We tried free ranging a couple years ago and lost one of our hens right away. It just didn't come to roost and we never did find out what became of it. That is the only one we have lost to a possible predator. The neighbors have all had a slaughter at one time or another due to both raccoons and mink, so we decided to tighten up the habitat and put up a 300 ft electric poultry mesh perimeter around an outdoor ranging area and the coop with attached run. We tried to make the coop and run impervious to everything from mice to coyotes. We have hawks and owls in the area, but so far they have not bothered our large breeds while ranging during the day. Raccoons, possums etc. are easy to trap and can be controlled fairly well. The most feared critter around here among the chicken wranglers seems to be the abundance of weasels, both long-tailed and mink. They are smart predators, tough to control and once in the coop will kill at will.