Hi. A family friend had these chicks show up in their yard and they lived in the tree next to the house for a couple of weeks. we took them since we have chickens. they were separated from the others for 5 weeks. although they're still smaller than the others, i put them in the coop with the others today. a couple of our hens (delaware and a rhode island red) picked on them a little, nothing bad. then these two went after our older australorp. i've never seen anything like it. they were attacking to kill. no amount of shouting stopped them and i had to physically separate them. I'm guessing the one in front is a rooster(tail feathers, size relative to the other, and it was the primary attacker). the other is a little smaller, and doesn't have the orangish feathers or crest the one in the foreground does. they are smaller than our other chickens. they aren't australorps. does anyone know what these chickens are? and is there anything to do about this hyper-aggressive behaviour? thank you.