Jan 15 - This is one of the Black Capped Chickadees that frequent my feeders.
Today was very cold. I think our high today was 17 degrees F. As I watched this little guy, I noticed that he would periodically tuck one of his legs up into his feathers and he was also puffing his feathers out quite a bit. I'm assuming that this is behavior that helps keep them warmer. I know there are lots of blood vessels in their legs & feet and that would be where they'd lose most of their body heat. So, when he's resting, he must try & conserve some of that heat in this manner.