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Name: Maureen D
Status: other
Age: 50s
Location: N/A
Country: N/A
Date: 2001363

We live in Cincinnati, Ohio and since the summer, we seem to be inundated with large black horse flies. They eventually end up by the skylight in the bathroom. Some are particularly frisky while others seem to be listless. Do you have any idea what the problem might be? We do not leave food around and the house is spotless. As I mentioned, they gravitate upstairs. The weather has been unusually warm here. When we get a cool spell, should we assume that the flies will finally die? This is the first year that we've noticed them and I would say it started in early September.

Sounds like Domisticus horribilus which hatch during warm periods and live off detritus that cannot be eliminated from a house...very common in country homes.

Peter Faletra Ph.D.
Assistant Director
Science Education
Office of Science
Department of Energy

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