It may seem early, but the above freezing temps today feel like a sign of spring. The Goldfinches are way ahead of us, as witnessed by their incoming spring/summer feathers.
These are not the best pictures, but demonstrate how much difference 3 weeks can make in the way a bird looks.
Longer day length is sending a message to the Goldfinch brain, causing it to release hormones that stimulate new feather growth. By the time spring actually gets here these birds will look completely different, and have new colors ready for the summer nesting season.
I took this picture on January 22, and the top picture today. I'll take another in 3 more weeks to see how much change has occurred.