What are the signs that there are still mice in the house?

You have a rat problem in your home, but you think you or the pest control professional you hired has gotten rid of all the rats. But how can you be sure? Are those droppings you found under your cupboards old or new? Do the rodents you just found mean there are more rats in your home? Or is this an old infestation? Here are some signs and tips to help you tell if you have a current or previous rodent infestation in your home:

Table of Contents

Rodent Droppings

Animal Gnawing

Foul Odors

Rat Tracks and Runways

Rat Nests

Signs of Rodents in the Yard

Rodent Population

Rodent Droppings

New droppings are dark and moist. As droppings age, they dry out, become old and gray, and crumble easily if touched. Droppings are most likely to be found near food packaging, in drawers or cupboards, under sinks, in hidden areas, and along rodent runways. Droppings are most abundant where rodents nest or feed, so check the area around newly found droppings to determine if there is still an active or new rodent infestation.

Animal Gnawing

Newly found gnaw marks are lighter in color than droppings and get darker over time. These marks often appear on food packaging or the structure of your home. One way to determine age is to compare gnaw marks you just found to gnaw marks on similar material that you know are older. If the newly found marks are lighter in color, it may indicate an ongoing infestation.

These marks can also indicate whether you have rats or mice; larger gnaw marks are caused by the larger teeth of rats. So if you have rats but now see larger gnaw marks, it may now be rats. The reverse is also true.

Foul Odors

Cats and dogs (even pet rats) may become active and excited in areas where there are rodents.

This is a result of rodent odors and is most likely to occur when rodents have recently entered the building. If you see your pet scratching in an area it previously had no interest in, use a flashlight to check the area for rats or mice. (If you just found a lost toy or pet treat - you're in luck this time!) If the infestation is widespread, you may also detect a persistent stale odor coming from a hidden area, which indicates an active infestation.

Rat Tracks and Runways

If there is rodent activity in or around your home, their runways and tracks may be very obvious and become increasingly faint over time. Tracks or tracks are easiest to spot by pointing a flashlight or blacklight at an angle toward the suspected area. You may see stains, footprints, urine stains, or feces. If you suspect an area is frequented by rodents, try spreading a very thin layer of flour or baby powder there. If rodents are active, you may see their tracks in the powder.

Rat Nests

Rodents use materials such as shredded paper, fabric, or dried plants to build nests. If you find these areas and any other signs that rodents are currently present (fresh droppings, gnawing, odors, or marks), it is likely that your home is still infested with rodents.

Signs of Rodents in the Yard

Garbage piles, organic waste, etc., can attract rodents to feed and build nests. If these garbage piles are near homes or buildings, check for signs of rodents. If there are no signs of rodents, they are likely not in your home. However, if you do have such garbage piles in your property, removing them can help prevent future rodent problems.

Rodent Population

Certain signs can also indicate rodent populations. If you see rodents at night but never during the day, then the rodent population is probably not too large and can be controlled with humane mouse traps and bait. If you see any rodents with large amounts of fresh droppings or new bite marks during the day, the rodent population is probably quite large and may require professional services.