20 Common Winter Pests That Invade Homes and Yards

When you hear the word “pests,” you most likely think of bugs and other critters that might bother you in the summer. While it’s true that some pests are more common in the warmer months, the cold won’t stop many of them. In fact, the warmth of your home might end up being very attractive to pests during the winter. In this article we’ll look at 20 of the most common winter pests that could make their way into your home, as well as the damage and problems they might cause.

Top 20 Winter Pests That Might Invade Your Home and Yard

1. Mice

image: Pixabay.com

It’s a common misconception that mice hibernate in the winter, as some rodents do. Mice are different, though, and they’re active all year long. During the winter months, a warm house can be a very attractive place for a hungry mouse. In addition to warm shelter, your house is also full of food. Mice may chew through wires and walls, and can contaminate your food with their droppings.

2. Rats

Much like mice, rats are active all year and will be especially drawn to warm, dry, food-filled homes in the winter. Rats tend to be most active in summer and fall when they’re stockpiling food for winter, because they need to eat much more food in winter to avoid losing too much weight. They’re still active in winter, just harder to notice because they become more sedentary. They generally cause the same problems as mice.

3. Boxelder Bugs

Boxelder bugs feed mainly on trees, but in the winter they seek out dark places to hibernate. When they do this inside your home, your heating system disturbs that hibernation, tricking them into thinking it’s spring and making them active. They don’t bite people, by they can stain upholstery with their feces and can cause damage to houseplants.

4. Stink Bugs

Stink bugs commonly enter homes to spend the winter sheltered from the worst of the weather. Once inside, a stink bug will release pheromones that attract other stink bugs to the area. The biggest problem with stink bugs is that your heater may trick them into thinking that it’s spring already, and they’ll become active. They’re harmless, but the smell they produce when disturbed can be a nuisance. In my house, both Boxelder Bugs and Stink Bugs are the most common winter pests.

5. Squirrels

Like rats and mice, squirrels don’t hibernate in winter – they just become less active. They stockpile food in the warmer months so that they don’t have to forage in winter. Those stockpiles may be dug into your yard, tearing up your lawn and potentially damaging the plants. Squirrels in the attic can also create quite the racket when they run around.

6. Bats

image: Pixabay.com

Bats hibernate periodically in the winter, waking up occasionally on warmer nights to feed. Your attic is an ideal hibernation spot for them: it’s warm, dark, and free of predators. Unfortunately for you, a bat roost in the attic will lead to lots of unsanitary bat droppings. Those droppings can be very pungent, too.

7. Cockroaches

Cockroaches are cold-blooded, and so they don’t like the cold. It so happens that they’re most comfortable at the same temperatures that we’re most comfortable in, and that means that, in winter, our homes are ideal cockroach shelter. Cockroaches spread diseases like salmonella, typhoid, gastroenteritis, and even plague.

8. Fleas

image credit: Olha Schedrina / The Natural History Museum | Wikimedia Commons | CC BY 4.0

Fleas can’t survive freezing temperatures, but they also don’t hibernate. Instead, they’ll just ride your pets warm fur coat right into your home, where they’ll stay all winter long. Fleas don’t just bite your pets, they can also bite you. A winter flea infestation can lead to months of itchy bites.

9. Bed Bugs

Bed bugs can be a huge problem in the winter, because so many of us travel for the holidays, and the bugs just hitch a ride with us. Fortunately, bed bugs aren’t major vectors for any diseases. Unfortunately, their bites are still very uncomfortable and the bugs themselves are notoriously difficult to get rid of.

10. Spiders

image: Pixabay.com

Spiders are common in the home year-round, although many species tend to breed in the fall which means your house might see a population boom in the winter. The American House Spider, Black Widow, Brown Recluse, Wolf Spider, and Hobo Spider are all commonly seen in homes. Some of these are harmless, and even beneficial to have around, while the Widow and the Recluse can be very, very dangerous. Spider bites range from mildly painful to life-threatening, depending on the species.

11. Birds

image: John Winkleman | Flickr | CC BY 2.0

Not all birds fly south for the winter, and of course plenty of people live in the places they migratory birds fly to, so no matter where you live, birds may pose a problem for you in the winter months. Pigeons, sparrows, grackles, and crows are all common winter birds in the U.S. Nesting birds can clog up your gutters and can actually cause structural damage, as their droppings are acidic.

12. Moths

Moths can infest both your pantry and your closet in winter. More accurately, moth larvae can do that. Moths themselves don’t eat your clothes, but the larvae can and do. You may also find them in the dry goods (pasta, rice, etc) in your pantry.

13. Termites

Termites in the home are not usually affected by cold temperatures, which means they can go right on eating up your walls all winter long. In fact, the problem may be worse during the winter, as they won’t be inclined to look for more food sources outside the house and they may start tunneling more.

14. Ladybugs

Ladybugs congregate to hibernate in large groups in winter, and they can do this inside your home. While they’re generally harmless, when they’re disturbed they often release small amounts of their own blood, which is yellow and produces a foul smell. It can stain your walls quite easily.

15. Firewood Bugs

Many different insects can infest your firewood such as ants, termites, click beetles, wood boring beetles, and more. When you bring firewood inside, these pests are free to infest your home. Any bug that can get inside your firewood can do damage to the structure of your home.

16. Raccoons

It’s not uncommon for raccoons to find their way into attics and crawlspaces, and during the winter they’re likely to spend much more time there, and less time outside foraging for food. They don’t hibernate, but they are less active. They’ll happily dig through your garbage for food if they can, and they’re a common carrier for rabies.

17. Flies

image: Pixabay.com

Fruit flies and house flies can become a real nuisance in winter. Flies can’t survive the cold weather without finding a warm shelter, and your home is both warm and filled with things that flies can eat. Luckily, the flies that are in your house are generally harmless – they don’t bite and they rarely spread disease. They are, however, very annoying and they can certainly make you feel like your home is filthy. Check out this article for some ways to repel flies.

18. Centipedes

Centipedes enter the home for the same reasons most other pests do- they’re looking for a warm place to stay for the winter. Most centipedes are harmless, even if they are extremely creepy. All centipedes can bite, and some produce a bite that’s as painful as a bee sting. Some bites may be significantly worse than that, especially if you’re allergic.

19. Silverfish

Silverfish are harmless to people, but they can damage carpets, clothing, furniture, paper, books, photos, and wallpaper. They can also eat the food in your pantry like oats, flour, beef jerky, etc. They’re active all winter as long as they’re warm, so once they’re in your house, they’ll be eating your stuff till spring.

20. Carpenter Ants

image credit: Richard Bartz, Munich Makro Freak | Wikimedia Commons | CC BY-SA 2.5

Carpenter ants can be drawn into your home in all the same ways that other ants are- mostly food left out or spilled. The difference is that carpenter ants are active all year, and so they can still be a problem in the winter. Like termites, they can infest and damage the wooden parts of your home.


6 helpful tips to prevent winter pests from getting into your home

1. Seal your home up tight

Gaps in windows and doors, around chimneys and vents, or between the roof and the walls can allow all sorts of pests, from insects all the way up to bats and raccoons, into your home. Thoroughly inspect your home in late summer or early fall to identify and seal these gaps. Products like this waterproof sealant can seal smaller gaps.

2. Store firewood 20 feet from the house

Keeping firewood right by the exterior wall can make it easy for pests to move from the wood to your home. Keep firewood racks at least 20 feet from the house, and cover it to keep the wood dry, which also helps prevent some pests.

3. Keep your storage organized

Rodents love clutter. Keep your pantries, closet, basement and attics well organized and avoid leaving boxes on the floor. Clear plastic airtight storage bins, like these on Amazon, are essential for this.

4. Put screens on vents and chimneys

It won’t do you any good to seal up the space around vents and chimneys if the vents themselves are open. Place screens over all openings, like this one that’s specifically made to keep wildlife out of your house.

5. Install door sweeps

A good door sweep will help to ensure that pests can squeeze in underneath the door, and they might help the energy efficiency of your home at the same time.

6. Replace old weather stripping

Weather stripping wears out over time. Replacing it can help prevent pests from finding a way into the house. New weather stripping like this one from Amazon should do the trick.