HELP! Week old chick is a bully

[koolfunchicks]

Hello,
I am new to chickens and have learned a ton from you folks at BYC. Here is my problem: I purchased 8 chicks from our local feed store 11 days ago: 2 BR, 2 Light Brahma, 1 GLW, 1 Maran, and 2 EE. All but the EE's were 1 week old when I acquired them and the EEs were 2 days old. All was well until day 5 when one of the EE's started aggressively pecking the others. Thinking they needed more space, we expanded the brooder and it is now 3' X 5.5' Things seemed fine until two days later when we noticed several chicks with bloody wounds. Sure enough, it was our EE Frida (who we now refer to as Frida Kruger). I treated the victims with blue wound care spray and separated the perpetrator in the brooder using a wire fence so she can see her "friends". It has been 2 days of solitary confinement. I have observed her continuing to try to peck through the hardware cloth if an innocent chick happens to lie near the fence. Do you kind folks have any suggestions for me? Do mean chicks typically grow in to mean hens? At what point do I try to reintroduce her to the flock? At what point do I give up and return her to the feed barn (If they would even take her back)? BTW the temp in the brooder seems fine based upon the chicks behavior and I added a rock for them to jump on and a small perch so I don't think it is due to boredom. Any advice is GREATLY appreciated!

 

[Chicken Egg 17]

It don't necessarily mean it will be a mean hen it could be a rooster and or just being a hen that is highest in the pecking order I would introduce her in a couple of days about two and see if she still does it please keep me updated hope this helps

 

[realsis]

It don't necessarily mean it will be a mean hen it could be a rooster and or just being a hen that is highest in the pecking order I would introduce her in a couple of days about two and see if she still does it please keep me updated hope this helps

This is what I was thinking exactly. is the bird a confirmed female? I've had cockerals which I thought were females (silkies) that just acted more aggressive than the other females. he would fly at them peckd and act like he wanted to spur them!running at them. Then this one cockeral in particular started to get mean with me too!! He would peck my hand when I fed. As he got older I learned he wasn't a she !!

 

[koolfunchicks]

Thanks for the suggestions. To answer your question: is she a confirmed female? She came from a hatchery that claims a 90% sexing rate. Since she is only 11 days old, I don't know if one can confirm that she actually is a pullet. If there is a way to tell at this age, I am all ears. After two days of separation I tried introducing her again and within the first minute she/he aggressively pecked at two different hens. She is back in solitary confinement for the night as I don't want to subject the other seven chicks her aggressive behavior. I did find someone willing to raise her so I might give her away. It has been quite a dilemma. The other seven seem to get along just fine.