There was a small active flock of 15 or so calidris at the Boat Hole on the southwest side of the Gurnet portion of Duxbury Beach. Most were Least Sandpipers and at least one was a Semipalmated (last photo in series) but there were a couple of headscratchers too. The pictures are of poor quality but there is enough to puzzle over.

The bird on the left has dark legs unlike a Least, and the head and throat markings look dark without the chin white I think of with a Semipalmated. The bill looks ok for Semi. No white rump on flight. The wingtips are not particularly elongated. A dark legged Least? An oddly marked Semipalmated? - next photo is same pair