Cluster flies are a common occurrence in higher elevations of Colorado, beginning in late summer and extending into the fall. The flies are seeking shelter as the weather cools and they will enter a semi-dormant state until the weather warms again.
Cluster flies are a ½ inch or a little less in length, or just a tad bigger than a common house fly. They tend to be a dull grayish-brown in color, although some have light patches on their abdomen. Their most distinguishing characteristic is tangled, golden hairs on their thorax, near the legs and wings.
They are generally found in areas where there's moist soil, such as near streams and rivers or where lawns are irrigated. The adult flies feed on water and other liquids.
While they are a nuisance, these flies aren't considered "filth flies" and they mostly feed on earthworms found in the moist soils that attract the flies to an area.
As the days grow shorter in mid-August, cluster flies start seeking shelter. You may see them resting on the southern or western walls of buildings, enjoying places warmed by the sun. However, they’ll check the area for entry points, and if there are any cracks, they’ll enter.
Once inside, cluster flies look for sheltered places such as attics or wall voids. They tend to congregate in the upper areas of a building, which is why they are also called attic flies.
Keep Cluster Flies Out
The most important thing you can do to keep cluster flies out of your kitchen and the rest of your home is to make sure any entry points are properly sealed. That means cracks and gaps around windows and doors as well as placing screening over ventilation spaces. Pay particular attention to the southern and western sides of your home, as the flies are mainly attracted to those areas.
Once cluster flies are in your home, your best chance of controlling them is to contact a professional pest control service.
If you need help with cluster flies, contact RAM Wildlife & Pest Management. We have the experience and knowledge required to control cluster flies effectively. Call us today, because it's important to act before the flies have established themselves in your home.