Our chickens have had small spots on the comb, which we thought were due to pecking, but now this one is much pronounced and concentrated in one area. Could this be a disease and potentially contagious?
Looks like it is caused from pecking to me.
Is this one the bottom of the pecking order?
Some things that can cause pecking are the size of the coop/run being too small for the number of chickens, not enough places for chickens to hide from each other, providing light to continue laying in the shorted sunlight days, and the pecking order.