I followed that with a walk around the local park. There were no redpolls this time, unfortunately; those birds seem to appear and disappear quickly around here. I did see a lot of sparrows, including a couple of American Tree Sparrows, which I had not seen at that location so far this year. There were more Fish Crows; in fact the Fish Crows outnumbered the American Crows yesterday. A few hundred blackbirds were spread over several flocks. Somewhat surprisingly, Brown-headed Cowbirds outnumbered the others, but Red-winged Blackbirds and Common Grackles both were well represented. Other returning birds included Killdeer, which has been mostly absent this winter. This week the local gull population has been shifting. For most of the winter, Herring Gulls were in the majority by far, with small numbers of Ring-billed Gulls and Great Black-backed Gulls. This week, Ring-billed Gulls have had a clear majority. Yesterday they outnumbered Herring Gulls about 5:1.
Bird Banding Laboratory. It will probably take a few weeks before I get a response, but I will post it here when I do.