Atlanta birds

I was in Atlanta over the Christmas holiday and was able to get a few pictures of birds. It was fairly cold there. High around 48 degrees during the day. The first picture is some sort of sparrow. I think it's a house sparrow. It was on a sidewalk near a restaurant. Someone must have fed it a little piece of bread. The second is of a cardinal that I saw at Zoo Atlanta. We spent a morning there taking pictures of the baby (now a year old) panda. The cardinal seemed to be trying to eat the leaves. I know these birds aren't migratory but wouldn't it be nice if they would just fly south for the winter and get some warmth?