Pair of pintail ducks ( Anas acuta )
|Linnaeus , 1758|
The pintail ( Anas acuta ) is a species from the family of the duck birds (Anatidae), which is widespread in northern Eurasia and North America. In Central Europe, this species only breeds irregularly and relatively rarely. It is mostly migrant and winter visitor and stays from September to April mainly in the lowlands and in the coastal regions.
The pintail is slightly smaller than a mallard . The drake has a long and pointed tail in its splendid dress , which has led to the name pintail. The female has a light brown plumage all year round, with the individual feathers of the cover plumage being broadly lined with gray.
Pintails are breeding birds in the open lowlands, which have larger, standing inland waters and floodplains. The nest is built on the ground and is often some distance from open water. Pintail feed mainly on aquatic plants, they green delnd record. Outside the breeding season, pintail ducks often form large schools. In the Volga Delta these swarms occasionally consist of 150,000 to 300,000 individuals. The species is considered not endangered worldwide. In the Red List of Germany's breeding birds from 2015, the species is listed in Category 3 as endangered.
Body measurements and plumage of adult pintail ducks
The pintail looks very slender and has a noticeably long and thin neck. When fully grown, drakes reach a body length of 59 to 76 centimeters. Your body weight is in a range of 550 to 1300 grams and averages around 850 grams. The average wing length in males is about 27.5 centimeters. With a body length of 51 to 64 cm and a wing length of 26 cm, females are somewhat smaller and with an average body weight of 735 g (400–1200 g) also lighter than the males. Pintail ducks usually have their minimum weight in February of each year; the maximum weight is reached by drakes in October and by females in August.
In their splendid dress, the males are dark brown in color on the throat, front lower neck and sides of the head. The top of the head differs from the other head parts in that it is even darker in color. In the middle of the neck there is an almost black longitudinal band. The beak is blue-gray. A narrow white and clearly demarcated wedge extends on the back of the head to about the height of the beak. Due to this characteristic head markings, the pintail's drakes can be clearly distinguished from other duck species in the range.
The chest and lower half of the front neck are white. The large shoulder feathers are greatly elongated and have a wide, white-yellowish to light-brownish border. The flanks are narrowly banded in dark gray and white, the underside of the body is white. In front of the sharply defined, black under-tail-coverts there is a yellowish-white to light-brownish feather area. The long and pointed tail feathers have a length of up to ten centimeters. The central control springs are black; those adjoining the central control springs have a black outer flag, while the inner flags are gray-brown with light-brownish edges. The external control springs are dark on the outside and light brown-gray on the inside. When resting, the drake resembles the female. Individual drakes have single black-gray feathers with a coarse gray-brown and white transverse wave on the back, on the shoulders and on the rump. The middle control feathers are slightly elongated in the male, even when the male is resting. The change to the resting dress begins in the male around June. The change of color to the splendid dress begins in December and is usually completed in January to February.
Adult females have light brown plumage. The cover plumage is broadly lined with gray. As a result, they have a more pronounced shade of gray than the females of other species from the genus of actual ducks . Further distinguishing features are the long neck and the long, gray to bluish horn-colored bill, which is significantly narrower compared to the mallard. As with the male, the legs are gray to gray-blue in color. The webbed feet are blackish. The iris is brown in both sexes.
Appearance of young birds and chicks
Pintail ducks that are not yet fully grown resemble the female in their youthful dress. In their case, however, the ventral side is spotted, while adult females have an almost monochrome ventral plumage. The feathers on the upper side of the body have a narrower gray border in young birds. This makes young birds look a little darker overall than the adult females. Young drakes change into the magnificent dress for the first time in their first winter. Individual parts of the feathers on the upper side of the body and the outer control feathers remain unmodeled. The central control feathers do not yet reach the length that is characteristic of adult drakes.
The chicks of the pintail ducks resemble those of the mallards in their downy clothing. The top of the head and the back are olive brown. A light vertical stripe runs on both sides of the central back from the wings to the sides of the tail. The chicks' creamy brown face is streaked with dark lines in the eyes and cheeks. The underside of the body of the chicks is creamy white to pale brown. The beak is lead gray; the feet and legs are light gray to greenish gray. After the second week of life, the pattern of the downy dress becomes increasingly indistinct. Three-week pintail ducks already have easily recognizable feathers about 1.3 centimeters long on their shoulders, flanks and tail. At about six weeks old, the pintail ducks are fully feathered. Remains of the down feathers can still be found on the neck, back, rump and wings. The young ducks are able to fly at around seven weeks.
Pintails can run skillfully on land. They are relatively high in the water, so that most of the body and the tail are visible. The long control springs point slightly upwards in swimming males.
The flight of the pintail is very quick. In contrast to most other duck species, the wings are slightly bent backwards. Because of the slim body shape and the relatively long and narrow wings, ornithologist Janet Kear describes the flight of the pintail ducks as "almost like a gull". In the drake, the bronze-green and red-brown wing mirrors are very clearly visible in flight, with a brown band at their front end and a black and white band at their rear end. These wing mirrors are less easy to see in females. In addition to the elongated body shape, the clear field characteristics of flying pintail ducks also include the narrow, light rear edge of the wings and the thin neck. If pintail ducks fly high up from the water, they do not need a running phase, but start relatively steeply out of the water. When landing in the water, they stretch their feet far forward.
The voices of both sexes are not noticeable. In addition, females of the pintail rarely let their voice be heard. Their call is reminiscent of the croaking of the female mallard and, like this one, drops slightly in pitch. The scare call of frightened females is a croak that is dark in pitch . Courting or excited drakes of the pintail express a quiet, nasal wä-Glück-hä or krlük . The neck is first stretched and then pulled in again. These calls are similar to that of the teal . However, those of the pintail are a bit lower and more subdued in their pitch. Philistines who feel disturbed can also hear a faint and nasal sounding wrä wrä wrä ...
The pintail, widespread in the Holarctic , is the most northern brooding duck. Their breeding area, the distribution limits in Eurasia between the July isotherms of 6 and 23 ° C, in North America even up to 28 ° C, extends into the arctic tundra. It is the most common species of duck there. Up to 5 breeding pairs per square kilometer breed in suitable arctic habitats. In the Mackenzie Delta , which particularly meets the habitat requirements of the pintail ducks, up to 8.8 breeding pairs per square kilometer were counted.
The range of the pintail ducks extends over an area of about 10 million square kilometers and is therefore the largest of all duck birds . It stretches from the coastal regions of Iceland , the northern tip of Ireland and Great Britain over Eurasia to Canada , Alaska , the Midwest of the USA and the southwest of Greenland. In western Europe there are some advanced breeding sites, some of which are only sporadically occupied, in the Camargue , in southern Spain and in the Po Delta. About 90 percent of the European brood population breed on Russian territory. In contrast, pintail ducks are relatively rare breeding birds in Germany. The breeding population is estimated at around 300 pairs. Most breed in the North German Plain. There are also breeding occurrences in the Hungarian lowlands and subsequently also sporadically in eastern Austria.
In some regions of the distribution area the pintail is a resident bird . These include the UK and the Northwest US. The vast majority of pintail ducks overwinter in regions south of the breeding area. In relation to their wintering places, they show a high degree of loyalty to their location.
North American breeding birds overwinter for the most part south of the 40th parallel north. Their wintering area almost reaches the equator in Panama . A particularly high number of wintering pintail can be found in California as well as in the coastal region of Mexico and the US state of Louisiana . In Africa the wintering areas of Eurasian breeding birds extend as far as Tanzania , Nigeria , Mali and Senegal . In Asia, parts of the population also overwinter in tropical South Asia. Some of them move as far as Sri Lanka and Borneo . Odd guests also occasionally reach Micronesia , Polynesia and New Guinea . A pintail drake was observed northeast of Perth , Australia in July 1985 .
Not all pintail ducks migrate far south. In western Europe, the Atlantic coast of France as well as Great Britain and Ireland are important wintering quarters. There are also thousands of pintail ducks in the Netherlands in January. The Mediterranean area is also one of the wintering quarters. In winter, pintail ducks can be found here from southern Spain and Morocco to the Nile Delta. A small number of pintail ducks overwinter on Pacific islands. Hundreds of birds are found annually in Hawaii and spend the winter there on flooded lowlands.
A number of ringing finds indicate a large number of ocean crossings for pintail ducks, with Pacific crossings being more common than Atlantic crossings. The birds that overwinter in Hawaii breed in eastern Russia. Pintail ducks ringed in Japan have been found in the eastern United States. The flight performance of the pintail ducks is impressive. A pintail ringed in Labrador, Canada , was shot by a hunter in the UK nine days later. The ringing findings made it possible to prove that another pintail duck had covered 560 kilometers overnight.
Pintail ducks are basically breeding birds in open landscapes. They avoid forested regions. The activity area of a pair of pintail ducks covers about 500 hectares, with both intra- and interspecific overlaps in the activity area.
The habitat of the pintail ducks during the breeding season includes extensive moors, wet meadows, swamps, floodplain areas of larger rivers and lake areas, whereby they prefer silting and vegetation-rich waters. They are among the characteristic breeding birds of the arctic and sub-arctic tundra. The rearing time of their young falls there in the short summer period with a rich supply of insects and protein-rich plant food. In their southern breeding area, thinly forested steppes are also part of the breeding area, provided they have enough open water areas. Pintail ducks are habitat opportunists who quickly colonize suitable breeding grounds: Studies in the US state of North Dakota show that pintail ducks use ponds as breeding grounds that have been newly created for grazing cattle. Here, ponds between 0.4 and 0.8 hectares in size had the highest brood density.
During the moult, pintail ducks prefer small, exposed areas of water in the reed beds of nutrient-rich lakes. Pintail ducks are very sociable birds at this time. Large flocks of pintail ducks can be found on the great lakes of Kazakhstan and in the mouth of the Volga. Other moulting sites with mass collections of pintail ducks can also be found in the forest steppe and tundra zones of western Siberia, such as on the lower reaches of the Ob and the Yenisei . The drakes that do not take part in the breeding business and the females that have hatched unsuccessfully or not at all arrive at the moulting sites. The other females later join the fledglings as soon as they have moulted in the breeding area. Between 150,000 and 300,000 pintail ducks can then be found in this region in late summer. They also socialize with other duck species. The beginning of the migration to the winter quarters depends on the respective distribution region. It starts in Kazakhstan in mid-August. During the migration, they are also in the estuary, brackish water zones, lagoon and lagoon.
Way of life
Both sexes reach their fertility at the end of their first year of life. However, most of the females first breed towards the end of their second year of life. The pair formation begins already during the winter migration back to the breeding areas. Breeding pairs only come together for one breeding period.
The drake woos the female swimming on the water by approaching here with lowered head and raised tail feathers. In doing so, he lets out his courtship calls continuously. The mating takes place on the water. The female signals her willingness to mate by immersing her body deeper in the water. The male reacts to this with an agitated burping of the head, in which the head is stretched up while the beak is held horizontally, and finally mounts the female. During mating, the drake grabs the feathers at the back of the partner's head with its beak. After mating, the drake calls again with its head back.
Occasionally, so-called row flights can be observed in pintail ducks, in which two or more drakes fly behind a single female. In phases of pair formation that is still taking place, such straight flights occur when several drakes harass a female, the female is blown up and the males follow him. They can also be observed occasionally when an already mated drake defends the nesting area against another pair and follows the pair flying to the boundaries of the territory.
The breeding season is between April and June and begins immediately after the onset of frost in the breeding waters. The length of time between arrival in the breeding area and the start of breeding depends on the respective distribution region. At the southern border of the breeding area, it usually takes 35 to 40 days for a female to begin laying eggs. The more northerly the breeding area is, the shorter this period of time becomes. In the Tobolsk region , oviposition begins 15 to 20 days after the arrival of the female. On the Yamal this interval is five to ten days.
The nest is only built by the female on the ground. It is usually located in the reed zone on a dry elevation. Particularly in steppe and dry grass regions, pintail ducks sometimes breed at a distance of several kilometers from the water. Most nests, however, are not more than 100 meters from the nearest body of water. The shallow nest is made of plant material and is padded with down. A clutch consists of eight to twelve light green eggs. The female lays about one egg a day. The egg size is around 55 to 28 millimeters. The average egg weighs 45 grams, with the shell accounting for seven percent of the weight. If the clutch is destroyed, the female will be able to lay a replacement clutch by around the end of July.
The young are brooded and raised by the female alone. The drakes initially stay near the nest. As the breeding period progresses, the pair bond between drake and female becomes increasingly looser. The drakes increasingly join other drakes and finally move towards the moulting sites. The female incubates the clutch for about 22 to 24 days. After hatching, the newly hatched downy chicks are led by the female to the next body of water, where they live for the first few weeks on insects that they pick from the surface of the water. The chicks can fledge after 46 to 47 days. However, they usually remain with the mother bird until it has completely moulted.
About two out of four hatched chicks survive the first two weeks of life. Only every fourth chick, on the other hand, fledges. The maximum age that has so far been proven for a pintail is 27 years and five months. The average lifespan of a pintail, however, is significantly lower. However, detailed studies are lacking. However, it is very likely that the average age of a pintail population is two years, similar to that of the mallard.
Pintail ducks feed mainly on aquatic plants, which they ingest in shallow water. The respective food composition depends on the local food supply. As is characteristic of the gudgeon ducks, they often stand upside down in the water when foraging and keep their balance by moving their legs slightly. Due to the long neck, pintail can also ingest food components that are found 30 centimeters below the water surface. Pintail ducks therefore use water zones that are beyond the reach of other green ducks such as the teal or mallard. Even in very shallow water, the head and neck are completely submerged in the search for food and the bottom sediment is searched. Food is mainly consumed in the evening and at night. The pintail ducks spend most of the day resting.
The diet consists mainly of plant material such as seeds and rhizomes from aquatic plants. Occasionally, pintail ducks look for roots, cereal grains and other seeds on land. This behavior is more pronounced in other ducks of the Anas genus. Agricultural crops that are eaten by pintail ducks include wheat , barley , millet , buckwheat and rice .
In contrast to the more vegetarian diet, females eat a high proportion of animal food during the breeding season. Before the eggs are laid, this proportion is 56 percent; it rises to 77 percent during the laying phase and then drops to 29 percent. In the case of females that do not lay eggs, the proportion of animal food is only 4.6 percent. The animal diet of pintail ducks consists mainly of the larvae of various aquatic insects as well as molluscs , amphipods and little bristles . If the females do not have sufficient animal food available, this has an impact on the clutch size. Females who only received wheat to eat during this time had a clutch that was up to 46 to 50 percent smaller.
Predators and diseases
The pintail clutches and chicks are endangered by predatory mammals such as foxes and badgers and by birds such as gulls , crows and magpies . Adult pintail ducks can usually escape the stalking of predatory mammals by being blown up. However, brooding female pintail ducks are often surprised at the nest by large predatory mammals such as the bobcat or the red fox . Some birds of prey, such as the hawk, are able to strike pintail ducks on the ground. Some falcons, including the gyrfalcon in particular , are fast and powerful enough to hunt down flying pintails.
Pintail ducks are attacked by a number of parasites. These include cryptosporidia , giardia , tapeworms and featherlings . Other bird diseases also occur in the pintail. It is often the species with the highest mortality rate when botulism or fowl cholera breaks out among aquatic fowl . Pintail ducks can also get H5N1 bird flu .
The pintail is one of the species that falls under the Agreement on the Conservation of African-Eurasian Migratory Waterbirds ( AEWA ), but it has no special protection status under the CITES agreements.
The global population is currently estimated at 6.1 to 7.7 million individuals. The IUCN assumes that the population has not decreased by more than 30 percent in the last few years or in the last three generations. Accordingly, the species is classified as least concern or not threatened by the IUCN .
The best-documented inventory figures are for North America. They show that the species as a whole is subject to strong population fluctuations: In North America, the breeding population fell between 1957 and 1964 from the original 10 million individuals to 3.5 million. The main cause of the decline was, in addition to a prolonged drought in the prairie areas, a number of disease epidemics, which were severely affected by pintail. The population recovered to 5.9 million individuals by 1969 and remained stable at around 5.6 million individuals in the 1970s. In 1988, however, the North American population was only two million pintail ducks. According to investigations by Canadian and US authorities, the causes of the population collapse include hunting overexploitation, loss of habitat and climatic influences. In the two botulism epidemics in 1997, which killed around 1.5 million waterbirds in Canada and the USA, pintail populations were again particularly badly affected. In 1999 the breeding population was around 30 percent below the long-term average. The Eurasian breeding population is also apparently declining. This is mainly related to the number of pintail ducks that hibernate: While the number of pintail ducks hibernating in western Africa has remained stable at 1.2 million over the past thirty years, the pintail population in northwestern Europe declines slightly in the winter half-year. The number of pintail ducks wintering in the Black Sea and the eastern Mediterranean is falling by an average of 6.4 percent annually. There are insufficient figures for other wintering areas to draw conclusions about the development of the population.
In her assessment of the future development of the population, ornithologist Janet Kear assumes that the pintail population will continue to decline in the future. The traditional hibernation areas are threatened by ongoing industrial development. In North America, the breeding population of the prairie areas declined dramatically due to habitat loss despite protective measures. A research team that, on behalf of the British Environmental Protection Agency and the RSPB, investigated the future development of birds on the basis of climate models, comes to a similar conclusion and assumes that the pintail duck will be affected by global warming by the end of the 21st century a widespread disappearance in Western, Northern and Central Europe. According to this forecast, the distribution area will decrease significantly and shift to the north.
Pintail ducks and people
Because of their vigilance and their fast flight, pintail ducks are not easy prey for the hunter, but this increases the attraction of hunting them for many hunters. Their meat is also said to be of good quality. It is hunted by humans in almost the entire range. In Germany, pintail ducks make up less than 10 percent of the duck species hunted, with the hunt almost exclusively falling victim to migrants. With the exception of Bavaria, Bremen, Saxony and Saxony-Anhalt, northern pintail ducks are spared all year round . There have been no more kills in Switzerland since 2007. In Austria the pintail is not a game bird that can be hunted. In the USA and Canada, on the other hand, the pintail is an important game bird for hunting. Although the pintail is one of the most common duck species worldwide, hunting and other factors influencing the population have led to population declines, so that this species was temporarily placed under protection or hunting restricted. Local overexploitation for hunting can have a negative impact on the population figures of a very large distribution area, since the pintail, which opportunistically colonizes new habitats in the summer half-year, show a high level of loyalty to their wintering sites.
Humans, among other things, change the pintail's habitats in such a way that they can no longer be used as breeding grounds. Above all, the draining of swamp and marshland for the purpose of converting it into agricultural land is influencing the population. In many parts of the distribution area, the agricultural planting and sowing time also falls during the period in which the pintail ducks have already set up their nests. A large number of clutches are therefore destroyed by agricultural work. In a Canadian study, more than half of the nests observed fell victim to plowing and egg work . Studies in North Dakota confirm this result.
Hunting with lead shot and fishing with lead core is considered to be the most important cause of lead poisoning, which is particularly common in green ducks. In a Spanish study, pochard and pochard were among the species that ingested lead most frequently. In most Western European countries, the USA and Canada, the use of lead ammunition for hunting water fowl is now banned.
The species was classified in 1758 by Carl von Linné in his Systema naturae as Anas acuta . While anas is the Latin name for duck, acuta is derived from the Latin verb acuere , which means to sharpen or point.
Within the species-rich Anatinae genus of Anas , the Pintail most closely with the South American's yellow-billed pintail ( Anas georgica ) and Eaton's Pintail ( Anas eatoni ) related. The kerguelen duck, which occurs as an island in the southern Indian Ocean, has long been considered a subspecies of the pointed-tailed duck. It is now given its own species status. As early as 1824, James Francis Stephens proposed to assign the species group of pointed- tailed ducks to its own genus with the genus name Dafila . This proposal is confirmed by new morphological and molecular biological findings, but has not yet been generally accepted.
Despite the large distribution area, this species has no subspecies, it is therefore called a monotypical species. Breeding pairs form in the wintering areas, where pintail ducks from different distribution areas meet. This behavioral characteristic as well as the ability to colonize new breeding areas opportunistically have meant that no discernible morphological differences have so far developed.
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