Yellow-rumped Warbler

This weekend I heard a new bird while I was sitting out on the patio. When I finally spotted it, I made note of its markings including, "This guy has a yellow butt." As it turns out, his name really fits! This bird is a Yellow-rumped Warbler.

Since I've moved to the Southwest, I've found it interesting to discover how many variations there are within a species because of interbreeding and regional differences. That makes identifying birds out here a bit tricky. Back East, most birds look and sound pretty much the same.