Systematics

No significant plumage, morphological, or genetic differences have been found between Atlantic and prairie subspecies, although slight clinal differences may exist (Wilcox 1959, Haig and Oring 1988a: Table 2, Appendix 2, Haig et al. in press). In many prairie males (Piping Plovers breeding west of the Great Lakes), a black “moustache” extends from base of bill to sand-colored plumage of upper cheek (SMH). A single black band extends partially or fully (depending on individual, sex, age, and, possibly, location) across upper breast and around back. In flight, a bright white rump is exposed. Males are brighter (i.e. darker, more complete breast band, more bright orange on bill, more pronounced white eye-line, and in some birds presence of moustache) than females, and inland breeding birds tend to be brighter than Atlantic birds (Fig. 2).

Opinion has fluctuated over recognition of Atlantic and inland subspecies designation (C. melodus melodus and C. m. circumcinctus, respectively, AOU 1957). Breast-band patterns and geographic distributions were proposed as evidence for the subspecies (Moser 1942, AOU 1945) but significance of the patterns was later refuted (Wilcox 1959). Early allozyme information data did not support the presence of two distinct subspecies (Haig and Oring 1988a). However, recent mitochondrial DNA analyses suggest subspecific differentiation, with Great Lakes birds aligning more closely with Prairie birds than Atlantic birds (SMH). Further, dispersal information from color band resightings does not suggest mixing between subspecies on the breeding grounds (Haig and Oring 1988b).