It was about -15 F. when I spent some time watching birds at our feeders and in nearby trees this morning. Our coldest days tend to be cloud-free, so the light was good. Since I take many of my feeder photos through my living room window, I do some color correcting afterward to take away the dullness that the window and its glare can impart.
I love female cardinals. This one's red eyebrow is illuminated, matching her beautiful red bill. She's accompanied at the feeder by a goldfinch and, barely visible, a house finch.
This female white-breasted nuthatch caught my eye because, unusually, she was head-up on the trunk of our big maple tree, rather than upside down as one usually sees nuthatches. She's well-fluffed for maximum insulation from the cold.
This male house finch is also doing a puffball imitation to keep warm.
And this bright-eyed chickadee sat in the same position for quite a while. Was he or she miserable in the cold, or doing just fine? Our northern birds seem to handle the cold remarkably well, Here is a good overview from the Cornell Lab of Ornithology of some of the ways birds cope with severe cold, which include not only fluffing up those down feathers but eating as much as possible and sheltering from the wind.