Yep, agree with Think Of England! Only one of my chickens does it and I never knew why until I got more and realised that this behaviour is not so that a chicken owner can conveniently pick up the chicken for a bit of a chat, but definitely meant for the lads. Most of my chickens just run like mad when the cockerels are let loose first thing in the morning, but this behaviour is sometimes displayed by the more wanton of the flock. Tut.