Back at the Jefferson Parkway Wetlands here in Northfield, on 27 October, I photographed this American Coot. Standing on one foot, definitely stretching or practicing for a synchronized swimming performance. Brisbin and Mowbray (2002) simply list stretching among “comfort movements” noted in captive coots.
I am surprised that primary feathers appear to be absent. The authors cited above report that coots lose primaries, secondaries, and all wing coverts almost simultaneously. The result is that coots are probably flightless for about four weeks. Primary feathers take a few more days to be replaced than the secondaries. This difference, however, probably does not explain the lack of primaries in this bird since the secondaries are long.