The fly experiment.

[Skinny rooster]

Well... so this year was a record-breaking year for cluster flies. They still are coming out of every nook and cranny in the house but fortunately slowing down in numbers. The last week there was a lot of ice buildup on the upstairs windows and many flies were frozen into the ice. I thought good that they were going to be killed off by the cold. After watching them for days, I was horrified to discover that being frozen had no effect on them. In fact a couple were frozen head first into the ice and survived for days, the ice melted away this morning with the warmer weather and most of the flies were free to walk around untouched (until I got the swatter). I guess that makes sense, cold shouldn't kill them or there wouldn't be a next generation. Not what I was hoping for.

[JP*]

At our place the flies have been bad as well.
Luckily they are easily caught against the windows.

Any tips on how to prevent them in the future?

[Shnookie]

Duck tape on the window sill? It wouldn't prevent them but it might catch some. :)

[Skinny rooster]

At our place the flies have been bad as well.
Luckily they are easily caught against the windows.

Any tips on how to prevent them in the future?

I don't think there is any way to prevent them, you can only manage them. The better you seal up your house the less you will have. They are looking for a warm place to spend the winter and unfortunately that means our houses. I don't like using poison so I hang the sticky coils. One thing new that I tried this year was those sticky plastic sheets you put on your windows, they work great. An old timer told me that if you can slip a piece of paper into a crack, then a cluster fly can fit in and get through, I believe him lol.