Hi there.
Sold in the equine section... also works on mosquitoes, poultry lice, fleas and other pests... mosquitoes is what I bought it for. It is sold under many names and in different concentrations (Gordon's, Permethrin 10, etc.). The one pictured is ready to use. The active ingredient is Permethrin... said to be a synthetic form of pyrethrin, a chrysanthemum extract.
Safe for use in chickens, with no withdrawal time needed for eggs.
Also for use on walls, in the lay box, coop floor, under roost, and so on. Not safe for use with cats. But labeled for use in many creatures including dogs, goats, and so on... this bottle cost under $8 and lasted me 2+years with 82+ birds, 2 large goats, and 3 medium dogs.
I bought the first one on the following link and it works quite well...
https://www.peststrategies.com/reviews/fly-products/best-fly-traps/
The penny in the water bag is bull and not effective at all. I have seen it used at restaurants where the fly literally landed on the bag with the penny. Actually I can say the same about mosquitoes and mint or other type plants... saw them land right on the whole bush. Those work best as deterrents when fresh cut more so than just growing them.
I also leave my (dog/chicken) droppings in an old dog food bag open to be fly blown during the daytime and close it up and dispose of it about dusk (no more flying activity) with all the new (eggs) larva inside it heads of to the dump. Since I don't have major issues I only tie it up weekly. But doing so daily is ONE way the wildlife rehab center/zoo I volunteered at kept them down.
Interestingly... when I do pick up my dog (or pig) droppings they are often loaded with beetles and other things already consuming any nutrients and breaking down the material even further. So cool that what is often considered a pest is actually an integral part of life... and actually helps to keep disease at bay... when in balance.
I know how annoying flies can be though, as evidenced by the fact that I have actually BOUGHT fly traps... I have a HARD time spending money. Squeak!
For baiting homemade bottles... flies seem to like potatoes... which when they start to rot can smell just as bad as any meat, but it seems to attract them even before that.
Since we can't change the standard environment or what our neighbors might be doing... we just do our best. But this is an ongoing seasonal battle that you must follow through, even if every couple days... if the fly load is important to you.
Some of us even set up maggot buckets where the flies blow (lay eggs in) a piece of old meat, fat or whatever and then the maggots crawl out to pupate and get gobbled up by our birds. The species and weather I have here mean the maggots are so small, it is not an effective means of control for me might be worth considering for you.
Okay one final thought on keeping flies at bay if not abating them... fans work wonders.
So many folks have been dealing with buffalo gnats this year... a type of biting fly. They have even lost entire flocks to them.
Hope this is helpful some!
