Kiwanian Harry Cross--who brought friends out to see the spectacle--explained that the swarm is called a "murmuration." Though that term turns up some astonishing YouTube videos, the explanation of the phenomenon turns out to be pretty prosaic. The starlings are "just kind of exercising" before their night's rest, says U-M bird expert Janet Hinshaw, who says she's seen the starlings roosting in the big tree in front of Zingerman's Roadhouse.
In January, the flock was no longer wheeling over Winewood, but they hadn't gone far. In mid-month, they'd moved a block south, to Liberty and Maple.
[Originally published in February, 2013.]