Wood Sandpiper is a small slim wader, dark grey-brown above, with light flecks or spots, and a white underbody. The light breast is mottled as well. The legs are yellow-green. There is a distinct white brow line. The flight is strong, with distinctive clipped wing beats. In flight, a square white rump is revealed and there are no wing bars."
"Wood Sandpiper: Medium, long-legged sandpiper with dark gray-brown
upperparts and
breast heavily marked with white spots and notches.
Underparts are white; legs usually green, but may be yellow and lead to confusion with Lesser Yellowlegs. Underwings pale gray;
rump is white with black-barred tail."
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