Piping Plover

Charadrius melodus

Description

The piping plover is a stocky, short-billed shore-bird, about 7 in (17 cm) long. The sexes are similar in size and color. Plovers in breeding plumage are pale beige above and white below, with a black chest band and crown patch. The bill is orange, tipped with black, and the legs are bright orange. Piping plovers lose their black markings during the non-breeding season, when their bill is all black, and the leg color fades to yellow.

The American Ornithologists' Union recognizes two geographically separate subspecies of the piping plover: Charadrius melodus melodus and C. m. circumcinctus. Recent scientific studies, however, have detected little or no genetic difference between the groups. For this reason, the Fish and Wildlife Service treats these two "subspecies" as distinct breeding populations of the same species—one on the Atlantic coast of North America, the second scattered from the northern Great Plains into southern Canada.

Behavior

The piping plover is one of the earliest migratory birds to return to New England beaches, often arriving in early March. Characteristically, it darts across the sand on its stilty, orange legs, stopping suddenly to stab at prey with its beak, before darting off. Because its coloration blends so well with sandy beaches, its distinctive "piping" call—peeplo!—is often heard before the bird is seen.

The breeding season for piping plovers is from late March to August. During the courtship ritual, the male flies in figure-eights. On the ground it puffs up its feathers, and struts and whistles around the female, stretching its neck and stamping its feet. When nesting, a mated pair scoops out a depression on the beach above the high-tide line, sometimes lining it with small stones, shells, or driftwood. The female lays four pear-shaped, buff-colored eggs, marked with small spots of dark brown or black. Both parents incubate the eggs for about 30 days. The well camouflaged young leave the nest a few hours after hatching—as soon as their down is dry— and begin to feed on their own. Family groups stay together for about a month until the chicks fledge.

The diet of the piping plover consists mainly of small crustaceans, mollusks, and other tiny marine creatures, supplemented by beach insects.

Habitat

The piping plover nests on sand or pebble beaches, typically associated with large bodies of water. When nesting inland, the plover seeks out small islands and flats along major river systems or lakes, or finds undisturbed spots, such as abandoned gravel pits or salt-encrusted spits along alkali lakes.

Birds from the northern Great Plains and Great Lakes winter along the Gulf Coast. Populations that breed along the Atlantic coast winter from North Carolina southward, occasionally in the Bahamas and West Indies. Little is known of the habitat requirements of piping plovers on their wintering grounds.

Distribution

In 1804, the explorers Lewis and Clark observed the piping plover on sandbars in the Missouri River between Iowa and Missouri. At the turn of the century, this plover was described as common in Nebraska, where it bred along the Platte River and on the Loop River northwest of Grand Island. However, uncontrolled hunting soon led to depletion of these breeding populations. As human disturbance of nesting areas increased, the range of the piping plover shrank northward into Canada and along the northern Great Lakes. In 1912, the piping plover was a common summer resident along the Lake Michigan shoreline in Illinois, but it no longer breeds there. In Michigan, the plover declined to a 1984 low of only 13 pairs. At Long Point, Ontario, a large population was reduced to zero by the late 1970s. The Atlantic coast population has also experienced a serious decline, principally because of habitat loss due to beachfront development and recreational activities. For example, the number of breeding pairs on Long Island, New York, declined from more than 500 in the 1930s to a recent population of about 100. Nesting is increasingly confined to rare undisturbed stretches of beach.

In 1980, about 900 pairs of piping plovers were estimated to breed along the Atlantic coast from Newfoundland to North Carolina. A 1986 census estimated 550 pairs along the U.S. Atlantic coast, and 240 pairs in eastern Canada. Over 80% of the breeding population nests in Massachusetts, New York, New Jersey, and Virginia.

As of 1995, the piping plover population in the New England recovery unit had reached 89% of the recovery goal (555 pairs) specified in the 1995 draft recovery plan. Furthermore, under an intensive management program, the Massachusetts piping plover population had increased more than threefold over the previous eight years, from 126 pairs in 1987 to 445 pairs in 1995. Less progress has occurred throughout the rest of the range of the piping plover. Sub-populations in Canada and the southern portion of the range actually decreased between 1987 and 1995. While the overall status of the population remains precarious, the apparent recovery in New England demonstrates that recovery is possible. At the northern extent of its range, piping plovers continue to breed on Newfoundland's southern coast, although they were not located on the northeast or western coasts of Newfoundland, the Gaspé Peninsula, or the Gulf of Saint Lawrence during the 1991 International Census. The recent sparseness of nesting pairs is of particular concern in the southern part of the Atlantic Coast range. Although the New Jersey population increased between 1986 and 1989 and has remained stable since, the proportion of the State's population located in three areas administered by the National Park Service and the U.S. Fish and Wildlife Service has increased from 24% in 1987 to 49% in 1994. The proportion of birds nesting in the southern part of New Jersey during the same period declined from 43% to 31%. Only two to four pairs of plovers nested in Delaware between 1992 and 1994, compared with about 40 birds nesting in the State in 1980. Assateague Island, Maryland, is now the nearest nesting site south of Delaware. Only two pairs nested on Currituck Outer Banks in 1994, the sole remaining breeding site between Fishermans Island, Virginia, on the northern side of the Chesapeake Bay, and Cape Hatteras Point, North Carolina.

Inland, an unknown but small number of piping plovers is found in northeastern Montana and along the Missouri River system in the Dakotas and Nebraska. Around the Great Lakes, where the species is listed as Endangered, populations are at critical lows: in 1988, 24 pairs of plovers were found in Lake of the Woods, 22 in Minnesota and two in Ontario. In Canada the species is most numerous in Saskatchewan, but in Manitoba only 20% of historic nesting sites are currently in use.

Threats

Protected by the Migratory Bird Treaty Act, the piping plover recovered from the effects of hunting during the 1920s, only to fall prey to a range of other human-caused and natural factors.

Most of the recent decline of this ground nester has been caused by human disturbance of its habitat. Beachfront development and recreation has expanded greatly along beaches of the Great Lakes and Atlantic coast. Home building and road construction have destroyed suitable nesting habitat outright. Swimmers and beach hikers disturb plover nests and disrupt incubation. Unleashed pets on the beaches kill plover chicks and destroy eggs. Accumulation of debris and garbage has attracted such predators as foxes, feral dogs and cats, opossums, skunks, and rats.

Inland populations declined when large-scale water control projects along major rivers drastically altered breeding habitat of the piping plover. The few remaining riverine islands that would be suitable for nesting are now used for recreation. Human disturbance in the form of off-road vehicles is even reaching into the remote, sparsely populated alkali wetland country of the Dakotas, Montana, and Saskatchewan. Natural predators, such as the raccoon and gulls, have greatly expanded their ranges since the 1940s, increasing chick and egg mortality of the piping plover.

Another threat, still present in 2000, comes from the potential for hazardous materials spills. This was illustrated in June, 1990, when the oil tanker B.T. Nautilus ran aground in the Kill Van Kull waterway between New Jersey and New York, spilling some 267,000 gallons (1,014,000 l) of fuel oil into the Kill Van Kull and adjacent waterways. Along with the damage to recreational beaches, the spill threatened piping plovers nesting in the area at the time of the spill. A settlement was reached with the shipping company to pay for damages in 1993, with a payment of $3.3 million in compensation for natural resource injuries. Settlement for injuries to populations of the piping plover accounted for a major component of the damage claim.

The original FWS Recovery Plan for the Atlantic coast population set a goal of increasing the population to 1,200 breeding pairs. In 1995, on the basis of data gathered over the previous 7 years, the plan was revised to call for increasing the recovery and delisting target to 2,000 breeding pairs. At the same time, investigators proposed a program to allow additional management flexibility and reduce the impacts of plover protection on beach recreation.

Conservation and Recovery

If the population goal numbers can be maintained for five consecutive years, the piping plover would be considered for delisting. To accomplish this, FWS biologists are continuing to monitor population trends through yearly surveys. Individual nesting sites have been examined and management programs established for sites on public land. Additional sections of beach in wildlife refuges may be declared "off limits" for the plover breeding season, a step already taken for some beaches in Massachusetts, Rhode Island, Connecticut, New Jersey, and Virginia.

The Great Lakes/Northern Great Plains (GL/NGP) Recovery Team has developed a recovery plan and makes management recommendations for those two plover populations. The Atlantic Coast Recovery Team fulfills an identical role for plovers along the East Coast. Furthermore, two Canadian Recovery Teams provide guidance for activities to recover Atlantic Coast and Prairie piping plovers in that country; coordination of recovery activities between the two countries is facilitated through an exchange of observers (i.e., non-members) among recovery teams and frequent communications. The piping plover is listed as Endangered by the Committee on the Status of Endangered Wildlife in Canada.

The primary objective of the revised (1994) recovery program is to remove the Atlantic Coast piping plover population from the List of Endangered and Threatened Wildlife and Plants by: (1) achieving well-distributed increases in numbers and productivity of breeding pairs, and (2) providing for long-term protection of breeding and wintering plovers and their habitat. Efforts to reduce nest disturbance by pedestrians, off-road vehicles, and predators have included fencing, limiting recreational use, rerouting of off-road vehicles, enforcing pet-leash rules, removing litter and garbage, and removing predators. In addition, an existing public information program is being expanded to alert beach dwellers and recreational users to possible harm they can cause the piping plover. As part of this program, public service announcements will be made on local television and radio stations in Nebraska to alert the public to the presence of plovers on the Platte River. Plover alert posters will be displayed in businesses that sell recreational equipment and all-terrain vehicles. The Southeast Region of the FWS is also developing a regional Recovery Plan for the piping plover. This is being done within the context of a broader Recovery Plan for 68 threatened and endangered species occurring in south Florida.

Another recovery tool, this one a high-tech innovation, is also being used to benefit the piping plover. In 1993, FWS biologists began using Geographic Information System (GIS) techniques to map out potential piping plover habitat over a three-county wetland area in North Dakota. The GIS models developed proved both effective and accurate—subsequent field surveys identified piping plover occurrences at two previously unknown sites. Although the program also failed to identify habitats where some known piping plover populations existed, it has continued to be a helpful tool in the location process. According to 1996 data, surveys had detected piping plovers during the breeding season on over 100 wetlands in North Dakota.

Contacts

U.S. Fish and Wildlife Service
Division of Endangered Species
Adminstrative Office
Federal Building
1 Federal Drive
Fort Snelling, Minnesota 55111-4056
Telephone: (612) 713-5360
Fax: (612) 713-5292

U.S. Fish and Wildlife Service
Asheville Ecological Services Field Office
Asheville, North Carolina 28801-1082
Telephone: (828) 258-3939
Fax: (828) 258-5330

References

Cairns, W. E., and I. A. McLaren. 1980. "Status of the Piping Plover on the East Coast of North America." American Birds 34: 206-208.

Graham, F., Jr. 1986. "Cry of the Plover." Audubon 88(3): 12-17.

Haig, S. M., and L. W. Oring. 1987. "The Piping Plover." In R. L. Di Silvestro, ed., Audubon Wildlife Report 1987. Academic Press, New York.

U.S. Fish and Wildlife Service. 1988. "Atlantic Coast Piping Plover Recovery Plan." U.S. Fish and Wildlife Service, Newton Corner, Massachusetts.

U.S. Fish and Wildlife Service. 1988. "Great Lakes and Northern Great Plains Piping Plover Recovery Plan." U.S. Fish and Wildlife Service, Twin Cities.