We had 12 chicks hatch last week. We have always left the chicks with their mothers while growing unless we sold or gave any of them away. Other than predators or sickness killing them we have never had any problems with the other chickens bothering the chicks. The only thing I do is keep the broody hens in a seperate pen while they are sitting on their eggs and for a month or two after the chicks hatch. This afternoon I went out after work to turn the chickens out and my one year old RIR rooster ran over to the other coop and proceeded to start killing the newborn chicks. He has never been violent and is actually a really good rooster. I can't figure out why he did this. When we had chicks hatch over the past couple of months he ignored them but now he seems really ticked off. I closed the chicks in a cage where he couldn't get to them and he went nuts trying to get to them, even running into the fencing a few times. Has anyone had this problem before? We usually cull out the Roosters to use as food and keep a few hens for eggs and fryers when they quit laying. He is usually a good rooster, I don't want to get rid of him or make dinner out of him but if this is going to become something he will continue to do I may not have any choice. Any advice would be greatly appreciated. Oh and he is the Father of the chicks if that makes any difference. He didn't eat any of them he just jumped on them and pecked them to death. It took me a few minutes of fighting with him to get him out of their coop and he has been acting really strange since then.