Just expanded the hen's dog-kennel chain linked enclosure from 10x10 to 10x20. Sooo, it was time to take my 7 RIR girls (they're over one year old now) from the "stall in the barn coop" to the outside world, again. After chasing them all of the 12 x 16 stall, I get the last hen into the 'kennel' and I see my two toughest hens having a roosterish fight, heads raised up high, beaks down, neck feathers out, and circling each other before the "attack.," JUST LIKE..you know! It only lasted a few minutes, #2 submitted, and then all was well. Anybody have any clue why this happend? They seemed to be pretty calm in the stall all winter.