Probably. How old are they. Someone correct me if I am wrong but I do believe they have their first big molt around 18 months. Some you will not even notice they are loosing their feathers and others will look a litte ragged until their new feathers grow back in. Or maybe they all just had a pillow fight that you don't know about.
No mites and their not pulling them out. This is going to sound stupid, but all the feathers around their bum are the one's they are losing. They are really fuzzy and their are no bear spots or mites/lice. If they lie down in the grass the fuzzies are in the grass. Maybe two to three in each spot. And it just two of the six that are loosing the fuzzy feathers. It seems not so fuzzy feathers are taking the old feathers spots.
They're probably just getting they're big girl feathers. It looks like a feather explosion in my pens right now....and there's only a few older hens that are molting right now. Most of the feathers are from the younger pullets.
I've suspected this, but now you've confirmed it!!!!! I didn't think they were moulting because they still look so darn good. I wonder where they hide that pillow and whether there are any feathers left in it!