What Do Mouse Droppings Look Like & What To Do If You Find Them

Seeing a mouse in the house is upsetting, but finding out that a rodent infestation has been lurking in your home for a long time is even worse. Knowing how to identify the signs of a pest problem will help you prevent infestations and keep your home pest-free.

Finding mouse droppings is one of the most obvious ways to discover you have a problem in your home. We discuss what their poop looks like, the dangers of mouse poop in your home, and what to do once you discover the issue.

Is There a Rodent in Your Home?

Before you see an actual mouse, you may notice signs of them — but if you don’t know what to look for, you may miss the signs! From “mice rice,” to “droppings,” knowing how to identify mouse poop can give you a head start when it comes to preventing these infestations from happening in your house.

Recognizing and being able to identify rodent droppings will give you the chance to clean up their poop properly. This will help prevent disease in your home and assist in getting rid of them before the problem gets out of hand. The dangers include many diseases that can be spread through their feces — from salmonella to Hantavirus — so cleaning up after an infestation is especially important.

What Does Mouse Poop Look Like?

Mouse droppings look similar to a grain of rice, ranging in size from 3/16 to ¼ inch long. The pieces typically have pointed ends and a color varying from blackish brown to gray depending on how old it is and the diet of the mouse.

Fresh droppings are black, they turn brown over the next week, and change to grey over time. If a rodent has consumed pesticide from a bait station, the droppings may be the same color as the bait. Older droppings will crumble upon contact, while fresh ones will be soft and malleable (never touch with your bare hands).

Mice can leave behind 50-75 pellets per day. The number and size of droppings you see can help you determine the severity and type of pest problem you are facing. These critters will poop while they are moving, so droppings will be seen along the paths they travel and in the places where they are finding food. They may poop near their nest, but they will not go to the bathroom in their actual nest — believe it or not, they like to keep their homes clean!

Does Mouse Poop Smell?

While the droppings may not have any noticeable smell, mouse urine has a distinct ammonia smell. They have very poor eyesight, but a highly developed sense of smell. They can gather information from the scents left behind by rodent waste, such as where to find food and what areas to avoid. While you may not be able to find their droppings by smell, you may notice an ammonia smell from the urine they leave behind, and you can be certain it is the work of more than one of them.

What Do Rat Droppings Look Like?

Although identifying droppings is a good way to figure out what kind of pest problem you have, it can be confusing. Rodent infestations can be the result of house mice, deer mice, roof rats, Norway rats, and even squirrels or raccoons.

Rat poop is generally the same shape as mouse feces with pointed ends, has a similar black/brown color, but they are larger. They are usually about a ½ inch in size, so that’s the best way to differentiate them. Squirrel droppings are similar in shape, but a little larger and thicker. Raccoon poop is more similar in appearance to a small dog’s poop.

How to Get Rid of The Droppings

After you’ve identified rodent droppings, you have to get rid of them. They are not just unsightly, they can also spread diseases. You must follow safety precautions when cleaning up mouse droppings. Take this advice from the CDC:

• Air out the space for 30 minutes before cleaning if possible.
• Wear rubber, latex, or vinyl gloves and a mask or respirator.
• Use a disinfectant spray (DIY by mixing 1 part bleach to 10 parts water) and soak area for 5 minutes.
• Clean area with disposable rags or paper towels.
• Put waste in a sealed plastic bag in a covered trash can.

It is especially important to avoid sweeping or vacuuming areas where mice have been until after these steps have been completed. Sweeping or vacuuming can cause germs to circulate in the air; if you inhale any pathogens from rodents, you could become seriously ill.

Cleaning up after these pests is not an activity you want to repeat, so take time to inspect the area for potential entry points they may use to come inside. They can enter through an opening that is smaller than a dime, and can easily chew through foam insulation, wood, and plastic. If you notice any cracks around doors, kitchen cabinets, or window frames, or open space where pipes, cables, and utility lines pass through the wall, block the openings with steel wool. Use silicone caulk to fill in cracks and gaps. 

Make the area less attractive to household pests by cleaning up any available food sources such as dirty dishes, uncovered trash cans, or unattended pet food. Clear clutter so mice have fewer places to hide, and consider using a rodent repellent to prevent this from happening again.