Cluster flies

Asked July 11, 2016, 9:49 AM EDT

We had a sudden and unexpected infestation of flies in our house yesterday afternoon. This occurred as we were in the process of cleaning the basement. After some searching this morning, my best guess is that based on the fly behavior is that they are cluster flies. Is my guess correct? That does not make them less disgusting! Please advise a safe and effective method to control this infestation! Thank you!

New Castle County Delaware insect issues insects insect management insecticides household insects

1 Response

I do not think you have cluster flies. The information I have been able to find suggest cluster flies are active in the fall. The image you have provided is slightly dark therefore not quite able to see everything I need to identify the fly via a photo. The fly may be a sarcophagid (flesh fly). It may be possible that during the cleaning of the basement, there may have been a food source they were using that was disturbed. One of the management tools for this group of flies is sanitation since they often feed on dead animals or decaying meat/flesh of some sort. Yellow sticky strips or a fly swatter may be other options for successfully killing the adult flies. I cannot say which fly you have found in your home without actually seeing the specimen. If you wish to drop off a specimen at the 461 Wyoming Road cooperative extension office, then I will look at the insect.