I recently added 5 new hens to my flock, (RIR, Austraulorp, 2 BR, and 1 white hen that I don't know the breed). One of them lays a white egg, the white hen? Someone is eating the white eggs. I think the white eggs are the only ones they eat. I haven't found any brown shells laying around and this morning the white egg had been laid and pecked open in the nesting box. I work full time and don't have time to watch and see who is the culprit is. I give them oyster shell. Do they think the white egg is oyster shell? I haven't had this problem before. I hung curtains over the nesting boxes and thought that was helping until this morning. Any suggestions?