The Cold Truth: Rodents Don’t Hibernate

As winter takes hold across Southern Ontario, many homeowners assume that pest problems are safely behind them until spring. However, this is a misconception that can lead to unexpected infestations. Winter is a peak season for rodent intrusion, as mice and rats actively seek warmth, food, and shelter indoors.

In cities like Hamilton, Burlington, and Oakville, where temperature drops and snowfall are common, rodent activity increases behind walls, in attics, basements, and crawl spaces. Understanding how and why rodents enter homes during the cold months is essential to preventing structural damage and health risks.

Why Rodents Target Homes in Winter

Rodents are opportunistic survivalists. When outdoor conditions become inhospitable, they instinctively seek warmer environments with reliable food and nesting options. Homes, garages, and sheds offer ideal shelter.

Key drivers for rodent entry during winter include:

  • Dropping temperatures that make outdoor survival difficult

  • Reduced natural food sources such as seeds and insects

  • Easily accessible entry points like gaps around doors, vents, soffits, or foundations

  • Indoor food and water availability in kitchens, basements, or pantries

Rodents only need an opening as small as 6 mm to gain entry. Once inside, they can build nests in insulation, wall voids, or stored boxes, often going undetected for weeks or months.

Common Rodents Found Indoors

During the colder season, the most common intruders in Ontario homes are:

  • House Mice (Mus musculus): These small rodents are highly adaptable and often nest inside walls, ceilings, or behind appliances.

  • Norway Rats (Rattus norvegicus): Larger and more aggressive than mice, they burrow under foundations and may cause severe structural damage.

  • Roof Rats (Rattus rattus): Although less common, they may enter attics and upper floors through vents or gaps in the roofline.

All three species reproduce rapidly. A single pair of mice can produce dozens of offspring in a few months, leading to a widespread infestation if not addressed early.

Signs of Rodent Activity

Homeowners should remain vigilant for these signs of rodent intrusion, particularly in the colder months:

  • Droppings near food storage, baseboards, or in cupboards

  • Scratching or scurrying sounds in walls or ceilings at night

  • Chewed wires, insulation, or food packaging

  • Greasy rub marks along walls or baseboards

  • Strong, musky odours in enclosed areas such as crawlspaces or attics

The earlier an infestation is detected, the more effectively it can be managed before significant contamination or damage occurs.

Health and Property Risks

Rodents are more than just a nuisance. Their presence poses serious health and safety concerns:

  • Disease Transmission: Rodents can carry pathogens such as hantavirus, salmonella, and leptospirosis, which may be transmitted through urine, droppings, or bites.

  • Allergies and Asthma: Rodent hair and dander can worsen indoor air quality and trigger allergic reactions.

  • Fire Risk: Rodents often chew on electrical wires, increasing the risk of house fires.

  • Contamination: Food supplies, preparation areas, and stored belongings can be contaminated by droppings or nesting material.

Winter infestations may also be more difficult to detect as activity occurs in hidden areas where rodents can remain undisturbed for long periods.

Professional Rodent Control by Action Pest

For homeowners in Hamilton and the surrounding region, Action Pest offers licensed, discreet, and effective rodent control services during all seasons—including winter. The company provides a thorough inspection of the property, identifies entry points, and implements integrated pest management (IPM) solutions that include sealing gaps, baiting, and sanitation strategies.

Preventative treatments and exclusion work are especially important during winter months when rodents are most motivated to invade indoor environments. With a proven track record and commitment to safety, Action Pest ensures that homes remain rodent-free even in the coldest weather.

If signs of rodents are present—or if you want to protect your home before they appear—contact Action Pest today at 905.318.1242 or visit actionpest.ca to schedule an inspection.