By Adam Weaver, Wild Oysters Intern

Peeps! Aside from the proverbial reference to one’s friends, what may come to mind for many is the delicious marshmallow candy that fills Easter baskets every year. However, there are other peeps out there that are even more adorable, albeit less tasty. These adorable peeps are formally known as the five smallest North American Sandpipers. From smallest to largest, the peep family includes Least, Semipalmated, Western, White-rumped, and Baird’s Sandpipers. Identifying between these Sandpipers can prove exceptionally difficult and is reserved for the keen-eyed, committed birder. Although quite similar in general appearance, there are differences in size, territory, and mannerisms that make discernment within the peep family possible. Let’s learn how to tell these little birds apart!
The Least Sandpiper is noticeably smaller than other peeps and the easiest to identify. No larger than a sparrow, the Least is usually spread out among muddy edges of estuaries, near vegetation that can be used as cover. Leasts keep their chests close to the ground and delicately pick right in front of their feet for crustaceans, insects, larvae, and snails. They have rounded heads and a short bill that tapers to a fine point. Their large eyes dominate the face, giving the bird a wide eyed appearance. The leg bones and joints are noticeably thinner than those of other peeps. In flight, they resemble bats and have short, rounded wings that are noticeably kinked back at the wrist. In a mixed flock, Leasts will have noticeably more narrow wings than other peeps. The Least Sandpiper breeds in Northern Canada and Alaska, migrating over most of the United States for winter to settle along Southern/Western U.S. coasts, Mexico, and as far south as northern South America.

Standard peeps, the Semipalmated and Western Sandpipers, are the most common peeps in North America and both species form large flocks on tidal mudflats. Unlike the Least Sandpiper, the standard peeps keep their breasts upright and reach further forward with their bills while feeding. The difference can be likened to a person eating in a crouched position (Leasts) and eating by bending over at the waist (standard). The standard peeps are larger and have visibly thicker legs. The differences between the Semipalmated and Western Sandpiper, though, are quite subtle. Semipalmated Sandpipers are the dominant peep species throughout eastern North America, except in late fall/winter, when they migrate to the West Indies and northern South America. Western Sandpipers dominate the western side of the continent. Western and Least Sandpipers are the only peeps likely to be seen in North America during the winter. However, Western and Semipalmated Sandpipers’ migratory paths convene over a large area of the central United States and are frequently cited together. Physically, Semipalmated peeps tend to have a more robust breast and belly. This gives them a rounded appearance and a proportionally smaller head. Inversely, Western peeps’ necks look long and more slender, and they sport a head that looks too large for their body.

White-rump and Baird’s Sandpipers are the largest in the peep family and are referred to as the “long-winged peeps”. They have noticeably longer primary tips that cross over one another. These long wings enable them to encompass a larger territory than other peeps, with annual round trips between the high Arctic and the southern end of South America. Both are commonly seen stopping along the Great Plains during migration. However, White-rumped sandpipers migrate in a more elliptical fashion, moving through the Great Plains on their way North and taking off from the Canadian Maritimes and through the New England region on their way South. On the other hand, Baird’s are the primary migrant through the middle of the continent and are rarely observed on either coast. Baird’s can be observed taking very small steps, bobbing their heads while walking and eating more dramatically than other peeps. Like Leasts, Baird’s have proportionally smaller heads and shorter bills, as well as large eyes that give them a permanently surprised look. In contrast, White-rumped sandpipers have a heavier bill, sporting a slightly larger headed and bulkier appearance, with a more upright stance. They also tend to tilt sharply forward while feeding and do so in a quick and aggressive manner, similar to the Semipalmated Sandpiper. Although oversimplified, it helps to think of the White-rumped Sandpiper as a larger equivalent of the Semipalmated Sandpiper and likewise for Baird’s and Western Sandpipers.
Think you can tell the difference between all these peeps? Check out the photo below, and exercise your knowledge of the peep family!

Image sources:
http://kevinkarlsonphotography.com/gallery/d/4504-2/Least+Sandpiper_+breeding_+AK_+May.jpg
Sources
http://www.naturebob.com/sites/default/files/Identification%20of%20North%20American%20Peeps.pdf
https://www.allaboutbirds.org/guide/Least_Sandpiper/id
http://www.audubon.org/field-guide/bird/least-sandpiper
http://www.audubon.org/field-guide/bird/western-sandpiper
http://www.audubon.org/field-guide/bird/semipalmated-sandpiper
http://www.audubon.org/field-guide/bird/bairds-sandpiper
http://www.audubon.org/field-guide/bird/white-rumped-sandpiper