I have 5 chickens, all laying. I usually go collect eggs around 5-6 pm after I'm done working for the day while they are still free-ranging. Sometimes, life gets in the way and I cannot get out to the coop before dark. This used to be no big deal. I would go out, make sure everyone was on the roost, and then grab the eggs from the nesting box In the last month it has happened 4 times and I've discovered that if I do not get the eggs before the girls return to the coop for the night they break the eggs open. Tonight, 4 out of 5 eggs were cracked open. I think I'm gonna put some porcelain eggs out right before they go in the coop and set up a camera to see who is doing it. Maybe unsuccessfully pecking at a porcelain egg will break the habit.