Double-banded plover | |
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Breeding plumage | |
Non-breeding plumage | |
Scientific classification | |
Domain: | Eukaryota |
Kingdom: | Animalia |
Phylum: | Chordata |
Class: | Aves |
Order: | Charadriiformes |
Family: | Charadriidae |
Genus: | Anarhynchus |
Species: | A. bicinctus |
Binomial name | |
Anarhynchus bicinctus | |
Synonyms | |
Charadrius bicinctus (protonym) |
The double-banded plover (Anarhynchus bicinctus), 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, [2] which breeds throughout New Zealand, including the Chatham Islands, and Charadrius bicinctus exilis, [3] which breeds in New Zealand's subantarctic Auckland Islands.
A 2015 study found its closest relatives to be two other plovers found in New Zealand, the New Zealand dotterel (Anarhynchus obscurus, also called the New Zealand plover) and the wrybill (Anarhynchus frontalis, which the study found to be in the Charadrius clade). [4]
The double-banded plover is distinguished by a dark, grey-brown back with a distinctive white chest and a thin band of black situated just below the neck running across the chest along with a larger brown band underneath. [5] During breeding season, these bands are more dominantly shown on the males compared to females. [2] Younger birds have no bands, and are often speckled brown on top, with less white parts. These shorebirds have relatively long legs to allow them to easily wade around shallow waters and move efficiently around sandy beaches. Their long pointed wings aid in traveling long distances as they allow the bird to be very agile. [6] The double-banded plover's head is prominent with large, dark-brown eyes and a sturdy black bill. Due to similar colors within the plovers ideal habitat, spotting these birds can be difficult to achieve, however the "chirp-chirp" call is easily heard and their habit of running quickly then pausing to feed on food can catch the eye of observers.
Distribution of the banded dotterel varies seasonally. They are at their breeding grounds, which are entirely in New Zealand, from roughly August to November. Many move to coastal locations in New Zealand in the immediate post-breeding season (roughly December to March). A large proportion of the population migrates to Australia in autumn and winter (roughly April to July). [6]
Banded dotterels breed throughout much of the North and South Islands and their offshore islands, plus Stewart Island, the Chatham Islands and the Auckland Islands. [7] The largest number nest on the braided riverbeds of Marlborough, Canterbury, Otago and Southland in the South Island. Many others breed on shingle riverbeds in Hawke's Bay, the Manawatu and the Wairarapa in the North Island. [8] [9] Some nest on sandy coasts, especially near the mouths of streams or rivers in the North and South islands. [9] Small numbers breed in higher altitude areas such as Tongariro National Park and subalpine areas of Central Otago. [8]
In the summer months of December to March the birds disperse somewhat from their breeding grounds, with many that nest in inland locations moving to estuaries and other coastal wetlands. In autumn and winter many move further, with most that nest in the riverbeds and outwash fans of the South Island high country migrating 1,600 kilometres or more to south-eastern Australia, including Tasmania, remaining there until mid-winter. [7] This more or less west–east flight is uncommon for migratory birds and unique among migratory wading birds, [6] which usually fly on a north–south axis. Birds that breed in the South Island lowlands, the northern South Island and the southern two-thirds of the North Island mostly stay on the New Zealand coast, throughout the country, with some moving to harbours and estuaries in the northern North Island. [7] [8] Dotterels that nest near coastal wintering grounds may move only a few kilometres. [7] Populations in the Chatham and Auckland Islands generally move only locally throughout the year, although a few from Auckland Island venture to Campbell Island. [7] Vagrant birds reach New Caledonia, Vanuatu and Fiji. [7]
Northern populations of banded dotterel commonly inhabit sandy beaches and sandpits, as well as a few pairs accustoming to shell banks in harbours, with a few found on gravel beaches, with nesting sites generally clustered around stream-mouths. [8] In the breeding period, males construct numerous nests on open patches of slightly elevated sand or on shells and occasionally in cushion plants which are all mostly padded with various materials retrieved from close by. [10] Birds in the southern parts of New Zealand, such as Stewart Island, prefer to breed on unprotected subalpine and stony areas, but become coastal during off-breeding months where they feed around the beach areas.
Banded dotterels start returning to North Island breeding areas in June–July and to inland Canterbury areas in August–September. [9] They form seasonal monogamous pairs where once a partner is found, they remain with that one bird for the rest of the breeding season to help raise the young. [11] [ failed verification ] During this time, the male grows colored bands on his chest prior to the beginning of the breeding season and later females are attracted by the loud calls of the male where they are then presented with several nests which they can choose between while the male puts on a defensive display, protecting his territory, where it flies towards any possible intruder in a fast butterfly-like circular motion flight. [11] [ failed verification ] This species usually constructs nests upon slightly elevated, open patches on the sand, shells or sometimes hollows in cushion plants or between rocks which are broadly padded with various materials such as tussock tillers, smaller stones and shells, grass, lichen, moss, twigs etc. [12] [ failed verification ]
There can be several hundred birds in one area during this season. From August to September, the dotterels lay two to four eggs and can re-lay up to three times if there is a failure or predation. Incubation of these eggs generally takes 28–30 days where the young fledging period extends to around six weeks. [11] [ failed verification ]
Chicks leave their nest within a day of hatching and accompany their parents in the hunt for food. [13] At the slimmest indication of potential danger, watchful adult birds sound the alarm causing the chicks to run a few feet in a scattered motion then squat with their legs doubled over beneath them and their head stretched out firmly against the ground in front of them, camouflaging into the coastal terrain around them. [14] They remain stationed without moving until the parents decide the surrounding environment is clear and safe to move again. Unlike the young of most bird species, these chicks will be reliant to feed themselves with parents guarding close by for five to six weeks until they fledge. The parents will then stay close by for several days until the chicks join flocks and become fully independent. [14]
Both of the parents continue to tend their young for another two weeks when birds have grown their contour feathers and the birds all part ways. Some of these birds migrate to southern Australia. [7] Other dotterels fly to the northern areas of New Zealand in groups alongside many other adults and newly fledged chicks. A high percentage of offspring return to the breeding grounds for mating within their first year, with the rest of the generation returning in their second year. [12] [ failed verification ]
Double-banded plovers are predominantly opportunistic carnivores, feeding on aquatic invertebrates and other insects along coastlines or rivers. They have been known to also consume berries off nearby shrubs such as Coprosma and Muehlenbeckia . [15]
The birds forage both in daytime and at night, using different techniques for each. [16] During the day, plovers were seen spending greater amounts of time flying and more time standing alert and watchful. The birds were observed to walk, peck, run, forage, and groom both day and night, however during the day the number of paces walked was much greater than movement at night as the birds would spot insect movement and move at a fast pace to the area to peck before moving off again. [16]
During the night, double-banded plovers were noted to have a repeated pecking techniques and spent a lot more time waiting in one area, suggesting that they were trying to use the nearby vicinity to catch prey in, due to the fact that prey detection distances would have been significantly reduced in lack of light. [17] This reduction of paces during the night causes prey to find it more difficult to detect the stilled birds, which increases the ability of the plovers to detect their prey and decreases the chance that prey could be unnoticed.
Birds located on breeding grounds were commonly found to have a more varied diet containing insect larvae, spiders, beetles, aquatic insects such as caddisflies, stoneflies and mayflies along with terrestrial flies. [18] The contents of various fecal samples from plovers included flies, adult beetles and bugs. Birds on Canterbury riverbeds consume large amounts of fruits of Coprosma petrei and Mueblenbeckia axillaris . [15]
As a ground-nesting bird, many dangers arise through predation by mammalian predators that were introduced to New Zealand, human impacts that can cause habitat loss and various parasites that can target these birds.
A study of nesting sites in braided rivers in the Mackenzie Basin in the 1990s found that predation, mainly of eggs, occurred at about half the nests. Feral cats were the most common predator of eggs there, followed by hedgehogs and ferrets, and to much lesser extent, stoats. Cats also killed adult birds and chicks. [19] [20] Cats, ferrets and stoats prey on rabbits too and when high rabbit numbers are reduced by human control or disease, predation of dotterel nests increases due to prey switching. [20]
Other animals such as farm stock and uncontrolled dogs moving through nesting areas pose a threat to the nesting birds by crushing eggs and disturbing nesting birds. [19]
Feather mites (Brephosceles constrictus) can pose a threat to the health of these birds as they feed predominantly on the blood of the bird along with feathers, skin or scales taking up to two hours. This can lead to increased levels of stress resulting in anemia, decreased egg production and in some cases, death.
Prior to 1908, banded dotterels in New Zealand were shot in large numbers by market gunners upon the return of migrating birds for breeding. In 1908, the species was placed on the protected list, prohibiting further shooting, to the point where they are now moderately common. [13]
In 2013 local Maori in the Pencarrow Coast, Wellington region, placed a rahui on the area, to protect 20 pairs of banded dotterel from dogs and cars. [21] This species has the conservation status of "Regionally Vulnerable" in the Wellington region. [22] The species is classified as Near Threatened. [1]
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.
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.
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 white-fronted tern, also known as tara, sea swallow, black-billed tern, kahawai bird, southern tern, or swallow tail, was first described by Johann Friedrich Gmelin in 1789. A medium-sized tern with an all-white body including underwing and forked tail, with grey hues on the over the upper side of the wing. In breeding adults a striking black cap covers the head from forehead to nape, leaving a small white strip above the black bill.
The black stilt or kakī (Māori) is a wading bird found in New Zealand. It is one of the world's rarest birds, with 169 adults surviving in the wild as of May 2020. Adult kakī have distinctive black plumage, long pink legs, and a long thin black bill. Black stilts largely breed in the Mackenzie Basin in the South Island, and are threatened by introduced feral cats, ferrets, and hedgehogs as well as habitat degradation from hydroelectric dams, agriculture, and invasive weeds.
The New Zealand plover is a species of shorebird found only in certain areas of New Zealand. It is also called the New Zealand dotterel or red-breasted dotterel, and its Māori names include tūturiwhatu, pukunui, and kūkuruatu.
The New Zealand fairy tern or tara-iti is a subspecies of the fairy tern endemic to New Zealand. It is New Zealand's rarest native breeding bird, with about 40 individuals left in the wild. It nests at four coastal locations between Whangarei and Auckland in the North Island. It is threatened by introduced predators, extreme storms and tides, beach activity, and waterfront development.
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 red-capped plover, also known as the red-capped dotterel, is a small species of plover.
The oriental plover, also known as the oriental dotterel, is a medium-sized plover closely related to the Caspian plover. It breeds in parts of Mongolia and China, migrating southwards each year to spend its non-breeding season in Indonesia, New Guinea and northern Australia.
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.
The northern New Zealand dotterel or northern red-breasted plover is a shorebird which breeds exclusively on beaches in New Zealand's North Island.
The southern New Zealand dotterel or southern red-breasted plover is a critically endangered subspecies of the New Zealand dotterel, a shorebird endemic to New Zealand. The subspecies was once widespread across the South Island, but now breeds almost exclusively on Stewart Island.
Ailsa Diane McGilvary is a New Zealand bird conservationist, and photographer.