I have a hen, well i think she is a hen. She has been seen chasing other hens around and I have seen other hens chasing her back. This evening I witnessed her grab the neck feathers on one of my other hens and mount her like my rooster does when he is breeding a hen. During this one of my other hens a Dominique came over and pecked the hen in question on the back to make her get off of the other hen. I will include 4 pictures I took of the hen in question to see if you think she might be a roo or if this is some kind of dominance activity? I can't remember her breed exactly but I think she is a Wyandotte Cochin cross. I can't recall seeing my rooster mount her before and I know they do not fight each other. Also I do not know if she lays eggs as I have 14 total birds and just usually find a pile of eggs in one or two of my nesting boxes.
Thanks for your help/advice in advance.