I told my friend I was really looking forward to the cold weather and winter because it will finally mean no more bugs inside the house. He says I’m nuts, that there are always indoor bugs no matter what’s happening outside. Is that true, don’t they die off or something? L. L., Framingham, MA

It’s true that you won’t have insects coming into your home from outside in the dead of winter, but many of the insects already inside will continue to prosper. There are plenty of insects and other creepy crawlies that are strictly indoor pests: German cockroaches, stored food beetles and moths, bed bugs, clothes moths, carpet beetles, silverfish, drain flies, even fleas. All can continue with their life cycles throughout the winter indoors as long as they continue to have a food source and temperatures remain moderate. See What Happens to Indoor Insects in Winter?

Of course you won’t see all of these insects in your home in the winter just like you don’t see most of them the rest of the year. But they’re there. A recent research study found that the average home has 100 different species of insects and arthropods present at any time, most of them unseen. See Don’t Read This if You Don’t Like to Live with Bugs!

MOST INDOOR INSECTS JUST KEEP DOING THEIR THING

And as long as you have these insects in your home, you will no doubt have predators that feed on insects such as spiders and house centipedes. Admittedly, reproduction and growth rates for some of these pests may slow down some in winter simply due to cooler, drier indoor conditions. Most insects and other pests do better and are more active in hot, humid summer conditions. The feeding activity of carpenter ants and wood-boring beetles that may be hidden in walls will slow down some and termites who actually live in the frigid soil but feed on your home will be temporarily inactive during cold periods. But then you never saw these insects anyway.

YOU MIGHT HAVE EVEN MORE INDOOR PESTS IN WINTER

Some homes will even gain pests in the winter as certain fall-invading insects move inside to escape the cold (see Why Do I Have More Indoor Pests in Winter?). These outside pests such as western conifer seed bugs, Asian lady beetles, and brown marmorated stink bugs may be spending the winter in your attic at this moment. They’ll show up downstairs on the first warm winter or spring day as they try to get back outside. Then there are the larger winter visitors. Mice can be more common in homes in the winter as they move in from outside seeking a warmer place to nest. Squirrels and bats might join the various insects spending the winter in the comfort of your attic.

Now that I think about it, I need to correct the statement in the first paragraph above that said you won’t get any new pest introductions in the cold dead of winter. It can happen if you periodically bring in firewood that is sheltering insects (see A Cozy Holiday Fire Can Mean Firewood Pests). And sometimes, even here in the Northeast, we get a winter thaw that can “awaken” insects that are hunkered down outside, sending them inside.

Sorry, there really is no break from pests, even in the winter. That’s why pest control companies don’t shut down for the winter. So, don’t worry, you can give us a call anytime. We’ll be here!