Least Sandpiper
This small sandpiper has possibly yellow legs with wingtips not extending past tail.
BD: Adult Least in winter plumage. Note the overall relatively dark gray look of the bird, the relatively wide black central feather markings, the leg color, the bill shape, and the very long toes. The long toes of Least allow it to forage in a different posture, more crouched with little down angle to the back, compared with most other sandpipers with relatively short bills. Can sort of tell the leg color is not black.