Are they free ranging? If so, you'll need to put them in there coop and run for a week or two. If they are in a run already and the hawk swoops in, you need to cover the run with chicken netting. I'm sorry for your losses and good luck!
All I can suggest is to have a large, enclosed run for the chickens and put a top on it.
If you use a solid material it will give them some respite from rain,snow and even sun.
But a wire top would be good enough to keep hawks, etc. out.
After our hawk attack a month ago. I went to the Dollar store and hung up Mylar balloons.in the bald spots. That pissed the hawk off for 2 weeks until I could get a roof up over the run and netting in the forested free range area... I have a roof over the run and where the bald spots are, in the Forest, I drapped basic plastic netting with zip ties. My girls are not allowed out in the open, unless I'm in the yard with them on weekends or evenings after work. I have 1/4 acre in the forest for them that has basic chicken wire rolled out to keep them in the covered forest for day playtime
My roos let me and the girls know, when danger is peeking in. He sends the girls to coverage while he stays out to take the danger head on. But he is still only 6 months old and learning.. Sometimes he gets it right, and other times, he is distracted by a fluffy butt walking by.. But he is getting better. Just yesterday, I heard him calling for danger in the area, and YEP!! Hawk on a branch over the forest area.. Hawk flew off, without incidents
We have a murder of crows near us and they chase the hawks off. You can hang cds to scare them off and get one of those fake owls but the hawks will figure it out after a while. The best option is to provide plenty of coverage for them to hide. If my girls see a hawk...and they usually see one before I do...they run to safety. Trumpet vines are great cover. If mine can't make it under our porch they run under the vine until they can make it back. Even if you have to put a card table out in the middle of the yard it will help. You cant kill the hawks legally so the best bet is to prevent them from seeing your birds. A dog can be enough to stop a hawk from attacking. You could also set a decoy chicken where your birds are not.
Those are great ideas that can be pit to use easily for quick fixes with everyday household items..
Someone told me to wrap a rock or a big kitchen bowl in aluminum foil on sunny day.. Hawks hate reflective stuff I guess.. I would wrap just about anything, when my Mylar balloons would deflate... Until I could get a few more the next day.. Than I did my run roofing in aluminum, though the chickens hate when the pine cone fall on it eeek
I put out a scarecrow with old aluminum pie pans tied on long strings so the blew around and hit each other. Hawks hate it! My roo Hawkie is great at spotting danger,but he's really old and only has one eye,so the scarecrow helps.