Chipping Sparrow

The most mysterious thing about the chipping sparrow - to me - is that the Cornell site shows on their range map that they breed all over the US, basically, but do not winter over anywhere in the US except in the south part of Florida/Texas/California. What's weird about that is that they are ABSOLUTELY here in Central Virginia year round. When I first started taking pictures of birds back at least 10 years ago, I documented one every single month of the year on Chapel Spring Lane when we were taking our morning walks. You'd think the experts at Cornell would have figured that out by now.