Habitat
Wilson’s Plovers occupy salt flats and sandy beaches or barrier islands year-round. They nest above the high-tide mark, usually not far from dunes. They also use human-made habitats such as dredge spoil islands. They forage in the muddy margins of coastal lagoons, especially where prey such as fiddler crabs is abundant, as well as in dry or moist impoundments, salt evaporation ponds, and construction areas with open ground. Sea oats, sea rocket, glasswort, saltwort, beach elder, and saltmeadow cordgrass are common plants in these habitats. When not foraging, Wilson’s Plovers often rest in small groups in areas of high beach with abundant shells. In South America, they also use mangroves, roadways, and rock jetties for roosting.
Back to topFood
Wilson’s Plover eat insects, crustaceans, and other marine invertebrates, which they glean or pull from mud or sand using the bill. They forage during the day and also at night, usually on a falling tide, which exposes their favored prey, fiddler crabs. They run and lunge to catch a crab, then shake it to remove the legs before swallowing it. In some places, fiddler crabs make up 99% of this species’ diet. Like other plovers in this environment, they also eat marine worms, sand flies, dragonflies, shrimp, and tiny mollusks.
Back to topNesting
Nest Placement
Males make several simple scrapes on the ground in a sandy or shelly spot, occasionally next to a bit of driftwood or other debris, in a very sparsely vegetated area. Females select one of these scrapes for the nest. Some nests are sited in gravelly road edges.
Nest Description
Most nests are bare scrapes; some have shells, wrack (decaying marine algae and other vegetation), pebbles, and gravel at the base of the cup or around the edges. Scrapes average about 3.2 inches across.
Nesting Facts
| Egg Description: | Cream to buff, speckled heavily with black, dark brown, or gray. |
| Condition at Hatching: | Covered in down, weighing about 0.3 ounces, able to walk within 2 hours. |
Behavior
Wilson’s Plovers appear to be monogamous. Birds often arrive on nesting grounds already paired up. Males make several scrapes for females to investigate as nest sites. When the female approaches a male making a scrape, he fans the tail, points to the scrape with the bill, then extends and points to the scrape with the wing nearest to it, raising the other wing high above his head and giving a dovelike cooing call. Sometimes males prance around the scrape and puff out the breast. Males warn intruding males with posturing and parallel running displays, sometimes chasing them away on foot or in flight. Both male and female defend a nesting territory against intruders (including other Wilson’s Plovers and smaller species), and they join with neighboring pairs to attack or distract a common enemy such as a fox, raccoon, or gull. These groups communicate about potential threats with high-pitched calls, and multiple birds may perform broken-wing displays to draw predators away from eggs and chicks. Both adults share incubation and chick-rearing duties. Once young are fledged, pairs and their young often roost and forage in loose assemblages that also cooperate in defense against predators.
Back to topConservation
Wilson’s Plovers appear to be declining over much of their range. Partners in Flight estimates a global breeding population of 22,000 and rates the species a 16 out of 20 on the Continental Concern Score, placing the species on the Yellow Watch List for species with restricted ranges. A 2012 assessment estimated a U.S. breeding population of 8,600 breeding birds. Wilson’s Plover is listed as threatened or endangered in some states. The loss and degradation of nesting and foraging habitats have been severe in the case of this species, which favors habitats that attract beachgoing tourists and beachfront development. People or dogs trespassing into protected reserves during the nesting season is a frequent cause of nesting failure. The arrival of nesting Peregrine Falcons in beach areas of the Atlantic coast has caused increased predation of Wilson’s Plovers. Erosion and loss of habitat to rising sea levels are probably the chief conservation threats to this species.
Back to topCredits
Andres, B. A., P. A. Smith, R. I. G. Morrison, C. L. Gratto-Trevor, S. C. Brown, and C. A. Friis (2012). Population estimates of North American shorebirds, 2012. Wader Study Group Bulletin 119:178–194.
Corbat, Carol A. and Peter W. Bergstrom. (2000). Wilson's Plover (Charadrius wilsonia), version 2.0. In The Birds of North America (P. G. Rodewald, editor). Cornell Lab of Ornithology, Ithaca, New York, USA.
Lutmerding, J. A. and A. S. Love. (2020). Longevity records of North American birds. Version 2020. Patuxent Wildlife Research Center, Bird Banding Laboratory 2020.
Sibley, D. A. (2014). The Sibley Guide to Birds, second edition. Alfred A. Knopf, New York, NY, USA.