As autumn settles in, bringing cooler nights and shorter days, several insects start seeking cozy spaces for overwintering. Among them are cluster flies, a name that accurately reflects their habit of clustering together in sunny spots on walls or inside your home as they prepare to hibernate.

Unlike some pests that overwinter as eggs or pupae, cluster flies and other insects like Boxelder bugs, multicolored Asian lady beetles, and western conifer seed bugs survive the cold as adults. This necessity to find warm refuge makes them more noticeable as they invade homes during the fall.

The cluster fly, scientifically known as Pollinia rudis, particularly stands out due to its large size and tendency to gather in noticeable numbers, earning less flattering nicknames like “bunch o’ flies.” Although they are similar in appearance to the common housefly—dull black and gray with golden hairs—they are not indicative of poor housekeeping. Instead, their presence is more about the luck of your location and a thriving outdoor earthworm population, on which their larvae parasitize.

Tackling Cluster Flies

Dealing with cluster flies involves the same measures as controlling other fall-time home invaders. This includes ensuring your home is well-sealed with proper caulking around doors, windows, and other entry points, and checking for gaps around utility boxes and dryer vents where pests could enter. Unfortunately, once inside, cluster flies can be quite a nuisance. They may end up in living spaces, attics, or wall voids, and on warm winter days, they might reappear, disoriented and sluggish, near windows.

Targeted Pest Management

While some may reach for the fly swatter, a more effective and lasting solution involves professional intervention. Northern Pest offers specialized control strategies that not only address cluster flies but also provide preventative measures against future invasions. Instead of battling pests on your own, consider enlisting expert help to ensure your home remains comfortable and pest-free this season.

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Northern Pest: Our family serving yours! We are licensed and insured to provide insect and wildlife pest control. Our crew has the expertise to track wildlife entry points and remove pests of all kinds, including our licensed builders, who can make any of the necessary repairs caused by wildlife. Northern Pest is a member of the MDAT and the NWCOA. We are certified by the IICRC to offer professional mold mitigation services caused by animal damage. At Northern Pest, we do it all!

Written by the Digital Marketing Team at Creative Programs & Systems: https://www.cpsmi.com/.