Part 2: Winter Pests in Iowa – The Ones You Don’t Expect

In Part 1, we covered why winter pests move indoors and why mice are the most common cold-weather invaders in Iowa homes. In Part 2, we’re shifting focus to the other winter pests homeowners often overlook: insects, spiders, bats, raccoons, and even the bugs that hitchhike in on firewood.

These pests may be quieter than rodents, but they can still create damage, stress, and health concerns throughout the colder months.

Insects

Most insects survive winter in one of two ways: migration or diapause, a form of dormancy triggered by shorter daylight hours. Many overwinter underground, beneath tree bark, or in leaf litter. Others, especially wasps,choose human structures for shelter.  Here’s an interesting twist: the only wasps that survive winter are fertilized queens. The rest of the colony, the workers you see buzzing around in summer, die off with the first hard freezes. Those lone queens spend winter hidden in wall voids, attics, and eaves, waiting for spring.  But there is a long list of bugs that do manage to survive winter, ,and typically in your home.

Common winter insects in Iowa homes include:

• Boxelder bugs
• Cluster flies
• Lady beetles
• Stink bugs
• Spiders

Even dormant insects can become active during warm spells, appearing in windows, walls, and living spaces. While they may not be dangerous, they’re disruptive and often arrive in large numbers.

Bats

Bats commonly enter attics and wall spaces in search of safe winter roosting areas. Signs of bats include:

• Guano (droppings)
• Dark staining near rooflines or vents
• Scratching or rustling sounds

Bat removal and exclusion must be done humanely and in compliance with Iowa wildlife regulations. Improper removal can harm protected species and leave you with lingering odor, contamination, or structural issues.  Typically, Bats do their own version of hibernation over the winter called torpor, where their body temperature, heart rate, and metabolism drop to conserve fat reserves until spring, but if temperatures rise as they did last year, you may hear scratching or movement between the walls on warmer days. 

Raccoons

Raccoons don’t fully hibernate and frequently seek shelter in:

• Attics
• Chimneys
• Under decks and porches

They are strong, intelligent, and persistent. Once inside, raccoons can tear insulation, damage ductwork, and create costly repairs while nesting.

Firewood Pests

This is where you might accidentally bring the pests to you!  Bringing firewood indoors often brings in more than warmth. Common firewood pests include:

• Ants
• Beetles
• Termites

To prevent firewood pests:

• Keep firewood at least three feet from your home
• Store it off the ground
• Stack it away from trees

Never store firewood from questionable locations indoors

Squirrels

Squirrels are surprisingly common winter pests in Iowa homes. As trees lose their leaves and temperatures drop, squirrels look for safe, dry places to nest. Attics, soffits, and wall voids offer everything they need.

Signs of squirrels in your home include:

• Loud scurrying or thumping sounds, especially in the morning
• Chewed fascia, vents, or roof edges
• Insulation pulled into nesting piles
• Entry holes near rooflines or eaves

Unlike mice, squirrels are active during the day, which is why homeowners often hear them running or dragging materials overhead. Once inside, they can cause serious damage by chewing wiring, tearing insulation, and widening entry holes so other animals can follow.

Trapping without sealing the entry point almost guarantees another squirrel will take its place. Effective squirrel control focuses on humane removal paired with professional exclusion to prevent repeat invasions.

How to Prevent Winter Pest Problems

Outside your home

• Seal cracks in siding, foundation, and rooflines
• Trim shrubs and branches away from the house
• Remove rotting wood, old furniture, and debris
• Store firewood away from structures
• Keep trash bins clean and tightly closed

Inside your home

• Maintain regular cleaning routines
• Keep kitchen surfaces free of crumbs
• Reduce moisture in basements and attics
• Store clothing and shoes in sealed containers

Inspect common pest “hot spots” regularly

Year-Round Pest Protection

Winter pests don’t disappear on their own. Once they settle in, removal becomes more difficult and more expensive. That’s why prevention matters.

Bats and Bugs Pest Solutions offers monthly and every-other-month pest control services tailored to your needs. Our team protects against rodents, insects, and wildlife year-round, before small problems become major infestations.

If you’re noticing signs of insects, spiders, bats, raccoons, or other winter pests, contact Bats and Bugs Pest Solutions. We’ll help keep your home protected through winter and beyond.