Systematics

Geographic Variation

P. dominica: no intraspecific variation reported. P. fulva: Variation is slight across the species’ range, but birds that breed in Siberia have shorter wings than birds that breed in w. Alaska (see Measurements, below).

Subspecies

P. dominica: no subspecies known, but note that Charadrius pectoralis Vieillot, 1823, C. virginicus Lichtenstein, 1823, C. marmoratus Wagler, 1827, and Pluvialis americanus Schlegel, 1865, are junior synonyms of P. dominica (Müller, 1776).

P. fulva: no subspecies known, but note that Charadrius xanthocheilus Wagler, 1827, C. taitensis Lesson, 1828, C. glaucopus Forster, 1844, C. orientialis Temminck and Schlegel, 1845, and C. longipes Schlegel, 1854, are junior synonyms of Pluvialis fulva (Gmelin, 1789).

Related Species

The family Charadriidae, the plovers and lapwings, is well supported and is one of the core groups in the shorebird (Charadriiformes) radiation. Within this family, the genus Pluvialis is also well defined (Bock 1958): it consists of four species worldwide, each broadly similar in shape, size, and general plumage pattern (see Distinguishing Characteristics, above), although P. squatarola (the Black-bellied Plover, or “Grey Plover” in Europe) differs from the three golden-plovers, P. dominica, P. fulva (the Pacific Golden-Plover), and P. apricaria (the Eurasian Golden-Plover) in its vestigial hind toe. The four species have been compared and contrasted in terms of downy plumages (Jehl 1968), osteology (Strauch 1978, Mickevich and Parenti 1980, Chu 1995), allozymes (Baker and Strauch 1988, Christian et al. 1992a,b), DNA-DNA hybridization (Sibley and Ahlquist 1990), and vocalizations (Miller 1996). Relationships within the Charadriidae are less clear, and it may be that Pluvialis is rather distantly related to Vanellus (lapwings) and Charadrius (shore plovers; Thomas et al. 2004, Baker et al. 2007), the two most speciose genera in the family.

Pluvialis domininca and P. fulva were long considered to be conspecific, and were treated collectively under the English name the Lesser Golden-Plover. Connors (1983) argued strongly for a split, and Connors et al. (1993) provided evidence that there exist “clear and consistent differences in breeding vocalizations and nesting habitat, and strict assortative mating in areas of sympatry in western Alaska.” Speciation of P. dominica and P. fulva probably occurred in refugia associated with Pleistocene glaciation. Larson (1957) outlined a plausible evolutionary scenario for the origins of these two taxa plus P. apricaria. Initially, the fledgling taxa were isolated during a warm interglacial within cold tundra refugia of n. Greenland–Ellesmere I. (P. apricaria) and highlands on either side of the Bering Strait (P. dominica, P. fulva). The three incipient species remained isolated during the last glacial maximum in tundra refugia of Europe–w. Russia (P. apricaria), Beringia (P. fulva), and ne. North America (P. dominica). Subsequent colonization of w. Alaska by P. fulva likely came from the Chukotsk Peninsula, with P. dominica colonizing from the opposite direction (Portenko 1973). Different “requirements of migration and winter range” that yielded selective pressures against hybrids may have driven speciation of the two North American species (Connors 1983).

Baker and Strauch (1988) reported “very low levels of within-species genetic variation” in P. dominica, which they attribute to a population bottleneck, perhaps caused by excessive hunting (see Conservation and Management: Effects of human activity, below).

Reports of possible P. fulva x P. apricaria hybrids (Pym 1982, Golley and Stoddart 1991, McCarthy 2006) perhaps more likely represent individual variation within each species rather than interbreeding.