Semi-palmated or Least Sandpiper- too close to call
I had originally called this a juvenile Semi-palmated Sandpiper.
Others brought to my attention that it was too rufous for anything but a Least.
So I called upon a real expert and the decision is"too close to call"
The bill is thin enough for a Least and the rufous mantle would indicate Least, but some individual Semi's could be that dark.
The legs are darkish, but that could be lighting.
The primary projection past the tertials would lean toward a Semi.
Mann Lake, Nez Perce county, Idaho, USA