Do you need an exterminator?

Call on our services!

Get a quick quote

How do you know if mice have infiltrated your home?

January 6th, 2021

Mice can take up residence virtually anywhere in your house from the attic to the basement and everywhere in between. Mice build winter nests wherever they find access to a warm and protected space to store their food and survive the cold winter.

There are many different signs to look for if you are trying to figure out if you have mice in your house. Notice we weren’t tempted to say “a mouse in the house”. That’s because mice never live alone. Where you have one mouse, you have many, and considering that mice reproduce every three weeks, your unwanted pack of visitors could be growing more numerous as each day passes.

Fun fact: a group of mice is called a mischief of mice.

So what are the signs that you’ve got a mischief of mice in your house? In this blog post, the animal control experts at BW Nature serving Ottawa, Gatineau and the Outaouais walk you through the areas of your home from top to bottom to help you know what to look for if you’re worried that mice have infiltrated your home. Is there any other common winter pests?

Signs of mice in the attic

Mice in the attic will leave clues to their presence in the insulation and wooden joists, particularly close to the attic hatch or access point where heat loss makes it warmest. Here are some visual clues that you have mice in the attic:

  • Little 1-2 inch deep hallways or pathways dug and warn into the surface of insulation
  • 1 inch diameter holes where mice burrow and nest
  • Droppings and the smell of urine
  • Chewing marks in the wood
  • Stashes of food like nuts and seeds

The pitter patter noise of mice in the attic, or their faint chewing sounds are sometimes inaudible (hence the expression “quiet as a mouse”). At other times, especially in the dead of the night, their noises can seem louder than possible for such small pests.

Signs of mice in the walls

Mice are great climbers and once they find their way into walls, they can travel freely throughout your house. It is more common to hear mice in interior walls which are not insulated and it’s often easy to make out small scampering and chewing noises.

When mice nest or spend a lot of time in the walls, their urine can get quite strong since there is little air circulation. Mouse urine smells like ammonia and can radiate through holes such as outlets, switches, window and door frames, and along the bottom of the wall where it meets the floor if the mice are nesting in a stationary spot in the walls.

Signs of mice on the floor

Because mice are mostly nocturnal creatures, it’s quite rare to spot a live mouse running across your floor or along the bottom of a wall. There are some telltale signs to look for, however, if you think that you’ve got mice who are moving through the floor inside your home.

  • Tiny and closely spaced footprints in dust (you can even lay down some flour if you suspect that you’ve got mice and don’t have a dusty home!)
  • Greasy patches along the quarter round or bottom of the wall along the floor where the fur of the mice has rubbed up against the walls
  • Gnawing and bite marks in the quarter round, door and low window frames, and wooden or plastic furniture
  • Trails of crumbs from mice transporting food back to their nests
  • Dried yellow urine and dark droppings that look like black grains of rice in corners, cupboards, drawers, and under appliances

Signs of mice in the basement

The clues that mice leave in the basement are a combination of everything from the attic, walls, and floor since many basements have a mixture of finished and unfinished areas. Mice will be attracted to the buffet of dry foods commonly stored in basements and often chew through boxes and containers in the basement pantry.

Mice also find enticing materials for nest building and might leave the tell-tale signs of shredded pieces of insulation, clothes, linens, cardboard boxes, books and plush toys.

Basements are often the favourite nesting place for mice because of the numerous outside access points such as the holes from various pipes, cables and wires that pierce the foundation. Unfinished ceilings, exposed walls and open ductwork in basements make it easy for mice to get into floors, walls and then travel undetected to all areas of the house.

Signs that it’s time to call in the professionals

Some mice infestations can’t be dealt with without the help of professionals. Signs that it’s time to call in the experts include:

  • Unable to find the nest
  • Not knowing where the mice are gaining access to your house
  • Large amounts of mice droppings and urine which require decontamination
  • Rotting odors from dead mice
  • Infestations that are too large and established to use DIY traps

The pest and animal control specialists at BW Nature can help you locate, get rid of, and prevent future infiltration of mice in your house. We serve the Ottawa, Gatineau and entire Outauoais regions and offer solutions to help you with your specific pest control problems. Don’t hesitate to ask us your questions even if you’re unsure that you’ve really got mice in your house – we’re here to help!


Privacy policy

By agreeing to share certain navigation information with us, you are helping us to improve and offer you an optimal browsing experience. Thank you for your support! Privacy policy

Activate the categories you want to share, thanks for your help! Privacy policy

Consent date :
Consent ID :
  • Google Analytics
  • None for the moment
  • Google Ads Conversion
  • Google Analytics
  • Conversion Linker