4 day old chicks beating up day olds, why?

[BikerBabeRules]

I have 4 chicks that are 4 days old. I had a couple more hatch and when I put them in the brooder box with the others, they older chicks (one started it, a bantam at that) just downright mauled the 2 new chicks. She had them on their backs, and just was like a machine gun on them. I have never had this sort of thing happen before. There is plenty of room in the brooder, fresh pine shavings, plenty of heat. What's going on? I've since taken the new guys out and they are in their own brooder and peace has been restored.

 

[annrich]

hmmm. I don't know if I can help with that one. I have 2 weekers I tried to keep seperate from day olds yesterday after their arrival. Due to my own negligence they ended being together. Everyone is fine. They were great this morning too.
I will be interested to see what everyone else has to say. Good luck to you.

 

[Cuban Longtails]

That happened with mine and only lasted as long as it took the new arrivals to start fighting back. Now they all get along just peachy. I've no explination as to why it happens.

 

[Grass]

mine was opposite ...the new arrival was the one that was brute .....after couple hours the 2 day olds and 2 week olds got along fine

 

[pattee]

I have 11 new babies (4 days old) and the 2 bantams went after the biggest chick like crazy... they seem to want to pick on everybody!
I don't know how to handle it. Except separating them.