Bored or Cannibalistic?

I'm referring to Winifred, our Easter Egger chicken.  On Sunday and Monday of this past week, I went out to get the chicken eggs and I found them broken.  Both times I found the chicken egg on the floor of the big coop.  The first day I thought it was just a fluke.  We have had eggs that had a hairline crack in them in the past but these were different.  This was the kind of cracked you would expect if a chicken was pecking at it with her beak.  See below.  On Tuesday, when it happened to one of the duck eggs I knew I had a problem on my hands.

Cracked duck egg.  

So Tuesday morning after finding the cracked duck egg, I went back and closed the big coop door so that any chicken wanting to lay an egg at this point would have to do so in the smaller coop that has nests in it.  I figured it would be harder for a chicken to 'play' with an egg that was in an actual nest plus I would be better able to keep an eye on the situation.  The chickens however thwarted me.  They didn't lay any eggs all day.  

Locked coop door.  

So this morning I got up early and went out to collect the duck eggs before any of the chickens could crack them.  I was successful.  The ducks were up and had laid their eggs but the chickens were still sleeping.  Then when the chickens got off their roasts and went outside I locked them out of the big coop and kept an eye on the small coop.  Finally around 11 am Marion went into the small coop to lay an egg.  I went back about 30 minutes later and shooed her off the nest and took the egg before Winifred could even know it was there.  Mike says I am obsessing but I say it was worth it.  This is the first chicken egg I have gotten to keep in over a week.  

I really don't want to have to keep watch over these chickens all the time.  I have to stop Winifred from being an egg-eating chicken.  According to the Internet, she either needs to be rehabilitated or I need to distract her because she is doing all this out of boredom.  The Internet suggests decoy eggs in the theory that pecking at an 'unyielding egg' would be so frustrating the chicken would give up.  I think I will try the distraction technique first.  I hope it works.  

Mike discovered this 'boredom buster.'  When he weed whips around the chicken coop he directs the
grass into the coop.  

The chickens and ducks run to investigate and scratch through the grass looking for bugs.  

I bought this 'Happy Hens Treat Holder'.  I hang it on a hook and fill it with mealworm and sunflower treats.
The chickens have to peck at it to get the treats out.  But as it swings when they peck at it, they really
have to apply themselves to get the treats.