Hen mounting other hen?

[Jaylee52]

New chicken keeper here.

I have 8 adult hens all about 1.5 years old that I adopted from their previous owner about 2 months ago.

Today, I saw one of my Ameracauna hens (the feistiest and most assertive of all of my hens) hop on top of one of my RIRs (the one who I think is #8 of 8 in the pecking order) and basically try to mate her. She stayed on top for 3 to 5 seconds and spread her wings and seemed to hump her. I've never seen this before!

Is this a dominance behavior like when female dogs do this to other dogs?

Is this really common or is it a sign of increasing tensions in my flock?

 

[Hamiam]

Your right, sign of dominance. Very common. My head hen stopped the behavior when I got a rooster.

 

[aart]

Is this a dominance behavior ?

Is this really common or is it a sign of increasing tensions in my flock?

Yes, and it's fairly common.
Whether it will create unacceptable tensions depends on the birds involved.
There are both benevolent and tyrannical 'heads of state'...which your head hen is remains to be seen.

 

[FiddleChics]

@Jaylee52 - Even though it's an old thread - I'm so glad I found it! I just noticed the SAME thing going on with one of my pullets! I have ten, 22 week old pullets , some of which are laying, but some aren't yet, and I also have two, 1.5 year old hens, one of which is the Alpha.
The little challenges going on among the middle/lower ranking girls seems harmless, but I have seen 1 particular pullet (Twanda - a Blue Easter Egger who hasn't started laying yet), mounting the lower ranking girls on several occasions. Twanda's normally very sweet, but she's been challenging the other girls, I guess to raise herself up in the pecking order... I've seen their neck feathers flailing out as they stand up tall... eyeing each other, then they walk away. But Twanda's taken it a step further & mounting the lower ranking girls. I was alarmed because Twanda's not laying yet, and I worried she might be a rooster - so I'm VERY glad to read it's one of the ways they might try to establish dominancy - confirmed in this thread! Whew! I can not have a rooster because of town ordinance... So just glad to know this does happen!