Living on a farm there's plenty of flies. Not only was there flies on the porch where the chicks are, but there was flies everywhere. It's a common practice in this area to dump used chicken litter from the commercial houses on the meadows to help the bermuda grass grow. Talk about flies! Anyhow, I bought these fly traps at Walmart, sold under the brand name Rescue. They consist of a plastic yellow trap that you attach to the included plastic bag after you fill it with water. The bag contains a dried chemical. I hung one on the porch where the chicks are and one outside the back door. There is not A SINGLE fly anywhere near the chicks, nor are there any in the house. The one outside the back door has literally hundreds of flies trapped in it. They've made a believer outta me, so I thought I'd pass this along. It does say not to use indoors due to an odor they give off, but I haven't noticed the odor outside.