Question- Do green bottle flies or houseflies eat fruit? Like off the tree, breaking the skin? I live in the city and my neighbor has fruit trees, though he hasn't had them for many years and we are having a very moist year for this area. He says the flies are ruining tons of his fruit, he only has a few trees though, and showed me one tree that did have a couple of flies in it. But it also had other bugs on it. He claims my newly acquired duck pen this year is the problem....I don't think flies do that in their natural cycle- not unless its overly ripe. So am I wrong? My duck pen is messy- I try to put bedding in it and have a kiddie pool that I change the water of everyday and try to put most of the water out of the pen, and rotate spots so the ground does get a chance to dry. My other neighbor does not claim to have any problems with extra flies in their yard, but complain of an odor sometimes..... I can't give them more space right now because I need a fence, though they do get to run around the yard for a few hours everyday. And I don't actually live on the property with them but across town in an apartment, so they can't stay out longer. I am hopefully moving out to the country and buying a house.