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Entomology (Study of Bugs)/flies sitting on the ceiling


looking at vacant properties yesterday and the ceilings in several rooms were littered with hundreds of black, larger flies, few or them were crawling but not many.  they were about 1cm long and black; the house had no windows and lots of daylight though it did'nt have any dampness visable (though it did smell like mud outside as we walked up to it); no noticeable carcasses or food sources nearby.  what are they doing and how to clear them out with least number of them escaping to breed again, please. Amittyville Horror house came to mind.  
Thank you

Hi Stephanie
Spontaneous populations of flies is not uncommon and their source is often hard to find. But it is a fact however that there has to be a hatch of pupae from a batch of maggots feeding on some decaying material. This could have occurred a week or two ahead oh the hatching either inside of the building or outside. Fortunately the life span of the fly is only a few days and they will be gone. I would simply vacuum them up. Do not be concerned about them escaping and breeding. You cannot control insects outside and besides flies are important in recycling organic material

Entomology (Study of Bugs)

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Walter Hintz


I can answer any questions about insects and spiders.


I have taught science for over 57 years. I am presently teaching biology at the college level. I have done extensive graduate work in entomology.

Momentum Magazine The Ohio Journal of Science

B.S. In Ed Kent State Unuv M.Sc The Ohio State Univ National Science Foundation Fellowships: Electron Microscopy Univ of California Entomology Kent State Univ

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