What is this? Pic included.

[holyhart]

My new polish chick (she is about 6 weeks) seems fine in every way. Except this weird bubble on her back, kind of inbetween her shoulder blade. I've lightly pressed on it and it feels like it is filled with air like a bubble would be. Of course I did not try to pop it. What is this? What should I do about this or should I not do anything?

 

[holyhart]

Any ideas? What's wrong with her?

 

[fkreye]

If you google "bubbles under the skin on chickens", there are lots of other threads in BYC that show up and talk about it. Not sure if they are the same thing or not but one of them might help! Good luck!