Western snowy plover | |
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Scientific classification | |
Domain: | Eukaryota |
Kingdom: | Animalia |
Phylum: | Chordata |
Class: | Aves |
Order: | Charadriiformes |
Family: | Charadriidae |
Genus: | Anarhynchus |
Species: | |
Subspecies: | A. n. nivosus |
Trinomial name | |
Anarhynchus nivosus nivosus (Cassin, 1858) |
The western snowy plover (Anarhynchus nivosus nivosus) is a small wader in the plover bird family. They are currently federally listed under the U.S. Endangered Species Act as Threatened. [2] Human activity, habitat loss and predation are the biggest contributors to population degradation. A recovery plan was approved under the US Fish and Wildlife Service in 2007. Recovery actions and monitoring are crucial for these vulnerable seabirds. [3]
The western snowy plover was originally described by American ornithologist John Cassin (1858). Western snowy plover is a subspecies of the Snowy Plover (Anarhynchus nivosus), of the genus Anarhynchus (plovers). The species name nivosus comes from the Latin word 'niveus' meaning 'snowy'. [4]
The snowy plover is split into two species based on genetic analysis and phenotyping, a New World species now named the Snowy Plover (Anarhynchus nivosus), and an Old World species now named the Kentish Plover (Anarhynchus alexandrinus). [5]
Western snowy plovers are experts at blending into their environment. Plovers are shades of tan, brown and black with white underbellies and collar as well as dark tan legs. They have characteristic dark patches on the sides of their neck, and on top of the chest. Adult males can be distinguished from females by their black crown, dark ear coverts and fore-neck patch. When females also present with the black crown, basic male and female plumage is indistinguishable. Juveniles have consistent mottling of light and dark tans to match the sand nests. The breeding season is the easiest time to tell males and females apart, males have a rust-coloured cap at the beginning of the season. [6]
Western snowy plovers are migratory birds but are also year-round residents in the southern locations. Their breeding and nesting range includes the western coast of the United States; Washington and Northern Utah to southern California, wintering in Baja California, Mexico. [3]
Nesting sites are found on sandy beaches of open ocean shores and barren shores of non-tidal salt flat lakes as well as alkaline lakes in the interior or western United States. [7] Western snowy plovers need open plains to feed on invertebrates and see predators. Sand is important for nest building, nests are made in shallow depressions of sand called nest scrapes with sparse vegetation to better hide their eggs. [8] Too much vegetation can be an issue; American beachgrass from the east coast and European beachgrass are invasive species that were originally transplanted to stabilize sand dunes. [9] Now, the invasive grasses have replaced much of the native vegetation and taken up dune habitat of the western snowy plover. [10]
Western snowy plovers are known to run. They run to catch food or run and crouch when threatened. They fly when necessary for migration or threatened by attacks from predators like raptors, ravens or crows. Males are known to be aggressive and will charge at other males and birds. Plovers are territorial, when broods are too close, adults will fight other parents and peck chicks of other plovers that approach. [8]
Western snowy plovers congregate in flocks of fewer than 300 and practice preening, scratching, stretching and bathing in shallow water. They can be seen standing on one leg when cold, and periodically sleeping when roosting. [11]
Western snowy plovers use calls like "churr" to signal their chicks that danger is near, the chicks will flatten themselves against the sand to hide. [8] Chicks will "peep" until they are ready to fly. Other typical calls are variations of "tu-wheet", females are usually quieter and sound hoarse. During breeding season, "purrt" or "churr" can be heard to defend their nest. Outside the breeding period, many "ti" calls are sounded if disturbed. [6]
Western snowy plovers are active foragers and visual predators. Their diet includes invertebrates, insects and crustaceans. Typical prey items are juvenile mole crabs, brine fly larvae, beetles, flies, snails, clams, polychaete worms, and amphipods. [12] Plovers use the "stop and run" method to spot prey and capture it. Another method is to open their mouths and run at swarms of kelp and wrack flies, snapping their beaks. [13] During winter, plovers build up their fat reserves to prepare for migration north for the breeding season.
Western snowy plovers have two broods of 2-6 eggs measuring 2.8-3.4 cm by 2.1-2.4 cm, per year. Plovers will produce a third brood if the breeding season is longer due to late warm weather. Typical nesting season is March to September, peak nesting time is mid-April to August. [11] Nests are made by the male as a part of the courtship ritual, the male will dig a shallow depression in the sand, then line the pit with stones and shell pieces to prevent the eggs from overheating. Eggs have a 26-33 day incubation period, females attend the brood during the day and males at night. Eggs are well camouflaged with a speckled, sandy colouration. [14]
Once hatched, plover chicks are well-developed, precocial and cared for by the male parent, as the females will leave their first brood to breed with other males. [7] Within days of hatching, the chicks can run, forage, swim and leave the nest as soon as their down feather coat dries.
During the early days of western plover chick's lives, when a predator is near, the attending parent will perform a distraction display the "broken-wing" display, acting injured to lure the threat away from their young. Alternatively, the parent will fly flapping vigorously or run erratically to divert the attention of the predator. [8]
Effective April 5, 1993, the Pacific coast population of the western snowy plover is listed as threatened under the Endangered Species Act of 1973. [15] [16] From July 19, 2012, habitat along the California, Oregon, and Washington coasts is listed as critical for the survival of the Pacific distinct population segment. [15] [17]
Predation, urban development, introduction of beachgrass and nonnative species contribute to the degradation of western snowy plover nesting area and population. Common Ravens are known nest predators of the western snowy plover. Recent human activity provided ravens with more food, increasing their population density in the western United States, which threatens the plover population. [18] Other predators include harrier, gull, coyote, fox, feral cat and skunk. [8]
The killdeer is a large plover found in the Americas. It gets its name from its shrill, two-syllable call, which is often heard. It was described and given its current scientific name in 1758 by Carl Linnaeus in the 10th edition of his Systema Naturae. Three subspecies are described. Its upperparts are mostly brown with rufous fringes, the head has patches of white and black, and two black bands cross the breast. The belly and the rest of the breast are white. The nominate subspecies breeds from southeastern Alaska and southern Canada to Mexico. It is seen year-round in the southern half of its breeding range; the subspecies C. v. ternominatus is resident in the West Indies, and C. v. peruvianus inhabits Peru and surrounding South American countries throughout the year. North American breeders winter from their resident range south to Central America, the West Indies, and the northernmost portions of South America. Despite their name, they are not known for killing deer.
The piping plover is a small sand-colored, sparrow-sized shorebird that nests and feeds along coastal sand and gravel beaches in North America. The adult has yellow-orange-red legs, a black band across the forehead from eye to eye, and a black stripe running along the breast line. This chest band is usually thicker in males during the breeding season, and it is the only reliable way to tell the sexes apart. The bird is difficult to see when it is standing still, as it blends well with open, sandy beach habitats. It typically runs in short, quick spurts and then stops.
The snowy plover is a small shorebird found in the Americas. It is a member of the bird family Charadriidae, which includes the plovers, dotterels, and lapwings. The snowy plover was originally described by John Cassin in 1858, but was classified as a subspecies of the Kentish plover in 1922. Since 2011, the snowy plover has been recognized as a distinct species based on genetic and anatomical differences from the Kentish plover. Two or three subspecies are recognized, distributed along the Pacific coast of North America, Ecuador, Peru, and Chile, in several inland areas of the US and Mexico, along the Gulf Coast, and on Caribbean islands. The coastal populations consist of both residential and migratory birds, whereas the inland populations are mostly migratory. It is one of the best studied endemic shorebirds of the Americas, and one of the rarest.
The Eurasian dotterel, also known in Europe as just dotterel, is a small wader in the plover family of birds. It is the only species placed in the genus Eudromias.
The greater sand plover is a small wader in the plover family of birds. The spelling is often given as "greater sandplover" or "greater sand-plover", but the official IOC and British Ornithologists' Union spelling is "Greater Sand Plover". The specific leschenaultii commemorates the French botanist Jean Baptiste Leschenault de la Tour. Like most other species in the genus Anarhynchus, it was until recently included in the genus Charadrius.
The Siberian sand plover is a small wader in the plover family of birds. The International Ornithologists' Union split the Tibetan sand plover from the lesser sand plover and changed its vernacular name to Siberian sand plover. The specific mongolus is Latin and refers to Mongolia, which at the time of naming referred to a larger area than the present country.
The Caspian plover is a wader in the plover family of birds. The specific asiaticus is Latin and means "Asian", although in binomials it usually means the type locality was India.
Kittlitz's plover is a small shorebird in the family Charadriidae that breeds near coastal and inland saltmarshes, sandy or muddy riverbanks or alkaline grasslands with short vegetation. It is native to much of Sub-Saharan Africa, the Nile Delta and Madagascar. It is thought to be mainly polygamous and has monomorphic plumage.
The mountain plover is a medium-sized ground bird in the plover family (Charadriidae). It is misnamed, as it lives on level land. Unlike most plovers, it is usually not found near bodies of water or even on wet soil; it prefers dry habitat with short grass and bare ground. Its height is in the range of 5-9 inches, and length in the range of 8-10 inches ; and it weighs around 102 grams.
The collared plover is a small shorebird in the plover family, Charadriidae. It lives along coasts and riverbanks of the tropical to temperate Americas, from central Mexico south to Chile and Argentina.
The double-banded plover, known as the banded dotterel or pohowera in New Zealand, is a species of bird in the plover family. Two subspecies are recognised: the nominate Charadrius bicinctus bicinctus, which breeds throughout New Zealand, including the Chatham Islands, and Charadrius bicinctus exilis, which breeds in New Zealand's subantarctic Auckland Islands.
The New Zealand dotterel is a species of shorebird found only in certain areas of New Zealand. It is also called the New Zealand plover or red-breasted plover, and its Māori names include tūturiwhatu, pukunui, and kūkuruatu.
The fairy tern is a small tern which is native to the southwestern Pacific. It is listed as "Vulnerable" by the IUCN and the New Zealand subspecies is "Critically Endangered". Fairy terns live in colonies along the coastlines and estuaries of Australia, New Zealand, and New Caledonia, feeding largely on small, epipelagic schooling fishes, breeding in areas close to their feeding sites. They have a monogamous mating system, forming breeding pairs in which they mate, nest, and care for offspring.
The Malaysian plover is a small wader that nests on beaches and salt flats in Southeast Asia.
The white-fronted plover or white-fronted sandplover is a small shorebird of the family Charadriidae that inhabits sandy beaches, dunes, mudflats and the shores of rivers and lakes in sub-saharan Africa and Madagascar. It nests in small shallow scrapes in the ground and lays clutches of one to three eggs. The species is monogamous and long-lived, with a life expectancy of approximately 12 years. The vast majority of pairs that mate together stay together during the following years of breeding and retain the same territory. The white-fronted plover has a similar appearance to the Kentish plover, with a white fore crown and dark bands connecting the eyes to the bill.
The wrybill or ngutuparore is a species of plover endemic to New Zealand. It is the only species of bird in the world with a beak that is bent sideways in one direction, always to the right. A 2015 study found it to be within the Charadrius clade, with other New Zealand plovers its closest relatives; the nearest being the New Zealand dotterel or New Zealand plover, and then the double-banded plover or banded dotterel.
The Kentish plover is a small wader of the family Charadriidae that breeds on the shores of saline lakes, lagoons, and coasts, populating sand dunes, marshes, semi-arid desert, and tundra. Both male and female birds have pale plumages with a white underside, grey/brown back, dark legs and a dark bill; however, additionally the male birds also exhibit very dark incomplete breast bands, and dark markings either side of their head, therefore the Kentish plover is regarded as sexually dimorphic.
The long-billed plover is a species of wading bird in the family Charadriidae. It can be found in Bangladesh, Bhutan, Brunei, Cambodia, China, Hong Kong, India, Indonesia, Japan, Laos, Malaysia, Mongolia, Myanmar, Nepal, North Korea, Russia, South Korea, Sri Lanka, Taiwan, Thailand, and Vietnam. The long-billed plover is a migratory bird, so it breeds and spends the winter in different parts of its range. This bird can often be spotted along the shores of rivers, streams, in wetlands, and rice fields. It forages on the shoreline primarily for aquatic insects, insect larvae, and other invertebrates. It is difficult to distinguish between male and female individuals because of their similar plumage. The breeding season starts at the end of February or early March and ends in July. A male and a female forms a monogamous pair and maintains their territory throughout the breeding season. A global population survey in 2016 assessed the long-billed plover as a species of least concern on the International Union for Conservation of Nature (IUCN) Red List.
The Madagascar plover, also known as the black-banded plover, is a small monogamous shorebird in the family Charadriidae, native to western Madagascar. It inhabits shores of lagoons, coastal grasslands, and breeds in salt marshes. These plovers mainly nest in open grassland and dry mudflats surrounding alkaline lakes. The species is classified as vulnerable by the IUCN because of its low breeding success, slow reproductive rate, and weak adaptation to increasing habitat loss, leading to declining population numbers.
Moss Landing Wildlife Area is a California State wildlife preserve on the shore of Elkhorn Slough.