Flies with green bodies on brewing patio

[bioguy]

Anybody ever have house-flies with green bodies congregating where you brew outdoors?

I built a patio to brew on last summer and didn't have any problems with flies. This year, they are really thick--like 10 per square foot in places. I'm wondering if they're attracted by spills and boil-overs. I'm planning on putting out fly traps. I searched the forum, but only found fruit fly issues. Any help would be appreciated.

Posted here since I figure it is a sanitation issue.

 

[maida7]

could be a dead body nearby. Find the dead animal and remove it and the flies should decrease.

 

[blefferd]

They are probably attracted to the wort like you said, I have a huge problem with them when I brew in my garage. If you dont have pets in your yard they are probably coming from someone elses place/yard/garbage. Any farm land near by? If you have pets in your yard clean up the waste, you can also go organic and buy these little creatures called fly preadators. They are living insects that eat fly larva. They come looking like dried up maggots and you sprinkle them in the problem areas of your yard. A couple applications of them should be plenty to get them established.

Other than traps, posion and cleanliness nothing you can really do about them other than keep them out of your finished wort.

Oh by the way those flies with blue/green bodies are not common house flies, those are blow flies, usually seen on dead bodies, **** or very rancid garbage with rotting food in it.