Rooster and Young Pullets Behavior

[Rachealx4]

This is Colonel. He is my head guy. His current crew are 6 BO pullets and my other rooster,Popeye. They all are around 12 weeks and have been raised together.
So the pecking order drama is over for the most part.
This is my flock of 3 BSL, 3 BR and 3 SLW. These girls are about a month younger and completely separated from my BO flock for the time being. As you can see Colonel is in the coop with them. My boss hen will go in too but not as much as this guy.
This morning I saw this... It was a total stare down by both. Is this just normal chicken checking you out behavior or a sign of trouble when the younger ones are big enough to merge with the flock? The younger flock has been in there for about a week or so. It's not like they are brand new.
Thanks!

 

[TheTwoRoos]

This is him letting the younger girls know he rules the roost.All chickens fight,escpecially when first introduced.The fightignshouldnt be too bad.Just watch them when you put them together.

 

[Jcbreeders]

i have question? I have some young chickens and the odd behavior they are displaying is that they are huddling together and on top of each other and we have already lost two we think to this behavior. does anybody know what could be causing this?

 

[RWise]

How old are they? What are the temps? Do they sound happy or are they calling Momma? Maybe they are cold,,,huddling is a way for them to keep warm.

 

[Jcbreeders]

they are about they are between 3 to 4 months and the temps are in the 70's and above

 

[Rachealx4]

they are about they are between 3 to 4 months and the temps are in the 70's and above

Both of my flocks will pile on each other when they are scared and feel like they can't get away, especially when they were younger.
What is going on when they do this? My younger ones will do it when I go into their pen in the coop. I take as little space as possible while I'm doing whatever it is I'm doing and don't chase them. It has helped but they will still do it.
My flocks are around the same age as yours.