I've free ranged successfully for years with no losses from free ranging....except for a stubborn pullet that liked to roost in the barn at night and got picked off by an owl.
1: Good, full-time free ranging dogs inside a perimeter fencing of their own or a way to keep them contained to the area in which the chickens free range. I use wireless electric containment and have for many years now...the original fencing system has paid for itself over and over for keeping my dogs safe and keeping my chickens with full time guardians around their range and coop.
2: Plenty of duck and hide areas...trees, lumber piles, barns, even fence rows are places a hen can duck and hide near or under.
3: Good, vigilant roo to call a warning.
4:Flighty breeds/chickens that aren't so tame they don't run at threats from above. If you are constantly stooping to pick up your hens and all they do is squat when you do this~they won't run when a shadow from above stoops on them either. Stop picking up your hens willy-nilly and expecting them to be so tame they don't run away from a perceived threat. They need this survival skill if they are to free range successfully.
5: Perimeter fencing if you can afford it....just to keep the casual dog out, keep your chickens from the road and from the neighbor's yard.
6: If you can't afford any of these, invest in electric poultry netting fencing that you can move easily to fresh range...they make them, they last a good long time, they are easy to move and reposition...and will keep 4 legged preds away, though probably not your hawks unless you also range a dog inside that electric fencing.
