In the summer the male is a bright yellow with black wings, tail and forehead. The female is a bit duller in color. In the winter they can be a yellowish brow or gray. They can look different in different regions across the US too, I have seen them in the winter months up in New England and they looked a bit brownish. When I first saw them down in the Carolinas in the winter I had to ask someone just what bird I was seeing! They actually had a greenish coloring to them in the winter, I thought that I had seen a new lifer! They mostly eat seeds and if you want to attract them to your feeders put out some thistle seeds, they love it!