we have 7 rhode island red hens.. they are over a year old. they were purchased together and raised from peeps. early this summer we have had problems with 2 beating up on one. picking and plucking out feathers. so we separated her from the rest.. she has her own area to sleep and free ranges in the yard. the others are in a coop and have a yard that we let them out of atleast once a day for a few hours to free range. they don't pick on her when they are all out together. we have tried putting her back in the coop but the same thing happens... 2 attack her and she hides her head under her wing and makes a high pitched sound. we let her out and she is ok. This hen will stand up to our jack russel/mix terrier with no problems... but she won't fight back against the hens that pick on her. our concern is for the winter.. she would be much better off in the coop with the others for warmth...Is it true that other hens will attack until they kill? would appreciate any information you have on this.