One of my birds is laying the biggest eggs I've ever seen (in my limited experience). I have a feeling it's one of my battleship sized Production Reds. Here's a pic. Next to the egg layed by my Buff Orpington. Is this normal or something I should be concerned about? They are free range supplemented with crumbles from TSC.
We have a mixed flock and not all their eggs are the same size. The largest ones and they are LARGE, are laid by our Red Sex Link girls and the smallest by the Speckled Sussex (although they are a decent size too). Everyone else (Plymouth Barred Rock, Easter Egger, Rhode Island Red, Black Australorp) fall somewhere in the middle of the other 2 breeds. I think what you're seeing is normal, Every once in a while one of the girls will lay an especially big egg that turns out to be a double yolker but then they go back to laying their 'normal' size eggs.
It just surprised me since the one who lays there usually lays a normal sized brown one and twice in a row I've gotten he big ones. What caused double yokers? I've been selling my eggs to some friends and one of them comments on how this bunch as a lot of double yokes. A couple months ago.
Here's a quote from the Common egg quality problems" article: 5. Double or multiple yolk eggs These are more common with your pullets just coming into lay. This happens when more than one yolk matures and gets released at the same time. As many as 9 yolks have been found in a single egg. You can read the entire article here (pretty interesting stuff and good for future reference): https://www.backyardchickens.com/a/common-egg-quality-problems Hope that helps!