Common Sandpiper
Actitis hypoleucos
The adult is 18–20 cm (7.1–7.9 in) long with a 32–35 cm (13–14 in) wingspan. It has greyish-brown upperparts, white underparts, short dark-yellowish legs and feet, and a bill with a pale base and dark tip. In winter plumage, they are duller and have more conspicuous barring on the wings, though this is still only visible at close range. Juveniles are more heavily barred above and have buff edges to the wing feathers. This species is very similar to the slightly larger spotted sandpiper (A. macularia) in non-breeding plumage.
ID text from Wikipedia, CC BY-SA 4.0
Spotted Sandpiper
Actitis macularius
Adults have short yellowish legs and an orange bill with a dark tip. The body is brown on top and white underneath with black spots. These spots vary in degree over the course of spotted sandpipers' lives, becoming especially prevalent around the breeding season. The overall health of spotted sandpipers may be suggested by the "spottiness" of an individual. Generally, females with more "spottiness" were healthier than those who did not have as many spots. The condition of males based on the amount of spots they exhibit is yet to be determined.
ID text from Wikipedia, CC BY-SA 4.0
Where you might meet both
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