If you’ve recently noticed the telltale signs of mice in your home—such as scratching noises in the walls, droppings in overlooked corners, or gnawed food packaging—you’re probably wondering, “Why do mice come into homes? And, “How do mice get into houses?” These tiny rodents are masters at finding their way into your home and making themselves comfortable—often long before you realize they’ve arrived. 

The problem usually isn’t just the one or two you spot; it’s important to understand how many mice live in a nest and just how quickly a small issue can escalate into a significant infestation. If you are wondering why you suddenly have uninvited house guests, read on. Our wildlife control experts in Niagara will answer all your pressing questions. 

How Do Mice Get into Houses?

Mice are astonishingly resourceful creatures. They can squeeze through a hole as small as a dime, climb vertical surfaces like siding or brick, and leap surprising distances. Homes of all ages—whether newly built or decades old—offer ample opportunities for mice to find their way inside. Some of the most common areas mice use for entry include gaps in walls, utility pipe openings, foundation cracks, and weep vents. Even the smallest imperfection, such as an opening around your dryer vent or a poorly sealed window frame, is fair game for these determined invaders.

One of the reasons mice are so adept at finding their way into houses is their instinct to seek warmth, food, and shelter. Seasonal changes, especially harsh winters, can drive them inside in search of refuge. Once mice detect heat, they follow their noses—literally—to explore ways to enter your home. With their climbing abilities, they’re not restricted to ground-level entry points, either. Openings near your roofline, such as attic vents or gaps in soffits, present additional opportunities for entry.

Beyond their physical abilities, mice leave behind scent trails using urine and pheromones, creating a “roadmap” for other mice to follow. Even if the original intruders find their way back out, these trails can guide new mice into your home. This is why it’s so critical to address not just the mice you see but also the pathways and signs they leave behind.

Why Do Mice Come Into Homes?

Mice come into homes for three primary reasons—food, shelter, and safety. Your home often provides an ideal combination of all three, making it an irresistible destination for these furry intruders.

First, food is easily accessible in most houses. Mice have an acute sense of smell and are persistent when it comes to finding something to eat. Unsealed food containers, crumbs under appliances, pet food bowls, and even scraps inside your garbage can are all attractive options. Mice only require about three grams of food a day to survive, and their diet is incredibly versatile—they’ll nibble on everything from grains and pasta to fruits and even non-food items like soap when food is scarce.

Second, your home offers ample hiding spots and nesting areas. From the warmth and insulation of your attic to the dark, undisturbed corners of your basement, mice thrive in places where they can remain out of sight. Wall voids, ceiling cavities, and cluttered storage areas are prime locations for them to build nests. These nests are constructed from materials like shredded paper, fabric, and insulation—anything that’s easy to chew through and transport.

Lastly, homes provide protection from predators and harsh weather conditions. Outdoors, mice are vulnerable to hawks, cats, snakes, and other threats. Indoors, they feel much safer, especially in areas that remain undisturbed. For instance, an attic or behind drywall offers cover and security where mice can move freely without being noticed.

Their reproductive habits also make them difficult to manage once they invade. Female mice can produce litters of 5–10 pups every three weeks, which is why it’s crucial to address any potential infestation as soon as you notice signs.

How Many Mice Live in a Nest?

If you spot a single mouse in your home, it’s rarely just one. Mice are highly social animals that live in groups, typically within a nest. A single nest is often home to multiple adults and their offspring. The exact number of mice that live in a nest can vary, but it’s not uncommon to find 10–15 mice in a single colony. This means that if one nest goes unnoticed, you could be dealing with dozens of mice before long.

Nests are strategically located in places that are difficult for humans to access but convenient for mice to thrive. These include inside walls, under floorboards, behind appliances, or in piles of stored materials like boxes or firewood. They choose locations that are close to food sources yet hidden from predators and human activity. Because mice are nocturnal, their activity is concentrated during nighttime hours, adding to the challenge of detecting their presence early on.

Large infestations can result in multiple nests throughout different parts of the home, connected by the scent trails they leave. This is why addressing nests proactively is critical; eliminating one without blocking access points or cleaning up scent trails will only encourage new mice to move in and repopulate the space. Remember, a mouse’s small size and high reproductive rate mean an infestation can escalate very quickly.

Signs You Have Mice and How to Handle Them

It’s not always immediately obvious that mice are living in your home. When mice first infiltrate homes, they often go unnoticed due to their small size and cautious nature. However, there are several signs to watch for:

• Droppings: The presence of small, dark, rice-shaped droppings is one of the earliest indicators of a mouse intrusion.
• Noises: Scratching and scurrying sounds in walls or ceilings, especially at night, are a strong signal.
• Gnaw Marks: Mice chew on everything, from wood and wiring to food packaging and cardboard.
• Tracks: Footprints or tail marks in dusty areas can reveal their movements.
• Odors: A distinct ammonia-like smell from mouse urine is a common giveaway.

If you notice any of these signs, it’s time to act quickly. Mice infestations can lead to more than just inconvenient noises or nibbled food. Their droppings can carry diseases like salmonella, and their constant chewing presents a risk of fire if they damage electrical wiring.

At Skedaddle, we specialize in humane and effective solutions for removing mice and securing your home to prevent future invasions. Our process starts with a thorough property assessment—identifying every access point, no matter how small. We then carefully seal those entryways using durable materials and install exclusion systems to ensure mice can leave but not return. By addressing nests, entry points, and contamination in one comprehensive process, we’re able to provide a complete, long-term solution.

Keep Mice Out Of Your Niagara Home For Good!

The sudden appearance of mice in your home often signals a larger problem waiting to escalate. While it’s tempting to rely on quick fixes like traps or store-bought poisons, these methods fail to address the root of the issue or prevent re-infestation. A lasting solution requires identifying how and why mice entered your home in the first place—and making sure they can’t return.

If you’re hearing scratching sounds in your walls, spotting droppings, or suspecting a nest, don’t wait to take action. At Skedaddle, our experienced technicians are trained to locate and eliminate mice from your home humanely and effectively. With over 30 years of experience, we know how to keep your home mouse-free for good.

Contact Skedaddle in Niagara today to schedule your home assessment and take the first step toward a mouse-free future.