“Peeps” is a term used by birders to describe several species of the genus Calidris that are similar in appearance. These small shorebirds all have short legs and similar plumage and feed in mud flats in search of the same food. In North America, the five species of peeps include Baird’s, Least, Semipalmated, Western, and White-rumped sandpipers. Sometimes the Sanderling is added to the list.

Least and Semipalmated Sandpipers are the most common in Ottawa and are sparrow-sized birds. Least Sandpipers are browner, have yellow legs, and a finer, drooping bill. Semipalmated Sandpipers have blunt, straight bills and dark legs. White-rumped Sandpipers are slightly larger with a medium-sized bill and have a unique reddish or brownish base on the lower mandible. Baird's Sandpipers are also slightly larger, and have much longer wings which project well beyond the tip of the tail.