A Bit of a Riddle

All of the published range maps I have seen for the American Coot indicate they are year round residents of Texas, including Bexar County. However, my personal observations are that this bird leaves the area in the spring and returns to spend the winter here about mid-autumn. The San Antonio Audubon Society's Seasonal Field Checklist is consistent with my own observations.

I have no idea why the American Coots leave Bexar County or where they go during the summer, but they are beginning to return:

This set of photographs was taken along the Mission Reach of the San Antonio River near the Roosevelt Park Trailhead on Thursday, October 31, 2013.