Been there, done that, and it's tough. Given the time of year and where you live, I'm assuming they aren't free ranging. My first suggestion is to add a decoy owl or two that you'll need to move around every day so the hawks will think they're real. If that doesn't send the hawks on their way, get some bird tape that shines brightly in the sun. It should blind the hawks just enough to keep them from swooping in. I feel your pain! Good luck!