Ours did the same thing. Just "peck" them back. Take your index finger and poke them on the back part of the head. You have to let those ladies know it is not ok to peck you. They peck to show who is the boss. We have one girl who has to be reminded at least once a week that she is not the boss. She does not lay eggs btw. She can be very persistant at trying to peck us. When she doesn't take the initial head peck as a clue, she gets pinned down on the ground for about 20 seconds, then she decides we win. lol Also, when we sit outside at the dinner table, some of the girls will peck my mother-in-laws legs, but none of ours. They must see her as a new flock mate. lol