I have found a total of 4 shellless eggs in the run over the last week, none that I can tell have been laid in the coop and some days I get my typical 4 eggs and other days I get 1 or none. They are free range, I leave out a bowl of oyster shells and they have access to layer pellets all day. I have a mixed flock of 6 hens that are all roughly 7 months old give or take a week. We just had our first snow and I know egg production slows when the temperatures drop. Could it just be the weather is a shock to their system since they are still developing? How do I narrow down which hen it is? How can I rule out diseases, malnutrition etc? Help Please!