I am new to raising chickens. Our first flock is not quite a year old (hatched about early March 2016). We have 4 Buff Orpington hens, 2 RIR hens, and 1Silky rooster. Things have been great so far. We have a nice 4x8 coop/run but we also let them free range for about an hour a day. After Christmas, we went out of town for about a week and I don't think our house sitter let them out nearly as much as we did. That's when we noticed one of the Buffs was missing a patch of feathers on her back. So, we been making an effort to let them out every day in spite of the significant drop in temperatures and it's nearly sundown by the time we get home from work. Today I noticed a 2nd Buff is starting to get the same bear spot on her back. So, is this the beginning of molting or do we have a board bully? I've attached pictures below of the 1st one to loose her feathers for reference.