Are Ticks Active in Winter?

Yes—ticks are active in winter, but their abundance and exploits are tied closely to the temperature. When it’s around the freezing mark, you won’t likely run across ticks when you go hunting or hiking with your dog. But when temps rise just above freezing, ticks will climb a piece of grass in hopes they can latch onto a chipmunk or dog walking past. Letting your guard down against ticks once the cooler weather arrives is a mistake. Here’s what you need to know to protect yourself and your dog from the reviled, blood-sucking critters through the winter:

Understanding Ticks

Ticks are parasitic arthropods (invertebrates with exoskeletons) that feed on the blood of host animals, such as mice, deer, cattle, birds, and humans. They are usually found on grasses, in underbrush, and in densely wooded areas, where they wait for their next host (aka meal) to stroll by so they can hitch a ride. If you live in an area with large populations of mice, chipmunks, and voles, chances are good you live near large populations of ticks who often feed on these rodents.

There are about 900 species of ticks around the world, with just over 90 tick species found in the US. Only a handful of tick species transmit diseases to humans and dogs, but the ticks of concern are pervasive and their territories are widespread.

Ticks carrying diseases in the US include deer ticks, also known as blacklegged ticks; these are among the most notorious species, because they transmit Lyme disease. Other tick species that spread diseases to dogs and people include American dog ticks, lone star ticks, western blacklegged ticks, Rocky Mountain wood ticks, brown dog ticks, and Pacific Coast ticks. The diseases these tick species carry include Lyme Disease, Rocky Mountain spotted fever, babesiosis, Southern tick-associated rash illness (STARI), and ehrlichiosis.

All of these illnesses require treatment to prevent serious, possibly fatal, complications.

Are Ticks Active in Winter?

The risk of tick bites is highest from April through September, according to the Centers for Disease Control and Prevention (CDC). The warm months coincide with the highest populations of ticks and the most active stages of a tick’s life cycle, which is two years.

In the winter months, ticks are far less active than they are in spring and summer. But there is still a chance you’ll pass a tick looking to catch a ride and a meal. Depending upon the species, the critters survive the winter months by going dormant under a pile of leaves or burrowing underground, or by riding out the winter on a warm host animal. But when temperatures rise above 35° F or thereabouts, some ticks will emerge from dormancy to search for a new host.

Climate Change and Ticks

With climate change due to global warming, seasonal respites from ticks have become shorter lived and the geography of tick activity is expanding. As the planet warms, northern US states, such as Vermont, North Dakota, and Minnesota, are experiencing an uptick in mild winter temperatures. This means more winter days with temps above 35° F and more days when ticks are active.

Winter Season Tick Bite Prevention

Between 2004 and 2016, the CDC recorded a dramatic increase in illnesses caused by ticks, mosquitos, and fleas. Reported cases of bug- and tick-related illnesses increased from 27,388 in 2004 to 96,075 in 2016. It’s believed the increase is connected with the expanding habitats and increased populations of these bugs.

For those who enjoy hiking, hunting, or exploring the outdoors with their dogs, protection from Lyme disease and other tick-borne illnesses is a year-round endeavor. Methods of preventing tick bites for you and your dog in winter are exactly the same as in spring and summer, with a few common-sense additions to the list.

Before Going Out:

• Wear long pants and long-sleeved tops.
• Wear light-colored clothing, which makes it easier to spot ticks, especially tiny ticks in the nymph phase.
• Tuck the cuffs of your pants into your socks.
• Outfit yourself with specialized clothing treated with permethrin.
• Use a flea and tick collar on your dog and/or a topical tick treatment.
• Use EPA-registered insect repellent on yourself.

When You’re Out:

• Stay at the center of well-worn trails, away from leaf piles and underbrush that are common hangouts for ticks in winter.
• Keep your dog on leash during winter hikes so she can’t run off trail.
• Frequent hikers know some areas are especially “ticky.” Avoid heavy tick zones whenever possible.
• Avoid sitting on the ground, especially in rocky areas or near piles of leaves.

When You Get Back:

• Give your dog a tick check before you go inside the house. Be particularly diligent if you went off trail. If your dog wears a dog coat, check that, too.
• Check your coat, hat, and scarf for ticks.
• As an extra precaution, put your outerwear and clothes in the dryer on hot for ten minutes.
• Take a shower soon after you get home and scan yourself thoroughly for ticks.

If you spot a tick on you or your dog and it hasn’t yet embedded, you can simply lift it off and flush it down the toilet. If you discover an embedded parasite, carefully remove the tick and consider storing it in a glass container until you can get it tested for tick-borne illnesses.

Another effective strategy for tick bite prevention in all seasons is creating a tick-unfriendly zone around your home. This is particularly important when you have an enclosed backyard where your dog spends time playing and exercising year round. Here are steps to take:

• Keep the woodpile as far from your house as possible, and out of your dog’s usual play area.
• Keep your grass mowed short.
• Don’t let leaves or sticks collect near the house.
• Put up fencing that prevents deer from grazing on your property.
• Close up small holes around your property—they make appealing dens for rodents, which are tick magnets.

No matter where you explore the outdoors with your dog (Central Park or a national park), or when (July or January), it’s important always to be watchful for ticks. If you make tick prevention part of your daily routine year round, you’ll significantly reduce the risk of a tick biting you or your dog.