Eating eggs or malformed?

[jkg]

We added a new group of hens to our previous group. We are finding an egg almost every time broken up in the nest box. How do you tell if one of them is breaking the eggs intentionally to eat the contents vs if one of them is laying eggs with weak or malformed shells that are breaking naturally? What are the tell-tale signs of each behavior since we're not in the nest box to see how its happening? We've got a bunch of changes going on - a new group added to the previous flock, a number youngsters just getting to laying age, the older ones coming off a molt, plus the whole flock recently through avian pox. We're struggling to get back up to our previous egg production (used to be 6-7 per day from 8 birds, now is 3-4 per day from 9 birds). Hoping one of the new ones isn't an egg eater...

 

[canada-goose]

Are the eggs empty? If the yolk and white are missing, someone is probably eating them. Check for yellow smears on the chickens' faces. Giving them free-choice oyster shell would be a good idea too.