I know many people have not had success with shiny objects hanging but I can tell you, when you put out enough and they are of different types, the shining and moving can be a good deterrent... I didn't believe it either but it's worked well for me. The hawks might fly over but they will never come close to the ground- they do make me crazy but that's not their fault, they are just being who they are. I also got 2 owls that respond to motion and also turn their heads and light up when disturbed. They work as long as you
move them around frequently. Hawks are very smart but with a little effort, you can bluff them. I bought some very inexpensive scarecrow decorations from
Walmart and put them in a different place every time I am going to let the hens out, another tool that seems to work.
They truly don't like loud, sudden noises but they don't care if an old lady is yelling at them! lol Bottle rockets can cause a lot of problems, including hitting the bird (see what I said further down) and setting your area on FIRE, even if it isn't dry. If you do own a gun, of any type, they will flee rapidly if they hear a gunshot. If you are comfortable with firing one, just shoot into a hay bale or something else that can catch the bullets. You would be surprised how fast they will flee.
I keep my hens in closed runs attached to their coops and they have solid roofs. They enjoy the sunshine since it comes in from the side. I also use sand bedding which has been far easier to clean and they seem to really like it for dust bathing. Any treats and all food and water are only available in the coop or run. Because of this, they love to stay put and are seemingly quite content. I do let them out for about 10 minutes per day just to have some grass/bugs and scratch around, with me walking right alongside them, and they return to their coop on their own (but rapidly if I make the magical cheep-cheep noise that indicates snacks).
I now have some guinea hens who have been invaluable with warning if a hawk is nearby, even if I can't see the hawk yet. Some people hate the noise guineas make but they only make it in response to something unusual or a predator- I could put up with that small amount of noise for all the benefits they give (including eating every tick that comes down the pike). Since they are wilder birds they tend to be far more adept at avoiding hawks and every other kind of predator in the daytime, but they also come into their coop after a while and respond to the specific sound I use for their snacks.
Sometimes it's tempting to get angry or scared and think about killing them but you don't know the kind of ongoing legal nightmare you could face, that can go on for years. Try to deter as much as possible. I liked what a previous writer said- your hawks might actually be a group that is migrating since Red Tails look like many other hawks. While they may seem evil, they are just doing what comes naturally and I have to respect that. My job is to make that as difficult as possible. I hope any of this helps, it has been a lot of trial and error to get the results I have now.