First, if broody's have overrun your nest boxes you can check out how we beat that crunch for free right here: Free nest boxes. Next, you're probably going to want to sell some of those chicks. If you've ever tried to take a hen away from her babies you know what a huge fit a little bird can pitch! Squawking, hollering, pacing, frantically searching and just generally breaking my heart! awwww. Sometimes it doesn't even end there though. Take her chicks away too soon after hatch and they often go right back in the nest box and try to hatch chicks again. It's a hormonal thing and if they don't raise the chicks long enough...the hormones just don't have time to 'reset' and they still have that need for babies. This can be a vicious cycle.
Unfortunately we run things around here like a business and I can't always do what the hen wants. I came up with a simple solution. Never EVER take her last baby! I will sell her chicks off one by one (or sometimes faster) but never EVER sell that last baby! Eventually it outgrows her and when she's ignoring it, I move it down to the grow out pen. Then it can sell. If for some reason I want to keep a certain color or breed, I will either give her an egg or 2 to hatch or slip the chick under her on hatch day. That way there's no worries at all, she's already raising a keeper. I often give my Silkie hens some Guinea keets to hatch, they just grow up so much tamer....and since that baby is destined to live here I don't have to worry about taking her last baby.
Sometimes they do still get upset when I take a few babies, but they calm down a whole lot faster when they have some kids left to watch over. It stresses the hen less and stresses me less knowing she'll calm down quickly.