Ask a homeowner what they heard in the ceiling and they will say a mouse. Ask what they found in the garage and they will say a rat. Often neither guess is checked, and the difference determines what kind of visit comes next.
Droppings, compared.
| Animal. | Typical droppings. | Where they turn up. |
|---|---|---|
| House mouse. | Small and dark, roughly a rice grain, with tapered tips. | Kitchens, drawers, pantry shelves, wall voids. |
| Roof rat. | Larger, spindle-shaped, often with pointed ends. | Attics, beams, along wires, on top of garage shelves. |
| Norway rat. | Thick, blunt-ended capsules. | Near the ground, along foundations, in sheds and basements. |
New pellets look dark and slightly moist, while aged ones fade to gray and crumble. Old pellets mixed with a few new ones point to a route in long use.
Habits and travel routes.
- Mice prefer to stay close to their nest and travel only a few yards.
- Roof rats climb and favor high places such as attics, roof edges and trees.
- Norway rats burrow and tend to stay near the ground, using tunnels beside slabs, fences and sheds.
- All three follow the same walls and pipes repeatedly, which leaves smudges and rub marks.
Knowing which you have tells a technician where to concentrate. A roof rat problem starts with the roofline and trees. A Norway rat problem starts at the foundation and in the yard. A mouse problem starts inside, in the kitchen, the pantry and the wall voids.
Gnaw marks and what they say.
Mouse teeth leave small, fine marks. Rat marks are larger and rougher. Look at the edges of a chewed box, pipe or door frame and compare the size of the grooves. If you see marks on hard materials such as wood trim, plastic pipe or soft metal, rats are more likely.
Fresh gnawing is lighter in color. It darkens with age and dirt.
Nests, and where to look.
- Mouse nests: fluffy balls of torn paper, cloth or insulation, usually in drawers, cartons or behind appliances.
- Roof rat nests: loose piles of leaves, insulation and debris in attics and trees.
- Norway rat nests: shredded material in burrows or at the base of a wall.
If you find a nest, do not touch it with bare hands. Wet it with disinfectant and wear gloves, as the CDC advises. See our cleanup guide for the steps.
Not ready to book anything? Chat with us anyway, because a question commits you to nothing.
(888) 686-4821Why the species changes the plan.
| Question. | Mice. | Rats. |
|---|---|---|
| Entry gap size. | About the width of a pencil. | A little wider, but often enlarged by gnawing. |
| Trap type. | Small snap traps or enclosed stations. | Larger traps, often in enclosed stations. |
| First place we look. | Kitchen, pantry, wall bases. | Roofline, trees, foundation, yard. |
| Sealing focus. | Small pipe and cable gaps. | Vents, soffits, roof edges, slab gaps. |
Because the plans differ, a wrong guess wastes time. The mouse page and the rat page go into the details.
A short field test.
If you are curious, try this for a few nights. Lightly dust a strip of flour along a wall where you suspect activity, or place a small piece of white paper. In the morning, look for tracks and tail drags. Do not use poison.
A narrow trail of tiny prints suggests mice. Larger prints with a tail mark suggest rats. Record what you see and share it when you call.
Noise and timing.
- Light patter and quick scampering suggest mice.
- Heavy thumps and dragging suggest rats.
- Activity just after dark is typical for both.
- Daylight noise in the roof is more often a squirrel.
We cover this in more detail in our night noises article.
What a technician adds.
A technician reads droppings, gnaw marks, grease smears and burrows together, and checks entry points that you may not be able to see. The result is a named animal, a map of its route and a written plan. See the inspection page for what the visit covers.
Calling with what you have found.
Describe the droppings, mention where you found them and tell us what you heard. Photographs help. You do not need to be certain, because naming the animal is part of the visit.
Before you call: handling droppings while keeping dust down.
The agencies largely agree on how to clean up safely, so their shared method is boiled down here.
- Whatever you reach for first, put it back if it is dry: brooms, vacuums, compressed air and rags all count.
- A shut-in space needs time to clear, so open it, leave and return when about thirty minutes have passed.
- Gloves protect the hands, and hands touch faces, so keep the gloves on until the last bag is tied.
- Spray generously, step back, give it a few minutes and then lift the mess with disposable towels.
- Bagging keeps stray particles from drifting through the house on the way out.
- Feeling sick after handling rodent waste is a matter for a physician, so tell them exactly what you touched.
Government pages we relied on.
Each link opens the agency's own site with no sales pitch attached.
- CDC website: clean-up instructions: Air it out, soak it and bag it, in the order the CDC sets down.
- Prevention page on hantavirus, CDC: Keeping well around rodents through sealing, then trapping, then cleaning.