How to Spot a Rodent Infestation

January 14, 2019

The colder months will chase some pests away, but for others, it only gives them more motivation to move into your home or business. In fact, a survey by the National Pest Management Association showed that almost half of all rodent infestations take place during the fall or winter. Because mice and rats are good at hiding from sight, you may not even know that you have unwanted tenants until it’s too late, since seeing the rodent itself is often only a symptom of very serious infestations. To help you outfox these clever pests, PestLock has a few other signs of a rodent infestation that you should look for this winter. Read on to learn more, and call Portland’s Top Rated Local® pest control experts for the help you need!

What to Look For

Since seeing a mouse or rat is not a reliable way to gauge whether or not you have a rodent problem, you should look for other signs. There are several symptoms of a rodent infestation, from stale, musty odors to grease marks from their fur. We’ve concentrated on four of the most common signs of furry intruders. Whether you spot these symptoms or not, if you are concerned that you have pests in your home, call PestLock to schedule a free inspection and get a personalized rodent control solution!


One of the most obvious signs of rodents is droppings. They are typically small and dark, shaped similarly to grains of rice. Mouse droppings are often ¼-inch long or smaller, while rat droppings can be larger. If you do have rodents in your home, you will likely find droppings near food packages, under the sink, or in drawers or cupboards.

If you clean up these droppings yourself, it’s very important that you protect yourself! Many diseases can be transmitted through rodent droppings, including deadly strains like Hantavirus. Be sure to wear gloves and a mask, or call a professional team like PestLock to take care of it for you!

Unusual Sounds

Mice and rats can be very quiet creatures, but the noises they do make can often be easily distinguished from other sounds around the house. If you hear gnawing, scratching, or scampering, then you likely have a rodent infestation. These noises are often heard coming from the attic or ceiling or from within the walls as they travel through your building.

Chewing Marks

Another telltale sign of mice or rats is chew marks on food packaging or other materials, like cardboard or wood, throughout your home or business. Holes chewed through thin walls is another possibility. These pests can chew through everything from wood to wires to lead pipes in their quest for food, water, and easy access to these resources.

This aspect of a rodent infestation is another reason why you should seek help from rodent control professionals as soon as possible. Mice and rats can create real hazards within your building, from exposed wiring to structural damage. If you notice chew marks anywhere, call PestLock to schedule an inspection as soon as possible!

Nesting Materials

Rodents will use many types of materials to build their nests, including paper, fabric, insulation, and packing material. Aside from finding chew marks on these objects, you may find small scraps scattered throughout your home. If there is no other explanation for these messes – a naughty pet, for example – then it is likely debris from a mice or rat building a nest within your house or apartment.

What You Can Do

There are steps you can take to make your building less than desirable to these pests! One of your first steps should be to seal up entry points by filling holes with steel wool or patching up walls. You should also limit food and water sources for rodents and insects alike by cleaning up crumbs and addressing any plumbing leaks you spot. To protect your home or business from the outside in, remove potential nesting sites by clearing away leaf piles and redistributing deep mulch. For more advice, check out our winter pest control checklist!

Mice and rats can not only be nuisance, but they can also put your safety at risk through exposure to disease or hazards like chewed wires. If you notice any of these signs, contact the PestLock team right away! We are experienced pest control experts who are proud to serve Portland and Vancouver, and we can schedule your free inspection as soon as you contact us. Fill out our easy online form or call us today to take the first step toward a pest-free building!

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