How to Identify a Mouse Problem

The sooner you can identify a mouse problem, the sooner you can get rid of them in your home.

The Types of Mice That Can Be Found In Canada

While the House Mouse is the most common species of mice to be found in your home, Canada is home to many other species of mice. Each species of mouse has their own unique characteristics despite all sharing the same interest in searching for food and water. With different mice living in different parts of the country, it is important to learn the differences between them to better identify what type of mouse you may be experiencing in your home.

House Mice

By far the most likely type of mouse to be found in your home, House Mice were brought to North America by settlers from Europe over 200 years ago and were given the name “house mice'' with consideration to having always lived nearby to humans since the beginning of time. House Mice are the smallest types of rodent and have grayish black fur with large ears. An adult house mouse can range between 6 to 7 inches in length and weigh around 28 grams (1 oz).

At full health, a female mouse can birth up to 10 litters of 6 baby mice every year. Mice pregnancy can take up to 6 to 10 weeks as their life span is a maximum of 1 year. For these rodents to thrive, mice prefer to nest in secluded areas that are less frequented by humans and animals but still only 10 to 30 feet away from a source of food and water.

Given how quickly House Mice produce, it is important to take action in your home if you identify these rodents.

mouse next to plant

Deer Mice

Named after the same colour of fur that they share with deer, Deer Mice can commonly be found in fields and are also referred to as Field Mice. This mouse species can grow as long as 20cm (8 inches) in total length and weigh around 1 to 3 grams at the most. Known to be found in more of rural Northern Canada than in more populated areas of the country, Deer Mice still go looking for shelter in homes that are conveniently nearby to fields and parks despite this being a rare occurrence. Deer Mice found in homes are more likely to occur in the winter season and cause serious danger to your home in the form of physical damage to your home and diseases.

deer mouse

White-footed Mice

Also known as Woodmice, White-Footed Mice are named after the white fur seen on their paws although other species of mice share similar colourage in their paws as well. White-Footed Mice are native to Ontario, Quebec and the Maritimes, as well as part of the southwest of the United States.

This species of mice favour dry forests and bushland while also having an interest in finding their way into nearby homes during the winter. White-Footed Mice are considered omnivores as they consume seeds and insects that can be found in areas that these mice commonly live. Although these mice have no problem finding food outdoors, they have no issues consuming food in your home as well in their pursuit for shelter during the colder months.

white footed mouse

Western Harvest Mice

Named for mostly being seen when crops are ready to be harvested, Harvest Mice can be found in the southern parts of Alberta and British Columbia in areas where they can satisfy their mainly vegetarian diet with seeds and berries from crops of all kinds.

Harvest Mice grow to be as 12cm (5 inches) long with tails that enable them to wrap around field stalks and climb them with ease. Although these species of mice have no problem finding sources of food outdoors, Harvest Mice still have the ability to find their way into houses and barnyards in open farmland. These mice are especially inclined to enter your home if there is a food source nearby that makes it extremely easy for them to get to.

western mouse

Woodland Jumping Mice

Woodland Jumping Mice can be found leaping through open fields, woods and meadows that are moist due to nearby water across Central Canada and the Maritimes. With tails more than double the length of their body, these mice get their name from being able to jump as high as 9 feet in the air with ease.

These mice consume a variety of insects, seeds, fruit and even small fish which are all items that can be found in the woodlands that they live in. Their nests can be found almost anywhere including nearby homes, which can be an ideal destination for the Woodland Jumping Mouse during hibernation in the winter.

woodland mouse

Common Habits and Characteristics of Mice

How Mice Enter Your Home

Similar to rats, mice only need a mere crack in the corner of your home for them to begin to enter your living space. When they’ve identified a way to get into your home from its exterior, mice can use a hole in your drywall as small as the size of a Canadian dime as an easy entrypoint. Cracks in your wall that are not yet large enough for House Mice to enter are used as starting points for these rodents that can easily chew drywall to develop a hole to the size of their preference.

Some common places outside that mice are known to enter your home from are:

  • Unrepaired holes in the exterior of your home
  • Cracks and crevices in your home’s exterior
  • Cracks in doors and windows
  • Open doors and windows
  • Through the garage
  • Weather-strip gaps in doorways
  • Unsealed pipes, drains and vents

Favourite Food Types

Although mice and other rodents are receptive to consuming just about anything, mice are most receptive to cereal grains. Mice are notorious for bringing grains in crumb form back to their nest for storage and will commonly leave a trail of crumbs back to their nest when scavenging. Mice can eat up to 2 grams (1/10 of an ounce) of food each day. In addition to cereal grains, here are some other types of food that House Mice are interested in:

  • Sweet Fruits and Berries
  • Pet Food
  • Nuts
  • Nearly Any Kind of Meat
  • Grains and Seeds
  • Plants
  • Dinner Leftovers


Mice are not known to burrow underground, but rather, at ground level in houses, residential and commercial buildings. Mice that do live in the wild can be found developing nests in dense vegetation, grassy fields, forested areas and farmland. Mice prefer burrowing and nesting near heat sources to keep warm while using fibrous material such as shredded paper and leaves as a means to create their nest.

Signs of Mice in Your Home

Mice are so small and nimble that they may be difficult to see in your home if only a few. These nocturnal rodents are most active at night which is why it is more likely to see droppings and damage that they’ve left behind as opposed to seeing them for yourself.

woman looking in cupboard

Chew Marks & Holes

Mice will chew their way through anything in pursuit of food and water. When finding a way into your home, chewing and gnawing at just about anything helps them determine the best way into different living spaces and where to create a hole for entry.

Damaged Food Packaging

House Mice’s sense of smell is advanced enough to identify food in even the slightest of open packages. What may start as a broken seal of a food container can turn into an entirely opened package in a short amount of time.

Changes in Pet Behaviour

Dogs and cats that have become more attentive to walls and other places in your home that they usually do not pay attention to are likely detecting mice that human ears may have not yet noticed. Paying close attention to pet behaviour can lead to the discovery of a mouse problem in your home.

Chewed Furniture and Boxes

In addition to scavenging for food, mice are small enough to burrow in many places. Boxes and inside of couches are all places that House Mice have been known to nest as they also damage furniture in the process.

Sounds & Activity

Squeaking and scratching noises, especially at night, are typical sounds that these nocturnal creatures can make when moving around your home. House Mice use the inside of the walls in your home to navigate to different parts of your home when you least expect them.

The Significance of Droppings and Urine Odour

Mice droppings are much smaller than rat droppings and can be as long as ¼ inches. These rice-shaped droppings can almost always be found scattered and in multiple amounts as mice drop about 50 to 75 pellets per day. Droppings and urine can always be found at the same time and can cause harmful pathogens that not only cause surface damage to floors and other areas of your home, but also affect the health conditions of your home.

Although House Mice do not carry pathogens the same way as rats, the fecal matter and urine of these rodents are still poisonous and can lead to further damage. Read our article to learn more about the dangers of rodent droppings and how to handle them in your home.

mouse droppings

Signs Of An Infestation

Should any signs of mice be heightened over time, the more likely it is that there is a mouse infestation in your home. More droppings, further agitation from your pets and more sounds and activity coming from the inside of your walls are sure signs that an infestation is occurring in your home.

As nocturnal rodents, mice are typically not seen in the day time although the abundance of rodents in your home during an infestation can lead to the potential of House Mice being seen due to the sheer amount of them in your home. It is important to begin taking steps towards controlling infestations immediately as soon as you discover any signs of mice in your living area.

How Mice Can Damage Your Home

Despite being smaller than most rodents commonly found in and around Canadian properties, mice can cause a large amount of damage to your home very quickly when left unattended for too long. These rodents are known to chew through anything in your home in order to find weak points in your home’s structure that will give them access deeper into your living space for food and water. Drywall, baseboards, food packaging and wired cables can easily be damaged by mice in your home and become unrepairable very quickly.