Diet and Foraging

Main Foods Taken

The American Golden-Plover feeds on invertebrates, primarily terrestrial, some freshwater and marine; also berries, leaves, and seeds. Studies on other shorebirds (200 Proctor, V. H. (1968). Long-distance dispersal of seeds by retention in the digestive tract of birds. Science 160:321–322. Close ) suggest that these plovers might retain seeds in their digestive tract, transporting them over great distances during migrations. Small vertebrates are known to be eaten occasionally by the Pacific Golden-Plover (Pluvialis fulva), and also possibly by the American Golden-Plover, but definite evidence is lacking. On breeding grounds near Churchill, Manitoba, the American Golden-Plover tends to forage selectively on relatively large prey (201 Baker, M. C. (1977). Shorebird food habits in the eastern Canadian Arctic. Condor 79:56–62. Close ).

Microhabitat for Foraging

Foraging habitat varies with the annual cycle and geographic location. The American Golden-Plover generally prefers microhabitats where plant cover is short or absent, allowing ease of movement and relatively unobstructed vision. Breeding birds forage on various types of tundra, ranging from large expanses of low vegetation only a few centimeters tall (as on well-drained slopes) to wetter mosaics of low shrubs and grasses interspersed with openings. When the young hatch, families move to moist shrub/grass areas for feeding and cover. Migrants and overwintering birds feed on a wide array of substrates (see Habitat). At spring stopover in northern Indiana and Illinois, birds seemed to prefer soybean stubble, possibly because less insecticide is used on this crop, resulting in greater abundance of soil insects (181 Erickson, H. T. (1992). Spring migration of Lesser Golden-Plovers in Benton County, Indiana. Indiana Audubon Quarterly 70:87–92. Close ). More recently, a similar preference was demonstrated for soybean fields, especially those with ephemeral water that likely makes earthworms more accessible (62 Stodola, K. W., B. J. O'Neal, M. G. Alessi, J. L. Deppe, T. R. Dallas, T. A. Beveroth, T. J. Benson, and M. P. Ward (2014). Stopover ecology of American Golden-Plovers (Pluvialis dominica) in Midwestern agricultural fields. Condor 116:162–172. Close ). The bird is attracted to rice fields on overwintering range in South America (132 Blanco, D. E., B. López-Lanús, R. A. Dias, A. Azpiroz, and F. Rilla (2006). Use of rice fields by migratory shorebirds in southern South America: Implications for conservation and management. Wetlands International, Buenos Aires, Argentina. Close ).

Food Capture and Consumption

The American Golden-Plover forages by a repeated sequence of "stop-run-stop" or "run-stop-peck" (31 Byrkjedal, I., and D. B. A. Thompson (1998). Tundra Plovers: The Eurasian, Pacific and American Golden Plovers and Grey Plover. T & AD Poyser Ltd, London, United Kingdom. Close ). At stop, prey is captured (usually after brief scanning of the substrate), or the capture attempt fails, or no prey is seen. Capture is with a single peck or series of pecks. Probing while feeding on earthworms has been reported (202 Wishart, R. A., P. J. Caldwell, and S. G. Sealy (1981a). Feeding and social behavior of some migrant shorebirds in southern Manitoba. Canadian Field-Naturalist 95:183–185. Close ); possible tactile feeding by shallow poking in mud has also been noted (7 Paulson, D. R. (1993). Shorebirds of the Pacific Northwest. University of Washington Press, Seattle, Washington, USA. Close ).

Probably most food recognition and choice are related to eyesight. Except for brief comments about probing above, there is no information concerning senses of taste, smell, or touch. Berry-eating on the tundra does not involve the usual foraging behavior just described; instead the bird pecks repeatedly in a small area. Birds foraging amidst low bushes on breeding grounds sometimes peck leaves at eye level or above, likely capturing tiny spiders or insects (probably mosquitoes which were abundant when this behavior was observed, O. W. Johnson). Spatial separation is maintained during feeding - no cooperative foraging. Foraging behavior varies with reproductive duties: if incubation is underway, birds forage alone during off-duty hours; if not yet incubating or if eggs have hatched and parents are guarding the young, mated birds usually forage together.

Overwintering birds feed alone on territories well separated from neighbors, or in more closely spaced groups (see Behavior: Spacing). The general pattern is to return to the feeding grounds before sunrise, forage during daylight hours, then gather at communal roosts for the night (see Behavior: Self-Maintenance).

Major Food Items

The American Golden-Plover feeds on various adult and larval insects such as grasshoppers, beetles, grubs, cutworms, wireworms, earthworms (southern Manitoba, 202 Wishart, R. A., P. J. Caldwell, and S. G. Sealy (1981a). Feeding and social behavior of some migrant shorebirds in southern Manitoba. Canadian Field-Naturalist 95:183–185. Close ; Illinois/Indiana 62 Stodola, K. W., B. J. O'Neal, M. G. Alessi, J. L. Deppe, T. R. Dallas, T. A. Beveroth, T. J. Benson, and M. P. Ward (2014). Stopover ecology of American Golden-Plovers (Pluvialis dominica) in Midwestern agricultural fields. Condor 116:162–172. Close ), small mollusks and crustaceans, spiders, crowberries (Empetrum spp.), and blueberries (Vaccinium spp.) (203 Bent, A. C. (1929). Life histories of North American shorebirds, Part 2. United States National Museum Bulletin 146. Close , 31 Byrkjedal, I., and D. B. A. Thompson (1998). Tundra Plovers: The Eurasian, Pacific and American Golden Plovers and Grey Plover. T & AD Poyser Ltd, London, United Kingdom. Close ). Regional reports list numerous foods including: seeds of Sylibum marianum (Argentina, 48 Dabbene, R. (1920). Notas sobre los chorlos de Norte América que invernan en la República Argentina. Hornero 2:99–128. Close ), berries of Arctostaphylos uvaursi, spiders (Lycosa sp.), weevils (Otiorhynchus ovatus), ichneumon wasps, beetle larvae (Nantucket Island, 204 Mackay, G. H. (1892d). The migration of Charadrius dominicus in Massachusetts in 1891. Auk 9:199–200. Close , 205 Mackay, G. H. (1929). Shooting journal of George Henry Mackay 1865–1922. Cosmos Press, Cambridge, MA, USA. Close ), fiddler crabs (Uca uruguayensis) (Argentina, 206 Iribarne, O. O., and M. M. Martinez (1999). Predation on the southwestern Atlantic Fiddler Crab (Uca uruguayensis) by migratory shorebirds (Pluvialis dominica, P. squatarola, Arenaria interpres, and Numenius phaeopus). Estuaries 22:47–54. Close ), ants (Illinois, 207 Brooks, W. S. (1967). Organisms consumed by various migrating shorebirds. Auk 84:128–130. Close ), flies, crickets, isopods, snails, plant parts (Argentina, 208 Isacch, J. P., C. A. Darrieu, and M. M. Martínez (2005). Food abundance and dietary relationships among migratory shorebirds using grasslands during the non-breeding season. Waterbirds 28:238–245. Close ). Berries are particularly important in spring and fall. At spring arrival, berries from the previous year may be one of few foods available. The latter are sometimes very abundant, with densities reaching 200,000/ha (209 McCaffery, B. J. (1996). The status of Alaska's large shorebirds: A review and an example. In Shorebird Ecology and Conservation in the Western Hemisphere (P. Hicklin, Editor). International Wader Studies 8:28–32. Close ). The new berry crop is used by fall migrants during stopovers (210 Mackay, G. H. (1891). The habits of the Golden Plover (Charadrius dominicus) in Massachusetts. Auk 8:17–24. Close , also see 184 Todd, W. E. C. (1963). Birds of the Labrador Peninsula and Adjacent Areas: A Distributional List. University of Toronto Press, Toronto, ON, Canada. Close ), and no doubt by juveniles remaining on breeding grounds after the departure of the adults (see Movements and Migration: Timing and Routes of Migration). Fallout of airborne arthropods on snow patches could provide a limited early-spring food source (211 Edwards, J. S., and P. C. Banko (1976). Arthropod fallout and nutrient transport: a quantitative study of Alaskan snowpatches. Arctic and Alpine Research 8:237–245. Close ).

Quantitative Analysis

On Nantucket Island "many" stomachs from birds shot during fall migration were filled with little else than crickets (210 Mackay, G. H. (1891). The habits of the Golden Plover (Charadrius dominicus) in Massachusetts. Auk 8:17–24. Close ); at Churchill, Manitoba, 13 individuals had eaten approximately 41% plant seeds, 20% unidentified snails, 17% Chironomidae larvae, 9% Tipulidae larvae, 5% Dolichopodidae larvae, 5% Chrysomelidae (Donacia sp.) adults, 1% Diptera eggs, 1% Dysticidae (Agabus sp.) larvae, and 1% unidentified adult Coleoptera (201 Baker, M. C. (1977). Shorebird food habits in the eastern Canadian Arctic. Condor 79:56–62. Close ).

Lemming bones (presumably scavenged from pellets and scats of predators) are occasionally found in plover stomachs, hence this material may be a calcium source for eggshell production and growth of juveniles (see 212 Underhill, L. G. (1994). Reviving the calcium-from-lemmings hypothesis. Wader Study Group Bulletin 75:35–36. Close ). Stomach samples from the European Golden-Plover (Pluvialis apricaria) suggest that females ingest bones, but males do not (31 Byrkjedal, I., and D. B. A. Thompson (1998). Tundra Plovers: The Eurasian, Pacific and American Golden Plovers and Grey Plover. T & AD Poyser Ltd, London, United Kingdom. Close ); there is no comparable data for the American Golden-Plover. Since small bones are not predictably available, and since stomachs from shorebirds collected on tundra breeding grounds often contain no calcareous material (213 Piersma, T., G. A. Gudmundsson, N. C. Davidson, and R. I. G. Morrison (1996e). Do arctic-breeding Red Knots (Calidris canutus) accumulate skeletal calcium before egg laying? Canadian Journal of Zoology 74:2257–2261. Close , 124 Jehl, J. R., Jr. (2004a). Birdlife of the Churchill Region: Status, History, Biology. Trafford, Victoria, BC, Canada. Close ), it remains uncertain how females acquire sufficient calcium for egg-laying, which sometimes includes a replacement clutch (see Demography and Populations: Measures of Breeding Activity). There is no information on body mass of these plovers at arrival on nesting grounds, and the energy demands associated with breeding (e.g., egg-laying, incubation) have not been explored. Based on studies of other shorebirds (214 Klaassen, M., A. Lindstrom, H. Meltofte, and T. Piersma (2001). Ornithology– Arctic waders are not capital breeders. Nature 413(6858):794. Close , 215 Morrison, R. I. G., and K. A. Hobson (2004). Use of body stores in shorebirds after arrival on High-Arctic breeding grounds. Auk 121:333–344. Close , 216 Tulp, I. (2007). The arctic pulse. Timing of breeding in long-distance migrant shorebirds. Ph.D. dissertation, University of Groningen, The Netherlands. Close ), energy stores at arrival on breeding grounds (capital) may be partly used for egg production, but the latter is likely to depend mostly on nutrients acquired after arrival (income). Eggs sampled at Churchill, Manitoba, suggested that at least some components were from endogenous stores (217 Hobson, K. A., and J. R. Jehl (2010). Arctic waders and the capital-income continuum: Further tests using isotopic contrasts of egg components. Journal of Avian Biology 41:565–572. Close ).

Studies of overwintering adult Pacific Golden-Plover (218 Mathiu, P. M., O. W. Johnson, P. M. Johnson, and G. C. Whittow (1989). Basal metabolic rate of Pacific Golden-Plovers. Wilson Bulletin 101:652–654. Close ) showed a high (passerine-like) basal metabolic rate (BMR) at 1.31W ± 0.41 SD, n = 12; mean rectal temperature 40.5°C ± 0.6 SD, n = 11; and average rate of weight loss during captivity 0.61 g/h ± 0.13 SD, n = 9; BMR may be higher on nesting grounds (see 219 Lindström, A., and M. Klaassen (2003). High basal metabolic rates of shorebirds while in the arctic: A circumpolar view. Condor 105:420–427. Close ). There are no comparable measurements for the adult American Golden-Plover. Metabolic rates, temperature regulation, time budgets, and body temperatures in relation to ambient temperatures have been studied in American Golden-Plover chicks (220 Visser, G. H., and R. E. Ricklefs (1993b). Temperature regulation in neonates of shorebirds. Auk 110:445–457. Close , 221 Krijgsveld, K. L., J. W. H. Reneerkens, G. D. McNett, and R. E. Ricklefs (2003). Time budgets and body temperatures of American Golden-Plover chicks in relation to ambient temperature. Condor 105:268–278. Close , 222 Williams, J. B., B. I. Tieleman, G. H. Visser, and R. E. Ricklefs (2007). Does growth rate determine the rate of metabolism in shorebird chicks living in the arctic? Physiological and Biochemical Zoology 80:500–513. Close ; see Breeding: Parental Care). Visser and Ricklefs (220 Visser, G. H., and R. E. Ricklefs (1993b). Temperature regulation in neonates of shorebirds. Auk 110:445–457. Close ) measured resting metabolic rate (RMR) and peak metabolic rate (PMR) in one neonate at 0.126W and 0.200W, respectively. Williams et al. (222 Williams, J. B., B. I. Tieleman, G. H. Visser, and R. E. Ricklefs (2007). Does growth rate determine the rate of metabolism in shorebird chicks living in the arctic? Physiological and Biochemical Zoology 80:500–513. Close ) tracked these rates from neonates to immature birds weighing about 80 g: approximate RMR increased from 10 to 100 kJ/day (n = 19), and approximate PMR increased from 25 to 300 kJ/day (n = 17). Energy requirements considerably in excess of predicted levels have been demonstrated in chicks of arctic-breeding shorebirds, including the American Golden-Plover (223 Schekkerman, H., I. Tulp, T. Piersma, and G. H. Visser (2003). Mechanisms promoting higher growth rate in arctic than in temperate shorebirds. Oecologia 134:332–342. Close ), such requirements are associated with cold tolerance, rapid growth rates, and reproduction timed to arthropod abundance.

Requirements for drinking are unknown. Large flocks of American Golden-Plovers gathered daily noon to mid afternoon for drinking and bathing at freshwater wetlands on Argentine overwintering range (49 Hudson, W. H. (1920) Birds of La Plata. Volume 1. Dent & Sons, London, United Kingdom. Close , 147 Myers, J. P., and L. P. Myers (1979). Shorebirds of coastal Buenos Aires Province, Argentina. Ibis 121:186–200. Close ). Skull morphology indicates that the American Golden-Plover has smaller supraorbital glands than the Pacific Golden-Plover, a difference suggesting the latter is better adapted to marine environments during the non-breeding season (31 Byrkjedal, I., and D. B. A. Thompson (1998). Tundra Plovers: The Eurasian, Pacific and American Golden Plovers and Grey Plover. T & AD Poyser Ltd, London, United Kingdom. Close ).

There are no reports of pellet-casting, but occasional regurgitation of pellets or unconsolidated particles may occur, based on observations in other shorebirds. Nothing unusual has been noted concerning defecation.