Urban Food Garden

SEASONAL BLOG: Possible Hen Pecking Order Signs?

I have a question for fellow poultry keepers.

I recently noticed that my five Hyline hens show varying degrees of feather loss just behind their combs, ranging from about a square centimetre bald patch though to one hen with no feather loss at all. Rather than being a health issue I was wondering whether what I am seeing is simply signs of the pecking order? The hen without feather loss being the dominant one (no-one pecks her) and the hen with the most feather loss being the hen at the bottom of the pecking order (everyone pecks her). The three in-betweens with some feather loss being in the middle level of the pecking order, both pecking and being pecked to varying degrees.

While I have kept chickens for thirty odd years, I do not consider myself an expert on chickens (I am more of a veggie gardener). Can any of you more experienced chicken breeders shed light on why my hens have varying degrees of feather loss behind their combs?
Note that the hens seem healthy, they have been wormed regularly and show no signs of lice. They are also laying well for hens into their third year. But, while I have no doubt that the hen without the feather loss is the dominant hen, I have rarely seen her or any of the other hens peck another hen behind the combs.

Your thoughts please.

TOP LEFT: The hen that I think is the dominant hen, without any feather loss behind the comb.  TOP RIGHT: The hen with the most feather loss behind the comb.  BOTTOM: Hens showing varying degrees of feather loss behind their combs.