I was wondering if anyone else had ever noticed their roosters exhibiting a kind of "head shake" maneuver, which seems to be some sort of dominance behavior? I only started noticing them doing this after introducing new "chicks" into the existing flock of adults. The chicks were brooded in the house and then added to the coop once they had feathered in completely (moved out in groups of 3 or 4 when they were between 8-10 weeks old). Since then, I have witnessed each of our two roosters making these odd movements toward the younger chickens, and was wondering what this behavior means in "chicken language". So far, I have assumed that it's either used as a warning or threat, or simply as a means of showing off, as roosters tend to do. All the chickens seem perfectly healthy, and the head shake is not accompanied by any coughing or gaping; so I feel sure it is has nothing to do with any symptom or illness... but as a form of nonverbal communication between the birds. If anyone else has noticed this behavior, I'd love to hear about it, as well as the situations that prompted it, and your interpretations of its meaning. Thanks!