Adult, breeding common sandpipers are brownish-gray on their heads, napes and breast, which are all faintly streaked with dark brown. Their bellies and undertail coverts are unmarked white. Backs, wings and tails are overall darker brown, mottled with shades of tan and very dark brown. In addition, they often have a white ring around the eyes. Like many migrating birds, common sandpipers molt after the breeding season into their winter plumage. Winter plumage is a more drab version of the breeding plumage, and the streaking in particular fades or disappears completely. The young have white speckles also on the upper part. Juveniles look very similar to wintering adults, but have significantly more buff incorporated into their mottled upperparts. This species can be distinguished from the spotted sandpiper due to their longer tail feathers and darker legs. They are approximately 8 grams at hatching and their mass increases to about 40 grams when able to fly. In addition they grow to be about 20 cm long with bills measuring 21 mm in length. Their wingspan adult wingspan reaches 35 cm. This species displays no sexual dimorphism in plumage, but females tend to be a little larger than males. (Chandler, 2009; Holland and Yalden, 1991)

 

Other Physical Features: Endothermic; Homoiothermic; Bilateral symmetry

Sexual Dimorphism: Sexes alike; Female larger