Plovers (Charardriidae)
Copyright © Diane L. Schirf
Plovers (Charardriidae) are plumpish small to medium-sized shorebirds, ranging in size from 14–41 cm to 34–296 g. Males are usually slightly larger than females. They are found virtually worldwide except for areas that are permanently frozen.
Plovers inhabit coastal, marshland, inland, river, and grassland to mountain and tundra regions. Their underparts are usually light colored, often with striking features on the head and neck. Despite its bold color patterns, their plumage is disruptive, and individuals blend into the background when they stand still. Body feathers molt twice a year, once after breeding season, with flight feathers molting once.
They have rounded heads and large eyes. Their legs, which can be black, flesh-colored, red, or yellow, are medium to long, and they are quick runners and strong fliers. The hind toe is small or absent. Most species have short, unwebbed front toes. There are 62 species in 10 genera.
The plover diet consists of terrestrial and aquatic invertebrates (including adult and larval insects, crustaceans, mollusks, and worms) and occasionally berries. For migratory species, the wintering ground diet differs widely from the breeding ground diet. With only one exception, the white-tailed lapwing, plovers do not wade in water in the same way or to the same extent as other shorebirds; most walk in damp areas or along the water’s edge, while some species are adapted for feeding in more arid areas away from water altogether. They use their keen eyesight to spot prey, then quickly run forward to catch it.
Plovers pair on or shortly after arrival at their feeding grounds. Some species nest in colonies of several hundred pairs, while others nest in small groups and defend relatively large territories. Displays are important in courtship, as evidenced by ornaments such as crests; prominent, colorful facial wattles; and well-developed wing spurs in some species. In the air, they twist, plunge, dive, and hover, while on the ground they run, wing-drop, tail-fan, and bow and curtsey, especially the males during scrape making, accompanied by much vocalization. The male creates scrapes on open, bare or slightly vegetated ground, and the female chooses one in which to lay.
Typically, with a few exceptions, four large, pear-shaped eggs representing 50–70 percent of the female’s body weight are laid over one-and-a-half to four days. Both parents usually incubate the clutch, beginning with the last egg laid. For smaller species, incubation is 18–22 days; for larger, it is 28-38 days. Both eggs and young are well camouflaged and are vigorously defended by the parents. Plovers are noted for their broken-wing display, by which the adult feigns a broken wing in an attempt to lure potential predators away from the nest. Natural threats to nests include flooding, especially if the nest is close to the water, and predation. The young are precocial and fledge at 21–42 days. Juveniles molt a few weeks after fledging.
Within a species, northern populations tend to migrate, while southern populations are virtually sedentary. Plovers migrate in flocks of thousands. Before migration, they acquire lots of subcutaneous body fat.
Exhibit and Collection History
The sand, or true, plovers (Charadrius), which are at the lower end of the size range, are found along sandy or muddy shores, along rivers, and inland in fields. Most true plovers feature a black chest band, black forehead, and black band from eye to bill. Sand plovers in zoos include the endangered shore plover of New Zealand (C. novaeseelandiae); the endangered piping plover of Canada and the U.S. (C. melodus and C. melodus circumcinctus); the killdeer of southern Canada-northern Chile (C. vociferus); the snowy/Kentish plover worldwide (C. alexandrinus); the Kentish plover of Mexico, Peru, and Chile (C. nivosus); the ringed plover of the Old World (C. hiaticula); Kittlitz’s sandplover of east, central, and south Africa (C. pecuarius); the Australian plover of south Australia and Tasmania (C. rubricollis); the semipalmated plover of Alaska (USA)–Argentina (C. semipalmatus); and the chestnut-banded sand plover of Kenya and Tanzania (C. venustus).
Vanellus plovers, or lapwings, are medium-sized plovers found primarily inland in most tropical and temperate regions, except North America. Lapwings often have a crest, wattles, and/or wing spurs. Vanellus plovers can be found in zoos worldwide and generally seem to breed well in captivity. Representative zoo species include the white-headed plover of south and west Africa (V. albiceps); the grey-headed lapwing of Siberia-India and Southeast Asia (V. cinereus); the northern lapwing of northern Africa and Eurasia (V. vanellus); the southern lapwing of South America (V. chilensis); the crowned lapwing of southern Africa (V. coronatus); the crowned plover of Ethiopia-Angola (V. coronatus coronatus); the long-toed lapwing of Sudan-Zimbabwe (V. crassirostris); the red-wattled lapwing of Southeast Asia and India (V. indicus and V. indicus atronuchalis); the masked lapwing of Australia, New Guinea, and New Zealand (V. miles); the banded plover of Australia and Tasmania (V. tricolor); and the spur-winged lapwing of northern Africa-Southeast Asia (V. spinosus).
The Pluvialis plovers are the largest. They breed at freshwater marshes and grasslands in upland and tundra regions of the Northern Hemisphere. The American plover, P. dominica dominca, is known for its long migration from the Arctic across the Atlantic to Argentina and across the Pacific to Australia. One population flies from Alaska to Hawaii, a distance of 4,500 km. Pluvialis plovers found in zoos include the greater golden plover of Europe and Asia (P. apricaria); the lesser golden plover, found virtually worldwide (P. dominca); the aforementioned American golden plover; the Pacific golden plover of northern Siberia-Australia (P. fulva); the New Zealand dotterel (P. obscura); and the black-bellied plover, worldwide (P. squatarola).
A species not in these genuses found in several zoos around the world is the blacksmith plover of south Angola-Kenya and Natal (Anitibyx armatus), which had been classified previously as a Vanellus plover.
Conservation Organizations and Partnerships
Past threats to plovers have included egg collecting and trapping of adults after breeding season, especially in Europe, and hunting. Current threats to plovers include loss and degradation of habitat, development of nesting areas, human disturbance of nests (for example, destruction by recreational vehicles), and hazards such as flooding.
In 1986, the Great Lakes population of the piping plover was listed as endangered, while the Northern Great Plains and Atlantic Coast populations were listed as threatened in the same year. The Northern Great Plains population became a front-page story (and a commemorative U.S. postage stamp) in the mid-1990s when Lincoln Park Zoo (Chicago, Illinois, USA) and the Milwaukee County Zoo (Milwaukee, Wisconsin, USA) were asked to participate in an egg rescue from plover nesting grounds in the upper Missouri River Basin after near record precipitation and above-normal mountain snow pack caused high basin runoff and threatened the loss of an entire breeding season.
Under the direction of the U.S. Army Corps of Engineers and the U.S. Fish and Wildlife Service, 30 eggs were collected in North and South Dakota. Detailed records were kept on each egg that would help keep track of the birds throughout their lives.
At this time, four adults hatched from those eggs reside at Lincoln Park Zoo. Two offspring, both female, one from each pair, have been sent to the Milwaukee County Zoo to be paired with piping plovers there. The successful reproduction of this species in captivity provides hope that zoos will learn enough about plover management and husbandry to save and preserve not only the piping plover, but other declining plover species as well.
Further reading:
Johnsgard, Paul A. The Plovers, Sandpipers, and Snipes of the World. University of Nebraska Press. Lincoln and London, 1981.
Perrins, Dr. Christopher M. and Dr. Alex L. A. Middleton. The Encyclopedia of Birds. Facts on File. Oxford and New York, 1985.
ISIS abstracts.
“Lincoln Park Zoo helps the Piping Plover.”
2001
An edited version of this article was published in Encyclopedia of the World’s Zoos, April, 1, 2001, winner of the Outstanding Reference Source award for 2001 from the American Library Association.
Comments
Plovers (Charardriidae) — No Comments
HTML tags allowed in your comment: <a href="" title=""> <abbr title=""> <acronym title=""> <b> <blockquote cite=""> <cite> <code> <del datetime=""> <em> <i> <q cite=""> <s> <strike> <strong>