About Charadrius semipalmatus Bonaparte, 1825
This bird species, Charadrius semipalmatus Bonaparte, 1825, has an average weight of 47.4 g (1.7 oz) for males and 46.1 g (1.6 oz) for females. Overall body mass ranges from 37.6 to 54.7 g (1.3 to 1.9 oz), total body length measures 17–19 cm (6.7–7.5 in), and average wing length is 12–13 cm (4.7–5.1 in). Adult individuals have grey-brown backs and wings, a white belly, and a white breast marked with a single black neckband. They have a brown cap, a white forehead, a black mask surrounding the eyes, and a short orange-and-black bill. The breeding habitat of this species is open ground on beaches or flats across northern Canada and Alaska. They nest on the ground in open areas with little to no plant growth. Charadrius semipalmatus is migratory, and winters in coastal areas of the southern United States, the Caribbean, and most of South America. It is an extremely rare vagrant to western Europe, and individuals have been recorded in Tierra del Fuego and the Isles of Scilly. Its true population status may be obscured because the species is hard to distinguish from the very similar Eurasian ringed plover; Charadrius semipalmatus was formerly classified as a subspecies of the Eurasian ringed plover.
