The belief that ticks disappear entirely once cold weather arrives is a misconception. Many assume freezing temperatures eliminate these arachnids, making outdoor activities safe from tick encounters. However, ticks possess adaptations allowing them to endure cold conditions, remaining a concern year-round. Understanding how ticks survive and behave in cold weather is important for staying safe outdoors, regardless of the season.
Tick Survival in Freezing Temperatures
Ticks are resilient, surviving surprisingly low temperatures. They employ several biological strategies to endure freezing conditions. One adaptation is dormancy, or behavioral diapause, which conserves energy by suspending typical questing activities. Some tick species also develop natural antifreeze-like substances, such as glycerol, preventing internal fluids from freezing solid. This allows them to withstand otherwise lethal temperatures.
Ticks can survive brief exposures to freezing temperatures, though prolonged exposure below 10°F (-12°C) for several days can be lethal for many species. Survival does not mean activity; ticks become less active when too cold to move effectively. Even in the coldest regions, they persist by seeking sheltered microclimates. Black-legged tick nymphs, for example, survive cold winter temperatures when insulated by leaf litter and snowpack.
When Ticks Are Active in Cold Weather
While ticks survive cold, their activity, particularly questing for hosts, depends on temperature. Many species, especially black-legged ticks, become active and seek hosts when temperatures rise above freezing, often around 35°F to 40°F (1.7°C to 4.5°C). This means ticks can emerge from sheltered spots on mild winter days. Warm spells can trigger tick activity, posing a year-round risk.
Adult black-legged ticks are active during the fall and can continue feeding as temperatures drop. The risk of tick encounters is possible anytime temperatures remain above freezing. Although overall tick activity decreases during the coldest winter months, typically late December through February or March, it is not entirely absent. Ticks attached to warm-blooded hosts like deer can remain active and survive cold snaps, benefiting from the animal’s body heat.
Where Ticks Seek Shelter in Winter
During winter, ticks employ various strategies to find insulated environments protecting them from extreme cold. A common tactic involves burrowing into leaf litter, which provides a protective layer and natural insulation. Ticks also seek shelter under snow cover, which serves as an insulating blanket, protecting them from harsh surface air temperatures. This snowpack creates a stable environment, allowing ticks to thrive beneath it.
Some species may also burrow underground or seek refuge in cracks and crevices of trees or rocks. These sheltered locations, such as wooded areas, dense vegetation, and tall grass, offer ideal hiding spots. Yards can also harbor ticks, particularly if leaf litter is present or if wildlife brings ticks closer to human habitats.
Protecting Yourself from Ticks in Cold Seasons
Protecting yourself from ticks during colder months requires continued vigilance, as they remain active on mild days. Perform thorough tick checks on yourself, your family, and your pets after spending time outdoors, focusing on areas like the scalp, behind the ears, underarms, and ankles. Pets should remain on year-round tick prevention treatments.
Wear appropriate clothing, even when temperatures are low. Covering exposed skin with long sleeves and pants helps prevent ticks from latching directly onto your skin. Tucking pants into socks or boots seals potential entry points, and light-colored clothing makes it easier to spot dark-colored ticks.
Use EPA-registered tick repellents containing ingredients such as DEET or picaridin for added protection. Maintaining your yard by keeping leaf litter and tall grass trimmed reduces tick habitats near your home. Moving woodpiles away from the house and clearing seasonal debris also eliminates favored hiding spots for ticks.