart of the colony, leaving your best efforts just nibbling at the edges of the problem. A female mouse gives birth to a litter of five to six babies between five and ten times a year. This rapid birth rate plus the rodents’ extraordinary survival skills make professional rodent control a better bet than DIY strategies.

Worried About Rodents In Your Home or Business? Call Mosquito Joe!

When you see signs of a rodent infestation on your property, call the pest control experts at Mosquito Joe. Our comprehensive pest control services include keeping rodents out of your home or business. We evaluate your property to locate nesting sites and runways the rodents repeatedly use to get to their food sources. We treat these locations and form a barrier around your structures to keep the critters outside.

Trust Mosquito Joe to protect your family and property. All our work is backed by the Neighborly Done Right Promise™ and the Mosquito Joe Guarantee because the job’s not done until it’s done right.

Request a free quote today, and look forward to a rodent-free tomorrow — with Mosquito Joe!