Runt getting pecked

[WRFarmer]

I am new to chickens. Finished the coop and run last saturday afternoon and adopted 2 Bard Rocks and 3 Rode Island Reds Saturday night from friends who wanted out of the chicken life. When we picked up the hens, one of the RIRs had bald spots on each shoulder and on the underside of the neck. She is the runt of the group and I think she is being pecked by one or more of the bigger hens. Is there a way to stop this? She looks like heck and we are having a late cold streak here in Colorado so I'm sure she is not staying as warm as the others due to the lack of feathers on her neck and shoulders.
And speaking of the cold, how cold does it need to be to require a heat source in the coop at night? I put a shop light with a 75 watt bulb in it this evening because the temp is supposed to get down to 15 tonight. Is this sufficient or do I need to buy a "coop heater".

 

[rockiemtchix]

You might try separating her along w 1 or 2 of her allies. I'm having the same issue w 4 easter eggers and 3 New pullets I recently brought into the coop, 1 of which is a bantam. The sweet pet bantam gets picked on, and I'll not have it & neither will the 2 hens she arrived with. Luckily, her allies, 2 australorp, constantly protect her and even give the EEs a good peck when they get too close or naughty. I separate the EEs from the Banty & australorps during feeding and other times during the day...just for a break. Especially now during this cold-snap in CO...they are cooped up too long. Once weather warms again and they can begin free-ranging, I think the "picking-on" will lessen. If not, it's just the cruel reality of survival of the fittest, I guess, oh and you'll have to consider permanent separation if the others continue misbehaving.