ARTICLES ON HAWAIIAN BIRDS AND BIRDWATCHING AND OTHER PACIFIC WILDLIFE

The Pacific Golden Plover (Pluvialis fulva)

The Pacific Golden Plover (Pluvialis fulva), known as the Kolea in Hawaiian, is the most common of Hawai'i's migrant shorebirds, with birds wintering in large numbers in almost all types of available habitat, from coastal pastures and wetlands, to parks and gardens, to the high altitude slopes of Haleakala Crater. Most adult birds return from their Arctic nesting grounds in late July and August, with juveniles following in late September. Most birds then leave by early May, although a few remain throughout the summer. Those birds that decide to stay in Hawai'i throughout the summer months are usually first-year birds. Pacific Golden Plovers do not nest in Hawai'i.

Up until the early 1980's the Pacific Golden Plover and the American Golden Plover (Pluvialis dominica) were considered conspecific (one species) but intensive research revealed that the two species did not interbreed where the two species ranges overlap. For a long time, also, the identification of the two species was considered to be very problematic, but criteria for separating the two species is now well known and almost all birds should be identifiable in the field. The breeding and wintering ranges of the two species are very different: Pacific Golden Plovers breeding the Arctic across Siberia and Northern Asia, with a smaller population breeding in western Alaska; American Golden Plover breeds in Alaska and northern Canada and winters in South America. Interestingly no American Golden Plovers had ever been recorded in Hawai'i up to and including April 2002, despite the fact that the species is a long-distance migrant and has been recorded frequently as a vagrant considerable distances from either its winter or summer ranges (eg. Europe).

Description

In summer breeding plumage shows spangled gold and black upperparts with flecks of white and dark belly, breast and face. A white dividing line runs from the forehead down the neck sides to the breast side and then along the flanks, where it becomes less clear-cut and is barred. In winter and juvenile plumages the species exhibits plainer upperparts with only some showing slightly spangled upperparts. The underparts and facial area are plain and grey-brown in colour with a diffused supercilium and a pale area around the bill base. The legs and bill are dark in all plumages. It is the smallest and slimmest of the three Golden Plover species (the other being Eurasian Golden Plover (Pluvialis apricaria), which has not been recorded from Hawai'i either). Like the American Golden Plover it shows a smoky grey underwing in flight, including the axillaries, which are white in Eurasian. See table below for principal separation characteristics.

For a full account of moults and plumage differences between Pacific Golden, American Golden, Eurasian Golden and Grey (Black-bellied ) Plovers consult Cramp et al. (1983) or Hayman et al. (1986).

Voice: A range of loud monosyllabic or disyllabic calls. Sharper and less mellow than the calls of Eurasian Golden Plover. A rapid "tu-ee" or "chu-wit" recalling a Spotted Redshank and a plaintive "ki-ee" or "ki-wee", almost like Northern Lapwing, are the most useful for separation from Eurasian Golden.

Range

Pacific Golden Plovers breed in Siberian tundra from Yamal Peninsula eastwards and western Alaska. Their movements are more diffuse than in American Golden with many migrating south to south-east into the Central Pacific, whilst others move S to SSW into southern Asia and even to the Indian Ocean fringes. Major staging posts are the Pribilof Islands (Bering Sea) and Hawai'i (4500 km apart), while other birds use Great Circle route from eastern Asia, crossing Micronesia and western Pacific. The Plovers winter in Indonesia, most islands in Micronesia, Melanesia and Polynesia, as well as Australia and New Zealand.

Having such a far-flung wintering range obviously involves flying great distances, much of which is over open water. Birds which were sampled on Wake Island in April had fat levels estimated to be sufficient for a 10,000 km flight, although it is only 4000 km between there and Kamchatka (Cramp et al. 1983).

Movements

Adults leave the Arctic tundra in late July or early August. In the Pribilofs adults halt in August and juveniles in September. Most adults reach Hawaiian latitudes in August, although a few arrive in late July; arrive in Fiji in early September and New Zealand in October. An adult bird that was banded on the Pribilofs on 8th August was recorded on Kure Atoll, Hawai'i 26 days later (Woodward 1972). The major northward movement through Hawai'i occurs during April and birds reach the Pribilofs by the first half of May. Birds arrive back on their Arctic nesting grounds by mid-June. Birds inhabiting Asia during the winter fly to and from their nesting grounds overland.

The species has been recorded as a vagrant in South Africa, Europe, New England (USA) and Chile. Birds are now recorded annually in the U.K. and some years may see small influxes.

Habitat

During the breeding season the species is found mainly in Arctic and sub-Arctic tundra beyond the tree-limit. It is found along valleys and in well-drained stony uplands with gentle slopes and generally short vegetation, such as moss and lichen or on clayey tundra. After the chicks have hatched they move down to moister areas such as Sphagnum swamps. The young remain in these areas after the adults leave for their migration staging areas, which tend to be rolling pastures with short or scant grass cover, prairies, ploughed fields and mudflats. The young when they migrate tend to use migration stopovers such as mud by inland waters, tidal flats and saltmarsh.

On the wintering grounds birds may use a variety of habitats. In Hawai'i most birds tend to prefer short grass, open fields, airfields, football pitches and lawns, with smaller numbers on wetlands. In Argentina, American Golden Plovers are found on fields, farmland, wetlands and by slow-moving streams.

Although the species inhabits rather sparsely populated areas both during the summer and winter the species was persecuted by hunters in North and South America and its numbers decreased rapidly, although at present there is no threat to the species as numbers have recovered and hunting of the species is now banned in most areas.

As a regular and conspicuous migrant to the Hawaiian Islands the species has become one of the most popular "Hawaiian" birds amongst Islanders. Many residents await "their" birds to return from the nesting grounds and take up territory in their gardens, local parks, lawns and playing fields. It is possible to find the same individual returning year after year to the same patch of grass, which they vigourously defend from new arrivals. At night birds leave their territories and roost communally on wetlands, beaches and on rooves of buildings, such as warehouses and shopping centres.

The Pacific Golden Plover looks for food by making short runs with frequent stops, where it stabs at the ground to pick and consume beetles, grubs, worms, ants, other invertebrates, and sometimes vegetation.

Principal Characteristics for Separation of Golden Plovers.

	PACIFIC GOLDEN	AMERICAN GOLDEN	EURASIAN GOLDEN
AT ALL TIMES
Underwing and axillaries	Dull Grey.	Dull Grey.	Mostly White.
Wing tip v. Tail tip	Wings clearly longer.	Wings clearly longer.	Wings slightly longer than or equal to tail.
Size and Shape	Noticeably small and slim.	Fairly bulky.	Large, bulky, small-billed.
Leg Length	Relatively long, particularly above "knee".	Relatively long, particularly above "knee".	Relatively short, little tibia exposed.
BREEDING PLUMAGE
White flank line	Narrow, often inconspicuous.	Flanks mostly black with very little white.	Broad but irregular.
White "shoulder-patch" on sides of breast	Relatively small.	Large and conspicuous.	Absent or relatively small.
Undertail coverts	Blotched black and white.	Black or mainly black.	White or whitish, sometimes barred.
NON-BREEDING
Supercilium	Yellowish-buff, distinct.	Whitish, striking.	Buffish, indistinct.
Upperparts	Brown, spotted bright yellow.	Brown-grey, spotted whitish and pale yellow.	Pale brown, spotted yellowish.
Breast	Buffish, mottled bright yellow.	Dull greyish, mottled off-white.	Streaked dark grey-brown, mottled yellow.
JUVENILE
Supercilium	Whitish-yellow, conspicuous.	Whitish, conspicuous.	Buffish, inconspicuous.
Upperparts	Brown, spotted bright yellow.	Dark brown, spotted pale yellow and whitish.	Brown, spotted yellow.
Breast	Buff, mottled bright yellow.	Greyish, mottled white.	Pale brown, mottled yellow.
Underpart barring	Flanks only.	Upper belly and flanks.	Belly and flanks.
Central tail feathers	Narrowly spotted/edged pale yellow.	Narrowly spotted/edged pale yellow.	Broadly notched/barred yellow.

Table taken from Shorebirds. An identification guide to the waders of the world. Hayman et al. 1986.

Pacific Golden Plover Gallery

All photos below by Christian Melgar ©2001

References

CONNORS, P. G. 1983. Taxonomy, distribution and evolution of Golden Plovers (Pluvialis dominica and Pluvialis fulva). Auk 100: 607-620.

CRAMP, S. (Chief Editor) et al.. 1983. Handbook of the Birds of Europe, the Middle East and North Africa. The Birds of the Western Palearctic. Volume III. Waders to Gulls. Oxford University Press, Oxford, U.K.

HAWAII AUDUBON SOCIETY. 1997. Hawaii's Birds. The Hawaii Audubon Society, Honolulu, Hawai'i.

HAYMAN, P., J. MARCHANT and A. J. PRATER. 1986. Shorebirds. An Identification Guide to the Waders of the World. Christopher Helm, London.

JOHNSON, O. W. and R. W. MACFARLANE. 1967. Migration and bioenergetics of flight in the Pacific Golden Plover. The Condor 69: 156-168.

JOHNSON, O. W., P. M. JOHNSON, and P. L. BRUNER. 1981. Wintering behaviour and site-faithfulness of Golden Plover on O'ahu. In the 'Elepaio 41: 123-130.

PYM, A. 1982. Identification of Lesser Golden Plover and status in Great Britain and Ireland. British Birds 75: 112-124.

WOODWARD, P. W. 1972. Movements of Pacific Golden Plovers. Atoll Research Bulletin 164.

Christian Melgar. Worthing, West Sussex, UK. 2002.

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