09 Rock Sandpiper, St. Paul Island, Alaska. 28 Jul 2012.
Aleutian Rock Sandpiper, Calidris ptilocnemis couesi. Clearly darker and somewhat smaller than the expected C. p. ptilocnemis on this island. Identified primarily by the extent of white in the third primary, but supported by other characters (see especially the BNA account for this species). Complete eBird checklist: ebird.org/ebird/view/checklist?subID=S11228856