It is evident many folks are observing hens crow. I now think many of my hens do so as well and it may serve some purpose. The utterances I have been hearing are not proper crows of a rooster but rather greatly shortened and slightly higher pitch versions performed with wing flapping. Hens doing are either off incubation duty foraging or have chicks following them about. At first I thought it was a form of stretching but it is too loud. I am beginning to think it is a method of contacting balance of flock hen normally associates with indicating her presence and location. Such behavior may help preserve a hens rank within the flock so that when she returns fighting over rank not needed. My American games and red jungle fowl hens all do this. I will have a dominique hen brood some chicks to see if she does same.