This redwing blackbird was singing its heart out at Delta Ponds. Must be that time of year when they are wooing. Try this to hear the song of the redwing blackbird (I hope it works) - http://www.birdjam.com/birdsong.php?id=25

If you want to see some interesting facts about the redwing blackbird, the Cornell Lab of Ornithology All About Birds is very informative - http://www.allaboutbirds.org/guide/red-winged_blackbird/lifehistory