Ticks have survival strategies that allow them to remain a threat throughout the year, meaning the assumption that cold weather ends the risk of tick exposure is incorrect. Tick activity levels fluctuate based on ambient temperature, not strictly the calendar season. While peak seasons are spring and summer, the risk does not vanish when temperatures drop. Understanding how ticks survive cold conditions is necessary for year-round protection.
When and Why Ticks Remain Active During Winter
Ticks do not enter a true hibernation state but instead become dormant when temperatures are consistently low. This allows them to reactivate quickly during mild spells. The main species of concern in late fall and winter is the adult blacklegged tick (Ixodes scapularis). This life stage is most active when searching for a host in the cooler months and will readily emerge again in winter when conditions allow.
The adult blacklegged tick can become active and search for a host any time the temperature rises above approximately 35 to 40 degrees Fahrenheit (2 to 4 degrees Celsius). A sunny afternoon or a brief warm front can be enough to trigger them to emerge from their protected spots. Although larger than the nymphal stage, adult ticks still pose a danger. They are capable of transmitting pathogens like the one that causes Lyme disease while questing for a blood meal.
Where Ticks Hide During Cold Periods
Ticks survive freezing temperatures by seeking out microclimates—small, localized areas with milder conditions. The most important of these is the layer of leaf litter found on the forest floor. This organic material acts as a natural insulator, trapping ground heat and moisture. This protects the ticks from both extreme cold and drying out.
A layer of snow also provides protection for ticks sheltered within the leaf litter or just below the soil surface. Snow acts like a blanket, preventing the ground temperature from dropping to the low air temperatures above. This insulation maintains a stable, near-freezing environment at ground level, allowing dormant ticks to survive. Ticks often seek out sheltered, sunny spots on the edges of wooded areas to quickly warm up and begin questing during a brief thaw.
Winter Tick Prevention and Safety
To minimize risk during winter outdoor activities, apply specific preventative measures, even for a short walk in a wooded area or yard work. Treating clothing and footwear with the insecticide permethrin is a highly effective strategy for deterring ticks. Permethrin bonds to fabric and causes a “hot-foot” effect, leading ticks to quickly fall off before they can attach.
When dressing for outdoor activities, choose light-colored clothing, which makes the dark bodies of ticks easier to spot. Upon returning indoors, a thorough tick check should be performed on all people and pets. Pay close attention to areas like the waistline, scalp, and around the ears. Any clothing worn outdoors should be placed in a hot dryer for five to ten minutes before washing, as high heat is effective at killing any clinging ticks.