I noticed today that one of my Easter eggers is missing a patch of feathers on her back. What would cause this? And should I be worried and take any actions? I have never owned chickens before.
She is probably at the bottom of the pecking order, which is why the others look fine.
Feather pecking can be caused by many things but the two most common in my experience are 1) stress and 2) diet. If it is stress that is causing the others to pull out her feathers, then giving them more space and things to explore should solve the problem. If it is diet, they might not be getting enough feed or the correct nutrition. There are lots of supplements and additives that can help, or sometimes simply changing the brand of feed will work.
It really is a trial-and-error solution, I'm afraid!