Personally, I would approach it in a completely backward way. I would tell and show them what the problem is... that the girls are fighting their way into your run and stealing your feed. Also let them know they are losing a few eggs.
Ask them if there is anything they can think of that...
I'm going to poke a hole in your crawfish theory. I just opened up a HB egg and it has orange rings! Other than veggie scaps I don't toss much to my ladies, I haven't given them any seafood.
I just cracked a few eggs onto the skillet that came out looking soft boiled already!
In our effort to divide chores more fairly, my husband is supposed to collect eggs in the morning. He often forgets and I end up collecting a few days at a time, could they be cooking in the coop, or is...
Are your chickens still ok? It would give me some hope. Mine got into a spilled packet of green bean seeds I was going to plant today. I think I caught them before too many were devoured, but I cannot find any information on symptoms or possible treatment beside one website that said dry...