Northern Pintail Duck

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The Pintail or Northern Pintail (Anas acuta) is a widely occurring duck  which breeds in the northern areas of  Europe,  Asia  and  North America. It is strongly migratory  and winters south of its breeding range to the  equator. Unusually for a bird with such a large range, it has no geographical subspecies if the possibly con-specific Eaton's Pintail  is considered to be a separate species.

This is a fairly large duck, with a long pointed tail that gives rise to the species' English and scientific names. The Northern Pintail's many names describe the male's two long black tail feathers, which in flight look like a single pin or twig (thus, the nickname sprig). These feathers are very distinctive, accounting for a quarter of the total length of the drake when in full plumage.| [2] Fast and graceful fliers, pintails are equipped with long wings, small heads, and long necks that seem built for streamlined aerodynamics. Both sexes have blue gray bills and gray legs and feet. The drake is more striking, having a thin white stripe running from the back of its chocolate-colored head down its neck to its mostly white undercarriage. The drake also has attractive gray, brown, and black patterning on its back and sides. The hen's plumage is more subtle and subdued, with drab brown feathers similar to those of other female dabblers. Hens make a coarse quack and the drakes a flute-like whistle.| [2]

The Northern Pintail is a bird of open wetlands  which nests on the ground, often some distance from water. It feeds by dabbling for plant food and adds small invertebrates  to its diet during the  nesting season. It is highly gregarious when not breeding, forming large mixed flocks with other species of duck.

This duck's population is affected by predators, parasites and avian diseases. Human activities, such as agriculture, hunting and fishing, have also had a significant impact on numbers. Nevertheless, this species' huge range and large population mean that it is not threatened globally.

Taxonomy

This species was first described by Linnaeus  in his Systema naturae in 1758 as Anas acuta| [3]  The scientific name comes from two  Latin  words: anas, meaning "duck", and acuta, which comes from the verb acuere, which means "sharpen"; the species term, like the  English  name, refers to the pointed tail of the male.| [4]

Within the large dabbling duck  genus Anas,| [3]  the Northern Pintail's closest relatives are other pintails, such as the  Yellow-billed Pintail  (A. georgica) and  Eaton's Pintail  (A. eatoni). The pintails are sometimes separated in the genus Dafila (described by Stephens, 1824), an arrangement supported by morphological, molecular and behavioural data.| [5]  | [6]  | [7]  The famous  British   ornithologist  Sir  Peter Scott  gave this name to his daughter, the artist Dafila Scott.| [8]

Eaton's Pintail has two subspecies, A. e. eatoni (the Kerguelen Pintail) of Kerguelen Islands, and A. e. drygalskyi (the Crozet Pintail) of  Crozet Islands , and was formerly considered conspecific with the  northern hemisphere's  Northern Pintail. Sexual dimorphism is much less marked in the southern pintails, with the male's breeding appearance being similar to the female plumage. Unusually for a species with such a large range, Northern Pintail has no geographical subspecies if Eaton's Pintail is treated as a separate species.| [9]

Description
EnlargeMale in British Columbia, CanadaThe Northern Pintail is a fairly large duck with a wingspan of 23.6–28.2 centimetres (9.3–11.1 in). The male is 59–76 centimetres (23–30 in) in length and weighs 450–1360 grammes (1–3 lb), and therefore is considerably larger than the female, which is 51–64 centimetres (20–25 in) long and weighs 454–1135 grammes (1–2.5 lb).| [10] The male in breeding  plumage  has a chocolate-brown head and white breast with a white stripe extending up the side of the neck. Its upperparts and sides are grey, but elongated grey feathers with black central stripes are draped across the back from the shoulder area. The vent area is yellow, contrasting with the black underside of the tail,| [9] which has the central feathers elongated to as much as 10 centimetres (4 in). The bill is bluish and the legs are blue-grey.| [11]

The adult female is mainly scalloped and mottled in light brown with a more uniformly grey-brown head, and its pointed tail is shorter than the male’s; it is still easily identified by its shape, long neck, and long grey bill.

In non-breeding (eclipse) plumage, the drake Pintail looks similar to the female, but retains the male upperwing pattern and long grey shoulder feathers. Juvenile birds resemble the female, but are less neatly scalloped and have a duller brown speculum  with a narrower trailing edge.| [12]

The Pintail walks well on land, and swims buoyantly.| [9] It has a very fast flight, with its wings slightly swept-back, rather than straight out from the body like other ducks. In flight, the male shows a black speculum bordered white at the rear and pale rufous at the front, whereas the female's speculum is dark brown bordered with white, narrowly at the front edge but very prominently at the rear, being visible at a distance of 1600 metres (1 mi).| [12]

The male's call is a soft proop-proop whistle, similar to that of the Common Teal, whereas the female has a  Mallard-like  descending quack, and a low croak when flushed.<sup class="reference" id="cite_ref-Madge_8-3">| [9]

Distribution and habitat
EnlargeNon-breeding males wintering in IndiaThe Northern Pintail has been called the "nomads of the skies." due to their wide-ranging migrations.<sup class="reference" id="cite_ref-du_1-2">| [2] This  dabbling duck  breeds across northern areas of  Eurasia  south to about  Poland  and  Mongolia ,<sup class="reference" id="cite_ref-umich_9-1">| [10]  and in  Canada,  Alaska  and the  Midwestern United States. It winters mainly south of its breeding range, reaching almost to the equator in Panama, northern  sub-Saharan Africa  and tropical  South Asia. Small numbers migrate to Pacific  islands, particularly  Hawaii, where a few hundred birds winter on the main islands in shallow  wetlands  and flooded agricultural habitats.<sup class="reference" id="cite_ref-Madge_8-4">| [9]   Transoceanic  journeys also occur: a bird that was caught and  ringed  in  Labrador , Canada, was shot by a hunter in England nine days later,<sup class="reference" id="cite_ref-umich_9-2">| [10]  and  Japanese-ringed  birds have been recovered from six US states east to  Utah  and  Mississippi .<sup class="reference" id="cite_ref-ESPN_12-0">| [13]  In parts of the range, such as  Great Britain  and the northwestern United States, the Pintail may be present all year.<sup class="reference" id="cite_ref-Collins_11-2">| [12]  <sup class="reference" id="cite_ref-Cornell_13-0">| [14]  <sup class="reference" id="cite_ref-SDB_14-0">| [15]

The Northern Pintail's breeding habitat is open unwooded wetlands, such as wet grassland, lakesides or tundra. In winter, it will utilise a wider range of open habitats, such as sheltered estuaries, brackish marshes and coastal lagoons. It is highly gregarious outside the breeding season and forms very large mixed flocks with other ducks.<sup class="reference" id="cite_ref-Madge_8-5">| [9]

Breeding
EnlargeBreeding pairBoth sexes reach sexual maturity at one year of age. The male mates with the female by swimming close to her with his head lowered and tail raised, continually whistling. If there is a group of males, they will chase the female in flight until only one drake is left. The female prepares for copulation, which takes place in the water, by lowering her body; the male then bobs his head up and down and mounts the female, taking the feathers on the back of her head in his mouth. After mating, he raises his head and back and whistles.<sup class="reference" id="cite_ref-umich_9-3">| [10]

Breeding takes place between April and June, with the nest being constructed on the ground and hidden amongst vegetation in a dry location, often some distance from water. It is a shallow scrape on the ground lined with plant material and down.<sup class="reference" id="cite_ref-Madge_8-6">| [9] The female lays seven to nine cream-coloured eggs at the rate of one per day;<sup class="reference" id="cite_ref-umich_9-4">| [10]  the eggs are 55 x 38 millimetres (2.2 x 1.5 in) in size and weigh 45 grammes (1.6 oz), of which 7% is shell.<sup class="reference" id="cite_ref-BTO_15-0">| [16]  If predators destroy the first clutch, the female can produce a replacement clutch as late as the end of July.<sup class="reference" id="cite_ref-umich_9-5">| [10]

The hen alone incubates the eggs for 22 to 24 days before they hatch. The precocial  downy chicks are then led by the female to the nearest body of water, where they feed on dead insects on the water surface. The chicks fledge in 46 to 47 days after hatching, but stay with the female until she has completed moulting .<sup class="reference" id="cite_ref-umich_9-6">| [10]

Around three-quarters of chicks live long enough to fledge, but not more than half of those survive long enough to reproduce.<sup class="reference" id="cite_ref-umich_9-7">| [10] The maximum recorded age is 27 years and 5 months for a  Dutch  bird,<sup class="reference" id="cite_ref-BTO_15-1">| [16]  but the average life span for wild birds will be much shorter than this, and is likely to be similar to that of other wild ducks, such as the  Mallard, at about two years.<sup class="reference" id="cite_ref-Guidetobirds_16-0">| [17]

edit ] Feeding
EnlargeUp-ending to feed (male on right)The Pintail feeds by dabbling and upending in shallow water for plant food mainly in the evening or at night, and therefore spends much of the day resting.<sup class="reference" id="cite_ref-Madge_8-7">| [9] Its long neck enables it to take food items from the bottom of water bodies up to 30 centimetres (1 ft) deep, which are beyond the reach of other dabbling ducks like the Mallard.<sup class="reference" id="cite_ref-Gooders_10-1">| [11]

The winter diet is mainly plant material including seeds and rhizomes  of aquatic plants, but the Pintail sometimes feeds on roots, grain and other seeds in fields, though less frequently than other Anas ducks.<sup class="reference" id="cite_ref-Gooders_10-2">| [11]  During the nesting season, this bird eats mainly  invertebrate  animals, including aquatic  insects,  molluscs  and  crustaceans .<sup class="reference" id="cite_ref-umich_9-8">| [10]

Health
EnlargeMale preeningPintail nests and chicks are vulnerable to predation by mammals, such as foxes  and  badgers, and birds like  gulls ,  crows  and  magpies. The adults can take flight to escape terrestrial predators, but nesting females in particular may be surprised by large carnivores  such as  bobcats .<sup class="reference" id="cite_ref-umich_9-9">| [10]  Large  birds of prey, such as  Northern Goshawks , will take ducks from the ground, and some  falcons , including the  Gyrfalcon , have the speed and power to catch flying birds.<sup class="reference" id="cite_ref-Forsman_17-0">| [18]

It is susceptible to a range of parasites  including  Cryptosporidium ,  Giardia ,  tapeworms, blood parasites and external feather lice,<sup class="reference" id="cite_ref-AEM_18-0">| [19]  <sup class="reference" id="cite_ref-tape_19-0">| [20]  <sup class="reference" id="cite_ref-Williams_20-0">| [21]  <sup class="reference" id="cite_ref-lice_21-0">| [22]  and is also affected by other avian diseases. It is often the dominant species in major mortality events from avian botulism  and avian  cholera ,<sup class="reference" id="cite_ref-Friend_22-0">| [23]  and can also contract  avian influenza, the  H5N1  strain of which is highly pathogenic and occasionally infects humans.<sup class="reference" id="cite_ref-USDA_23-0">| [24]

The Northern Pintail is a popular species for game shooting because of its speed, agility, and excellent eating qualities, and is hunted across its range.<sup class="reference" id="cite_ref-Marrone_24-0">| [25] <sup class="reference" id="cite_ref-Cocker_25-0">| [26]  Although one of the world's most numerous ducks,<sup class="reference" id="cite_ref-BTO_15-2">| [16]  the combination of hunting with other factors has led to population declines, and local restrictions on hunting have been introduced at times to help conserve numbers.<sup class="reference" id="cite_ref-USFWSnews_26-0">| [27]

This species' preferred habitat of shallow water is naturally susceptible to problems such as drought or the encroachment of vegetation, but this duck’s habitat might be increasingly threatened by climate change.<sup class="reference" id="cite_ref-BTO_15-3">| [16] Populations are also affected by the conversion of wetlands and grassland to arable crops, depriving the duck of feeding and nesting areas. Spring planting means that many nests of this early breeding duck are destroyed by farming activities,<sup class="reference" id="cite_ref-Audubon_27-0">| [28] and a Canadian study showed that more than half of the surveyed nests were destroyed by agricultural work such as ploughing and  harrowing .<sup class="reference" id="cite_ref-usdafs_28-0">| [29] |   FemaleHunting with lead shot, along with the use of lead sinkers in  angling, has been identified as a major cause of  lead poisoning  in waterfowl, which often feed off the bottom of lakes and wetlands where the shot collects.<sup class="reference" id="cite_ref-Scheuhammer_29-0">| [30]  A  Spanish  study showed that Northern Pintail and  Common Pochard  were the species with the highest levels of lead shot ingestion, higher than in northern countries of the western Palearctic flyway, where lead shot has been banned.<sup class="reference" id="cite_ref-Mateo_30-0">| [31]  In the United States, Canada, and many western European countries, all shot used for  waterfowl  must now be non-toxic, and therefore may not contain any  lead .<sup class="reference" id="cite_ref-USFWS2_31-0">| [32]  <sup class="reference" id="cite_ref-Newsc_32-0">| [33]  <sup class="reference" id="cite_ref-BASC_33-0">| [34]

Status
The Northern Pintail has a large range, estimated at 28.4 million square kilometres (11 million sq mi), and a population estimated at 5.3–5.4 million individuals.<sup class="reference" id="cite_ref-BirdLife_34-0">| [35] It is therefore not believed to meet the IUCN Red List threshold criterion of a population decline of more than 30% in ten years or three generations, and is evaluated as Least Concern.

In the Palaearctic, breeding populations are declining in much of the range, including its stronghold in  Russia , and are otherwise stable or fluctuating.<sup class="reference" id="cite_ref-BWP_35-0">| [36]

Pintails in North America at least have been badly affected by avian diseases, with the breeding population falling from more than 10 million in 1957 to 3.5 million by 1964. Although the species has recovered from that low point, the breeding population in 1999 was 30% below the long-term average, despite years of major efforts focused on restoring the species. In 1997, an estimated 1.5 million water birds, the majority being Northern Pintails, died from avian botulism during two outbreaks in Canada and Utah.<sup class="reference" id="cite_ref-Friend_22-1">| [23]

The Northern Pintail is one of the species to which the Agreement on the Conservation of African-Eurasian Migratory Waterbirds ( AEWA ) applies,<sup class="reference" id="cite_ref-AEWA_36-0">| [37] but it has no special status under the Convention on International Trade in Endangered Species of Wild Fauna and Flora ( CITES ), which regulates international trade in specimens of wild animals and plants.<sup class="reference" id="cite_ref-umich_9-10">| [10]

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