Aggressive hen

[Alclark76]

I have 2 hens (both olive eggers) that are about 4 years old. A neighbor had to move and had 2 hens around a year old (one is a jersey giant, the other an Australorp )she needed re-homed, so I took them in. I have a smaller chicken tractor separate from the main coop that I kept them in for the last 5 days, next to the main coop so they could all get used to each other.
I attempted to put them together today. The jersey giant is perfectly fine, and my hens are mostly ignoring her/leaving her alone and vice versa. However, the Australorp immediately reared up and attacked both of my hens. She drew blood and refused to release her beak grip from one of my hens until I forced her down.
I've placed her back in the separate chicken tractor, but I'm at a loss of what to do. I know she isn't a roo (laying eggs daily). Any suggestions?

 

[Debbie292d]

She's not handling the move well, obviously.

Who knows what her motives were, but I'd keep her isolated away from the rest for a few days and then try it again. Hopefully by then, the other new one will be hanging out with yours. I'd make it so they can all see each other.

 

[aart]

I attempted to put them together today.

How/where did you "put them together"?

How big are the coops and runs?
Do you free range at all?


Here's some tips about.....
Integration Basics:
It's all about territory and resources(space/food/water).
Existing birds will almost always attack new ones to defend their resources.
Understanding chicken behaviors is essential to integrating new birds into your flock.

Confine new birds within sight but physically segregated from older/existing birds for several weeks, so they can see and get used to each other but not physically interact.

In adjacent runs, spread scratch grains along the dividing mesh, best if mesh is just big enough for birds to stick their head thru, so they get used to eating together.

The more space, the better. Birds will peck to establish dominance, the pecked bird needs space to get away. As long as there's no copious blood drawn and/or new bird is not trapped/pinned down and beaten unmercilessly, let them work it out. Every time you interfere or remove new birds, they'll have to start the pecking order thing all over again.

Multiple feed/water stations. Dominance issues are most often carried out over sustenance, more stations lessens the frequency of that issue.

Places for the new birds to hide 'out of line of sight'(but not a dead end trap) and/or up and away from any bully birds. Roosts, pallets or boards leaned up against walls or up on concrete blocks, old chairs tables, branches, logs, stumps out in the run can really help. Lots of diversion and places to 'hide' instead of bare wide open run.

Good ideas for hiding places:
https://www.backyardchickens.com/threads/a-cluttered-run.1323792/