Systematics

Also known as Thick-billed Plover.

Generally 3 subspecies recognized (Ridgway 1919, Hellmayr and Conover 1948, Blake 1977). Geographic differences noted in coloration of upperparts, facial and head pattern, and width of breast-band; no differences in size noted (except perhaps middle-toe length).

C. w. wilsonia Ord 1814: Breeds along Atlantic, Gulf, and Caribbean coasts of North and Middle America south to Belize, Bahamas, Greater Antilles, and Leeward Is. (absent in Lesser Antilles south of Dominica); winters along Gulf Coast southward to n. and e. South America (e.g., Bahia, Brazil). Recorded casually to interior of e. North America (see Distribution, above). Dark loral stripe narrow, not extending to anterior portion of forehead or malar region; white frontal band across forehead relatively broad; white line above auriculars (rear supercilium) generally distinct; middle toe 18–20 mm (Ridgway 1919). West Indian individuals formerly recognized as “ rufinucha,” but no consistent difference exists (Ridgway 1919, Hellmayr and Conover 1948).

C. w. cinnamonius (Ridgway, 1919): Resident in s. Caribbean from ne. Colombia, islands off Venezuela (Netherlands Antilles; Islas Margarita, La Orchila, Los Roques, and Las Aves; and Trinidad) to Lesser Antilles (the Grenadines [Mustique I.], and Grenada). Similar to nominate wilsonia, but females differ in having rusty suffusion (cinnamon or sayal brown) on crown, sides of head, and chest-band; black areas of males frequently have mixture of rufous. This Caribbean race was sometimes incorrectly referred to as “ rufinucha ” in early literature (corrected by Ridgway 1919; see above).

C. w. beldingi (Ridgway, 1919): Breeds along Pacific Coast from central Baja California south to Panama and in South America to nw. Peru; winters over much of breeding range and south to central Peru. Report of breeding east of Andes in Ecuador (cited in Blake 1977) is almost certainly in error (likely Collared Plover). Casual north of breeding range along Pacific Coast to central California (1 breeding record from Salton Sea). Loral stripe broad, extending broadly beneath eye and into anterior portion of forehead and malar region (this region and lores producing broader mask than nominate wilsonia); white frontal band relatively narrow; white above auriculars (rear supercilium) indistinct or absent; upperparts on average darker, breast band broader (with some overlap), and more extensive cinnamon coloration on crown (males) and breast band (females) than nominate wilsonia; middle toe 17.5–18 mm (Ridgway 1919). Although Monroe (1968) synonymized this race under nominate wilsonia, most authors maintain beldingi as valid.

Within genus Charadrius, Wilson’s Plover is part of ringed-plover complex, a monophyletic assemblage also including Common Ringed (C. hiaticula), Semipalmated, Piping, Long-billed (C. placidus), and Little Ringed (C. dubius) plovers, as well as Killdeer (Bock 1958, Joseph et al. 1999; phylogenetic analysis of mitochondrial DNA [M. Peck pers. comm.]). Although close association with ringed plovers is well supported, Wilson’s Plover was thought distinct enough in the past to have been placed in separate genus, Pagolla (Am. Ornithol. Union 1931).