why do people hang bags of water outside?

Question

i was told it was to deter flies... if so how does it work?

Answer 1

You are right, it is to deter flies.

I have read that the water bag acts like a lens that reflects the movements of people, objects, etc. in the area. Even if the fly is too far from the action to see it directly, it can see a shifting of light and dark in the water bag, which it interprets as nearby movement, and it will fly away from the bag.

Answer 2

I tried it outside my back door. I didn't see any flies hanging around, during that time, so maybe it worked? There is supposed to be something about the visual appearance of the water that deters them...it's what I was told.

Answer 3

Hang Bags

Answer 4

i've heard that to a fly, the ziploc bag of water will look like a spider web, thus detering them. Although, i've seen flies land right on it, and i think they busted that myth on mythbusters of something like that.

Answer 5

You are supposed to add a penny or marble to the bag of water to look like a spider sitting in a web to any insect with compound eyes (flies, bees, wasps).

Answer 6

I see this in little restaurants and stuff. I think it has something to do with the flies reflection in the water. They see their big distorted reflection and the fly away. This is just my thought though, I could be entirely wrong...

Answer 7

I'm not sure why it works, but it does. I do it at my house. Even the grocery store in our hometown does it, it has got to be something to do with the reflection the water gives off, but I'm not sure exactly what it is.

Answer 8

I've never heard of that.