Out to get the paper this morning I heard a chickadee singing its fee-bee song. Two notes, first higher than the second. It's one of about 15 different vocalizations this bird can make. It tends to be heard most often in spring and early summer, most often sung by males. It's a territorial song, advertising to females, alerting other males to stay away. I've always regarded this song as the first sign of spring. It's a litte early to look at it that way, but given our weak excuse for winter, why not?