Many people believe the risk of tick-borne diseases disappears entirely once cold weather arrives. While tick activity changes with the seasons, the risk of encountering ticks does not vanish in winter. Understanding how ticks survive and remain active during colder months is important for year-round awareness.
How Ticks Endure Cold Temperatures
Ticks are highly adapted to survive cold conditions, employing several biological and behavioral strategies. They enter a low-energy state where metabolic activities are significantly reduced, conserving energy.
Ticks can modify their internal chemistry to withstand freezing. Some species reduce the water content in their cells, lowering their freezing point and preventing cellular damage. Certain ticks, such as Ixodes scapularis, also produce “antifreeze” compounds that protect them from extreme cold.
Ticks seek shelter in insulated microclimates. They burrow into leaf litter, soil, or dense vegetation, shielding them from direct exposure to freezing air. Snow cover can also act as an insulating blanket, maintaining a more stable and warmer environment.
Tick Activity in Winter
Despite cold temperatures, ticks can remain active or quickly become active when conditions are favorable. Black-legged ticks, also known as deer ticks, are a notable example; adults can be active any time temperatures are above 40°F (4.4°C), even with snow on the ground.
Mild spells or brief thaws during winter can trigger renewed tick activity. When the ground thaws and temperatures climb above this threshold, dormant ticks can emerge from their sheltered locations to quest for a blood meal.
While black-legged ticks show considerable cold tolerance, other species may behave differently. American dog ticks and Lone Star ticks tend to become inactive at higher temperatures and are less likely to be encountered during colder months. However, the overall trend of warmer winters can lead to an extended period of tick activity and expansion into new areas.
Staying Safe from Ticks Year-Round
Preventing tick bites remains important throughout the year. When spending time outdoors in wooded or grassy areas, wearing appropriate clothing provides protection. This includes long-sleeved shirts and long pants tucked into socks or boots, with light-colored clothing making ticks easier to spot.
Using EPA-registered insect repellents containing ingredients like DEET, picaridin, or permethrin on clothing and gear can deter ticks. Permethrin-treated clothing offers lasting protection through multiple washes. Always apply repellents according to product instructions.
Upon returning indoors, it is important to conduct a thorough tick check on yourself, family members, and pets. Pay attention to areas like the scalp, behind the ears, under the arms, and around the ankles. Prompt removal of any attached ticks can reduce the risk of disease transmission.
Maintaining your yard can also help reduce tick habitats around your home. Removing leaf litter, keeping grass trimmed, and creating barriers of wood chips or gravel between lawns and wooded areas can limit tick presence. Moving woodpiles away from the house also helps eliminate potential hiding spots for ticks.