Can anyone give me the most likely guess for the following sighting? I live
in the upper Methow Valley, above the Chewuch River. Yesterday a large
shorebird flew overhead on two occasions. It was at least the size of a
willet, although I think that both its body and bill size were larger than a
willet's. Since I did not have binoculars with me, the only field mark I
have to go on is that its wings, viewed from underneath, were distinctly
two-tone--half dark, half light. It made a loud, distinct and continuous
call, which was what drew my attention to it each time. It moved its wings
in what seemed to me a peculiar, circular swimming motion. Based on these
clues and range, what would be the best guess for this bird? Thanks very
much.

Birch Berman