Almost every hen I lost to hawks was in the middle of summer. I only remember one time finding a plucked carcass on the snow in the winter. If you have a lot of hawks, they quickly figure out that chickens are easier to kill and make a nicer meal than a field mouse! I only have Red Tailed here, which are big. I don't know anything about the small hawks and falcons.
If you can plant more shrubs and trees in your yard, that is the best thing. The chickens learn how to hide underneath cover. Also having a few lawn chairs and a table, even if you just put them out while the chickens are out. My grandmother used to set out a few opened umbrellas in the yard and the chickens learned to dive underneath the umbrella canopy if a hawk soared over. I know it stinks to clutter up your hard with "junk" but the more hiding places you have, the better. I have watched hawks dive at my chickens but the chickens duck under a bush and the hawk aborts their dive and goes back to the sky. If the chicken had been in the wide open, they would have been dead.
Spring is a great time to find some nice sales and deals on shrubs. If you pay a little more money, you can get bigger ones that are nicely leafed out already.
Originally Posted by Henway Park
I think the best approach is to wait until spring to free range. Despite having lots of hawks around, I had no problems with free ranging until winter. I think the lack of cover and limited supply of food makes the chickens an attractive target. When the chickens have plenty of cover, and the hawks have more easily available prey, chickens are farther down on the menu. I'll let you know how this theory works for me in June. Good luck.