Copilot tells me this is a female Red-winged blackbird. I'm not sure if that's accurate or not, but we see a lot of these flitting about pastures and fence lines here in rural central Texas. Their song is very beautiful, and on this occasion I really loved the way this TINY female was perching among some creek-side reed stalks in the morning light. I'd estimate this bird is about the size of a toddler's fist.