Violent Chicken

[Chickemee]

Me and my sister got new chickens today and when I tried to put them in with my leghorn she turned reley violent towards them. She got a mouth full of feathers and ripped a big bald spot off one of the poor chickens. I seperated them but Im not sure when I should try putting them back together. Could this behavior be that she got teritorial after the 2 little chicks passed away? Can anyone help me?

 

[speckledhen]

First of all, read this thread about the importance of quarantining new birds:
https://www.backyardchickens.com/forum/viewtopic.php?id=12751

After you're sure the new chickens don't have anything to make yours sick, then you should put them close together where they can see each other but not actually get at each other for a few days. Then you can try to put them together again, but they will try to work out their pecking order. Your hen was just telling them they were on HER turf now.