They are not necessarily roos. My girls do this as well. They will run towards one another and puff up their neck feathers for a stare down. Usually one will back down, but if not, the braver one give the other a swift pecking. Sounds like they are establishing a pecking order. My silkies seem a lot less likely to fight like this than my other breeds. My hen Lorraine goes to take a peck at one of the other newer girls, and she sometimes misses
Poor thing has too much fluff to see properly!
