Mouse, Rat or Packrat Droppings: How to Tell Them Apart.

The measures below are general guidance, and individual droppings vary. A technician confirms by looking at the location, the gnawing and other signs.

Do not rely on size alone. A cluster in an unusual place may belong to a different animal.

Mice leave droppings scattered widely as they travel and feed. Rats leave fewer, larger droppings in regular spots. Packrats often leave droppings near their nest or along regular paths.

• Scattered small pellets in a kitchen point to mice.
• Larger pellets in an attic point to rats.
• Droppings near a pile of sticks suggest a packrat.
• Droppings with food scraps or chewed packaging suggest a feeding spot.

Fresh droppings are dark and may look slightly moist. Old droppings turn gray and dry out. If you clean an area and new droppings appear the next day, the activity is current.

That test is useful but only if you clean safely. Wet cleanup with disinfectant is the method. Our guide on safe cleanup of rodent droppings lays out the steps.

Rodent droppings can carry germs, and dry droppings can crumble into dust. The CDC advises against sweeping or vacuuming them. The safer way is to ventilate, wear gloves, wet the droppings and wipe them up, then bag the waste.

If you have developed a fever, aches or trouble breathing after contact with rodent waste, tell your doctor. We are not medical professionals.

• Where you found droppings and how many.
• Their approximate size, compared with a coin or a grain of rice.
• Whether they look fresh or old.
• Whether there are other signs: gnawing, rub marks, odor.

A photo with a coin for scale is helpful. Leave droppings in place until the visit if you can.

The technician identifies the animal and traces the entry points. Trapping and sealing follow. See rodent inspection and estimates for how the first visit works. If the area needs cleaning afterward, attic and crawl space cleanup explains it.

Droppings do not tell you how many animals there are, how long they have been there or how they are getting in. A few droppings can mean one animal passing through, and a pile can mean a nest nearby.

They also cannot tell you whether the animals are still present. The best plan is to combine the evidence: droppings, gnawing, rub marks, noise and smell. Together they give a technician what is needed to name the animal and find the route.

• Look for gnawing next to the droppings.
• Look for rub marks on the path between a gap and the food source.
• Listen at night for activity.
• Notice any smell, which can mean a nest or a dead animal.

Do not assume the absence of droppings means no problem. Animals can be active in a wall or attic without leaving visible droppings. Noise, smell and gnawing count too.