Bald spots and "sitting"

[Forest Lady]

Hello. I am new to chickens. I adopted my son and daughter in law's small flock (six hens) when they moved into a home with a HOA.

What brought me here is that a couple of them, one of the Buff and one of the Partridge each have a bald spot on their backs. I thought it could be moulting but it has been several months and the spot seems to be about the same. Though on the Buff it looks like it may be growing back in. I wondered also if it could be mites, but it hasn't spread.

Also, the last couple of days the Ameraucana has been "sitting" a lot, even to eat. She CAN stand and walk. But I noticed she was "sitting" to eat, she has never done this before. (photo attached) Her eyes and "expression" seem fine. She's alert. And when she does stand and walk, it seems without effort. The last week or two has been very hot. We were in the 100s, which for this area is extreme. I made sure they had plenty of water and they do have shade. But the heat did seem to affect her more than the others. Could this cause her to want to "sit" more? Is this normal? Should I be worried?

Otherwise, they are laying well and seem happy and healthy.

 

[Wyorp Rock]

The one that is sitting may benefit from some extra vitamins. Provide her with some B2 (Riboflavin). Check her hocks to make sure there is no discoloration or swelling.

The feather loss on the back looks like rooster treading.