I had this problem BAD last winter and eventually found a solution. They went through bags of feed in days! I tried everything.. I hung stuff up, no effect. My boyfriend and I shot piles and piles of them with a .22 but they would just fly away and come back with hundreds more when I wasn't out there.
I moved the feed under cover, and they would get up under there and devour everything still. I moved the feed into the coops and when I'd go out there to open the nest box doors, the birds would pour out like a black waterfall, smacking me all over and pooping all over me! I was SO FED UP. They were even roosting in the coops overnight.
Finally, I made a scarecrow, put real clothes on it, jeans, a heavy jacket and an orange hunting hat. I drew a face on it. It worked!
Every once in awhile I moved it around to different areas of the runs but always in an easily viewed space ( I have coops and runs in one big, connected line.) I would watch birds stage in trees a good distance away and see the 'person' and proceed to fly away.
The only time a bird every even came close is if it came in low and never saw the scarecrow until it was right by it, they would always take off in a panic.
Sometimes the wind would blow it over and I'm honestly surprised ( and a little worried, lol ) that someone driving by never called the police over a body laying in the snow. Lmao.