It took us months (and video cameras) to figure out which hen was eating not only her own egg, but eggs from other hens, plus wrecking uneaten eggs covered with yolk and white from the ones that were eaten. My husband finally caught the suspect in the act. She was promptly culled and slowly stewed into two delicious meals. Our egg eater was at the very bottom of the pecking order, and I think this is why she did it--to get "even" in her little chicken brain. We feel a good brand of layer feed and supplement with oyster shell calcium, so she was not deficient (definitely not after she started eating all of those eggs--she did it for several months before we caught her). We installed new rollaway nest boxes, but that only worked when the hens used those boxes. Sometimes they laid on the henhouse floor, or on the floor of the coop in a nice nest of straw. The latter place is where hubby caught her in the act. She was just too hard core. Culling her stopped the problem completely, BTW. I hope you don't have to resort to that, but when you think about all the feed you waste on those lost eggs (both the ones eaten, and the others that you can't sell because they have been coated in yolk/albumen), it's a lot of money. We figured she was costing us $150 a year in lost egg sales. (We only sell to people in the neighborhood and hubby's coworkers, and we don't sell washed eggs. We do it the European way! Naturally clean eggs are sold, heavily soiled ones we keep, wash, and eat ourselves.)