Tree pipit
| Tree pipit | ||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
Tree pipit ( Anthus trivialis ) |
||||||||||||
| Systematics | ||||||||||||
|
||||||||||||
| Scientific name | ||||||||||||
| Anthus trivialis | ||||||||||||
| ( Linnaeus , 1758) |
The tree pipit ( Anthus trivialis ) is a species of bird from the family of the stilt and pipit (Motacillidae). The bird, which is common in Central Europe in summer but is optically inconspicuous, can be observed above all at the edges and clearings of forests, as, in addition to a population of tall trees and bushes, it also requires open areas with low vegetation. He is particularly noticeable there because of his singing.
The tree pipit is a long-distance migrant that overwinters in the vegetation zone of the high grass savannahs of West and East Africa.
Surname
Despite its inconspicuous appearance, the tree pipit is noticeable because it lets out its bright and cheerful-looking calls from exposed singing stations or while singing. Accordingly, this bird species has a number of different common names in the vernacular. Some, such as the tree, wood, herbaceous, Spitz or skewer lark, allude to the lark-like behavior of the tree pipit. In Austria, the bird is also popularly called Ziepe or Schmelchen. Grienvögelchen or Greinerlein are other old and meanwhile uncommon names.
The term Baumpieper used almost entirely in the German language today assigns the type the correct genus and assigns similar to tawny pipit and meadow pipit on the preferred habitat of this bird out.
The scientific species name "trivialis" (= common, common), on the other hand, expresses that the tree pipit is common compared to the other pipit species.
_at_Sindhrot_near_Vadodara,_Gujrat_Pix_239.jpg)
Appearance
Height and weight
With an average length of 15 centimeters, the tree pipit is about the same size as a house sparrow . However, it is more graceful and slimmer than this and therefore looks larger. The wing length in male birds is on average almost 90 millimeters, in females the wings are about four to five millimeters shorter.
The tree pipit's body weight during the reproductive period is around 22 to 24 grams. At the beginning of the autumn migration the birds are usually heavier; Particularly well-fed birds can then weigh over 30 grams. In the case of tree pipiters that are on the return flight from their wintering quarters in Africa, a weight of only 16 grams has been found in isolated cases.
Other features
The plumage shows no gender-specific differences. The upper side of the body is yellow to olive brown with diffuse blackish longitudinal stripes that are more pronounced on the top of the head. The rump and upper tail-coverts are a little greener in color than the rest of the upper side of the body and are only weakly striped in individual individuals. The underside of the body is cream-colored to yellowish with a strongly striped chest and goiter sides. The throat, chest and sides of the neck have a more pronounced shade of yellow. On the flanks, the stripes are much less wide than on the chest. The outer control springs are partially white. The elytra are brightly lined, creating two light, cream-colored wing bands. The hems formed by the point hems of the middle arm covers can be seen most clearly. The tail protrudes over the wing tips by about 3.5 centimeters.
There is a light, not always clearly visible, eye stripe above the eye. The iris is dark brown, the eye ring formed by two rows of feathers is cream-colored. The nostrils are exposed. The top of the beak and the tip of the lower beak are black-brown. The rest of the lower mandible becomes lighter in the direction of the root and lower jaw and is yellowish to flesh-colored. The legs are reddish-flesh-colored, while the feet are pink to yellowish-flesh-colored. The claws are brightly horn-colored.
Young birds are very similar to adult birds. Their plumage is a little more yellow on the upper side of the body, the black-brown longitudinal stripes a little more pronounced. Characteristic of the plumage of the young birds is a black-brown spot on the rump. This is absent in adult birds.
A strongly curved rear claw, which can be between 6.6 and 8.6 millimeters long, is species-specific for the tree pipit. Compared to the length of the rear toe, it is either shorter than this or at most the same length. Both in larks and in the other representatives of the pipit, on the other hand, this rear toe is longer and less curved. Only the forest pipit found in north and east Asia has a rear toe that is similar in shape and length. The sixth of the wrist wings is one to six millimeters shorter than the seventh to ninth. With the meadow pipit, on the other hand, these hand wings are of the same length.
Way of flight and movement
When tree pipit are aroused or sit on a song waiting room, a regular, flat tail bobbing can be observed. They crouch on the floor. Alarmed tree pipits immediately seek cover in bushes or in the branches of trees.
Similar to wagtails - but without their intensive tail rocking - the tree pipit searches herbaceous or grassy areas for food. The wings are laid out and the tail forms a line with the back, the legs are bent so much in the knee joint that the underside of the body is only just above the ground. The head carried upright and the neck nod in rhythm with the triple steps. He picks his prey either from the ground or from plants. If he sees a prey further away, his sequence of steps accelerates, the head is then pushed slightly forward, the bird then appears to be more “crouched”. The tree pipit travels in a lengthwise direction on branches. It preferably moves from the inside out.
In cross-country flights, a series of strong and rapid wing beats alternate with short gliding phases. During these gliding phases, the wings are placed against the body. The loss of altitude and speed is so small that the flight is not as wavy as that of the meadow pipit.
Possible confusion with other bird species
The meadow pipit is so similar to the tree pipit that you have to use the flight and way of life as well as the song for identification - in addition to a few slight distinguishing features in body structure and plumage color. The characteristic characteristics of the tree pipit, which are described above, can only be used for identification in the field if the observation conditions are very good. In contrast to the more delicate meadow pipit, the tree pipit has a stronger beak and a more yellowish chest. While tree pipits can often be seen sitting on tree branches, meadow pipits usually stay on the ground and have a “hopping”, short flight. The tree pipit, on the other hand, flies jerkily in flat waves.
The woodlark , which can also be observed in the tree pipit's habitat and has a plumage similar to that of the tree pipit, can be distinguished from the tree pipit by its significantly shorter tail and its more distinctive and lighter cream-colored eye stripe.
voice
The song of the tree pipit can only be heard in good weather. Then he lets out a faint chirping before sunrise, which he either delivers from a low seated control room or even directly from the ground. In the event of rain, storms or cold spells, it stays in silence in dense ground vegetation.
The singing flight of the tree pipit takes place from early morning to noon and then again in the late afternoon. It is primarily used to mark the territory, is loud and melodic and is performed in a characteristic way. The starting point of the singing flight is usually the top of a tree, but occasionally the bird also takes off from the ground. The bird sits in a crouched position for one to two seconds, pushes itself diagonally upwards in the air with both feet, silently climbs 10 to 30 meters high and lets out a softly beginning and increasingly loud "ziziziwiswiswis" shortly before the highest point of the flight, this is often followed by a canary-like scooter, and in a six to twelve second gliding flight, the bird returns with stiffly spread wings under loud "zia zia zia zia" that sounds good to humans either to the starting point or to another singing station. Because of the high speed that the tree pipit reaches in downward gliding flight, it does not head for its landing site directly. He aims at a place below the control room and swings up to her with a few flaps of his wings.
How often the singing flight is repeated depends on the time of year, the prevailing weather, the mating status of the bird and the singing activity of the neighbors. In Central Europe, singing flights in which the singing is performed in full are typical for the period from the end of April to the end of July. Mated territory owners sometimes rise every two to six minutes to sing in flight. Within the basic pattern described above, the singing is very variable intra- and inter-individually. A single bird adheres to the beginning and end of its song exactly. The length of the individual vocal stanzas is determined, for example, by the length of the flight route, with individual phrases and vocal elements being combined in different order. The repertoire of phrases and elements varies depending on the male. A clear dialect formation has also been proven for the tree pipit: populations of individual regions can be differentiated on the basis of the element types of the beginning and end of the song.
The Reviergesang can also be performed from a singing station. In this case, however, it is usually shorter and only partially presented. The tree pipit also has a number of different sounds. The metallic sounding "siiit siiit" is a warning or contact call that can often be heard at intervals of half a second. The hastily called "sip-sip-sip", which rises in pitch, is also an alarm call that can be heard when an enemy approaches the precinct. "Tsieb" serves primarily as a contact call. Only these contact and warning sounds can be heard in winter quarters.
distribution
Breeding area
The tree pipit is a breeding bird of the temperate and boreal zones of Eurasia. The eastern limit of distribution is not sufficiently secured and is controversial. According to some authors, the distribution area of the tree pipit extends as far as the southern Verkhoyansk Mountains , which are part of the East Siberian mountainous region. It reaches its northernmost distribution area in Europe around the 70th and in Asia at the 65th north latitude.
To the west, the tree pipit is absent on Iceland and Ireland , the Shetland Islands , Orkneys and the Outer Hebrides , while it is still found in Great Britain . In the south, its distribution area extends to northern Spain . The tree pipit is absent in Portugal and central and southern Spain, as well as in most of the Mediterranean islands and in southern Greece . The northern Turkey and the mountainous regions of the Caucasus , the North of Iran and the northwestern Mongolia are among the breeding grounds of the Tree Pipit. The southern limit of distribution is very uneven. In the steppe regions of West and Central Asia, tree pipits no longer occur from latitude 50 ° north. In the Central Asian mountain regions, the distribution area extends south to the Pamir and from there in a south-westerly direction to the north-west of the Himalayas . In addition, there are brood occurrences isolated from the rest of the distribution area in northwest India. In total, the breeding area of the tree pipit covers around 14 million square kilometers.
Train and winter quarters
The tree pipit is a long-distance migrant that moves broadly to winter quarters. The migration begins occasionally in June and is most pronounced in August and early September. As a rule, breeding birds remain in the vicinity of their territory for a few weeks after the breeding business has been concluded and during this time they build up fat reserves. The European populations up to about the 40th east longitude migrate over the Iberian Peninsula or Northern Italy. High mountains are flown over on this train, with tree pipit preferring good weather. On the way to the wintering quarters, the breeding birds of Europe and probably also of western Siberia usually cross the Sahara . The wintering quarters stretch south of the Sahara across the entire African continent, with the southernmost wintering quarters in northern South Africa . You can find them there mainly in the Transvaal .
South Mauritania , Senegal , Gambia , Guinea , Sierra Leone , Liberia , southwest Mali, the Ivory Coast , Burkina Faso , Ghana , Togo , Benin , the southwest of Niger and central and southern Nigeria are among the wintering areas in West Africa. In East Africa the wintering quarters stretch from southern Sudan , Ethiopia and Somalia to the Transvaal and southern Mozambique .
The tree pipit, whose breeding area is in Asia, overwinter in southern Asia and can then be observed, for example, in India and Bangladesh , Pakistan , Afghanistan and the Arabian Peninsula via southern Iran to Turkey. Tree pipit in the Asian breeding area also regularly overwinter in the Seychelles . Occasionally there are also overwintering populations in the Maldives and in the east of Japan .
The European breeding birds begin to withdraw from their winter quarters around February. However, the start of the withdrawal may be postponed until the beginning of April. In the case of extensive high pressure zones , the return occurs very quickly, while cold air zones slow down the return significantly. Tree pipit can be seen sporadically in Central Europe from the second half of March. However, the main return period is April, with stragglers occasionally not returning to their breeding areas until the second half of May. The majority of the population usually arrives between five and fifteen days after the first birds, with the males arriving in the breeding areas earlier than the females.
habitat
Breeding areas
As a ground-breeder, the tree pipit needs a habitat during its reproductive period that, in addition to a population of tall trees or bushes, has enough light spots with a sufficiently dense herbaceous layer. Accordingly, tree pipits are absent in extensive arable land or grassland areas, as are characteristic of Friesland or North Holland . The tree pipit is not bound to a specific tree species. It occurs in coniferous forests as well as in deciduous or mixed deciduous forests. The assumption occasionally expressed in the past that tree pipits had a bond with conifers, like the golden cockerel , has now been disproved.
In addition to loosened, sunny forest edges, clear-cutting, afforestation areas and forest clearings as the most important breeding habitats, tree pipits also use heaths , vineyards and bogs , provided they have sufficient trees and a dense layer of herbs. Places exposed to the sun are preferred. On the other hand, they are rarely seen in cemeteries, orchards or in parks, as the herbaceous layer is usually not thick enough here.
The height distribution of the tree pipit is also influenced by the presence of herbaceous or dwarf shrub layers. It occurs there regularly up to the tree line. In the Alps it breeds up to an altitude of 2300 m and in Austria the main distribution of the tree pipit is even in the Montan level of the Alps. In the Himalayas, there is evidence of breeding for the tree pipit at an altitude of 4,200 meters.
Migration and winter quarters
Tree pipits that are on their way to their wintering quarters use agricultural land more than during the breeding season. During their foraging for food, they can then also be seen in meadows and pastures as well as on arable land where root crops or clover and alfalfa are grown. Here the vegetation offers them sufficient cover. Arable land such as harvested grain fields are only sought in the vicinity of bushes.
In the wintering area, like in its breeding areas, the tree pipit prefers to stay in semi-open to open terrain near the woods. Accordingly, it can also be found here at the edges of the forest or in clearings of acacia forests . It can also often be seen on the edge of coffee, banana or oil palm plantations and regularly in gardens.
Food and subsistence
.jpg)
The diet consists almost exclusively of small, soft-skinned insects . Seeds or other parts of plants have been found sporadically in the stomachs of tree pipiters, but they only represent a very small part of the diet. The main component of the diet is made up of the caterpillars of butterflies and grasshoppers. Prey also includes bedbugs , beetles , aphids , parasitic wasps , ants and caddis flies . The food composition can shift if, for example, due to a mass development, the oak moth's caterpillars are in abundance . Beetles, caterpillars and bedbugs are also the preferred food components in the wintering quarters. However, tree pipits also eat termites here .
To cover their fluid requirements, tree pipits mainly use the water droplets that hang on plants. The tree pipit is seldom seen in open water. It finds its food both on areas with low vegetation and on trees. It is still disputed what proportion of the total food the prey found on trees has and whether there are seasonal fluctuations. It is generally assumed that the tree pipit finds most of its food on the ground.
The tree pipit not only uses its breeding area to acquire food, but also regularly uses an additional feeding area that does not necessarily adjoin the breeding area. It can be up to half a kilometer away and is often used by more than one pair of tree pipit.
Young birds that have become independent often form loosely cohesive flocks that roam together in the area near the breeding site. The size of these troops increases until they move away.
Breeding biology
The breeding ground
Tree pipits have not yet mated when they return to the breeding grounds, and the first to return are usually perennial males. They are followed by perennial females and only then by the annual males. Returning males immediately begin to occupy territories. The returnees are faithful to the place where they were born; young birds also return to their place of birth. However, due to the instability of the habitats they use as breeding areas, such as clearcuts and clearings, the breeding sites regularly shift. Tree pipiters lead a monogamous seasonal marriage, whereby loyalty to the territory can lead to previous partners mating again.
The breeding area includes the area in which the nest is located and which the male and female defend against conspecifics. Depending on the quality of the habitat and the population density, the size of the breeding area varies between 0.3 and 2.5 hectares. The males returning first, who are not yet exposed to such great competitive pressure, initially occupy a much larger area. Under the pressure of conspecifics returning later, this is then gradually reduced.
The territorial boundaries are marked by the singing of the male and - after the territorial boundaries have been determined - respected by the conspecifics. Neighboring pairs avoid a direct crossing of the territory by flying over the territory of other pairs of tree pipit at high altitude.
If a male tree pipit intrudes into an already occupied territory, the song of the territory owner becomes louder and more excited. If the area intruder does not respond by withdrawing, the area owner flies towards him singing. Most of the time this is enough to get an intruder to retreat. Real attacks on conspecifics are rare. The birds attack each other with wing and beak blows and claws. Even foreign females are driven out of the territory by the male, albeit with less intensity. Females occasionally support the males in maintaining their territory and defend the territory on their own in the absence of the male. Unlike the male, they do not allow any chants to be heard.
The nest and the rearing of the young birds
The nest is hidden on the ground under tufts of grass , dwarf shrubs, ferns or under low bushes. Basically, the nests are designed in such a way that there is a privacy screen upwards. Places with a vegetation with forest twinkles ( Brachypodium silvaticum ), wiry Schmiele ( Deschampsia flexuosa ) and riding grass ( Calamagrostis epigeios ) are used particularly frequently to create the nest. The tree pipit uses dry grass, a lot of moss and dry leaves to build nests. The hemispherical nest hollow is padded with fibers, roots and thin blades of grass. The nest is only built by the female.
The clutch usually consists of five eggs that weigh two to three grams and are very variable in color. The basic color of the eggs in a clutch is similar, but depending on the female they are gray, purple, green, rusty brown or pink. As a rule, they are spotted dark brown, although the spotting is also very variable. It ranges from thin, small dots to large, coarse spots that run into one another in such a way that the eggs appear almost completely dark brown or blackish gray.
In Central Europe, breeding begins in May. Only the female breeds. It leaves the nest between twelve and fifteen times a day to look for food. The incubation period is twelve to fourteen days. The young birds stay in the nest for ten to twelve days. At this point they are not yet fully fledged and are hiding in the herbaceous layer of the soil. Both parent birds take care of the young birds even after they have moved away from the nest. The young birds are fed until they are around 25 days old. However, the number of feedings decreases with increasing age of the young birds. The young birds reach their ability to fly between their fifteenth and twentieth days of life.
If the first brood fails, most tree pipit pairs start with a replacement brood. A high proportion of tree pipiters who have successfully raised their first brood start with a second brood. In exceptional cases there is even a third attempt at breeding if the young of the second brood have flown out successfully. As a rule, the clutch size decreases as the breeding season progresses. On average, a couple successfully raises three to four young birds per year.
Life expectancy, existence and exposure
The average age of tree pipit populations is estimated to be less than two years. In a study in Kalmthout , Belgium , observing a tree pipit population over five years, the number of annual birds averaged just under fifty percent. Among recaptured ringed birds, four percent were older than five years. The oldest ringbird recaptured so far was seven years and eight months old. The influence of predators , birds of prey , corvids , shrikers and parasites on the mortality of nestlings, young birds and adult tree pipiters has not yet been adequately investigated. Among the birds that were examined at the Heligoland ornithological station, tree pipit is one of the bird species that are most frequently infested by the tick species Ixodes ricinus . However, weather conditions have a major impact on the survival rate of tree pipiters. During the migration, the mortality rate is high, especially in cold and wet weather. In winter quarters, drought in particular has an impact on the survival rate.
The fall population of the tree pipit is estimated to be around 370 million individuals for the entire species area of around 14 million square kilometers. In Germany, the breeding population for the years 2005 to 2009 is estimated at 250,000 to 355,000 breeding pairs, for Sweden on the other hand at 4 million and for Finland at 1.6 million breeding pairs. The stock fluctuates depending on suitable habitats: it increases when open forest areas arise after storm damage and pest infestation. In Finland, the tree pipit population benefited from large-scale deforestation measures and was able to expand its range to regions that were previously dense with forest. The populations decline when large areas of near-natural mixed forests are converted into coniferous wood cultures or low-yielding heather and moorland areas are reforested.
In the Red List of Germany's breeding birds from 2015, the species is listed in Category 3 as endangered.
Systematics
Despite the very large distribution area, only two subspecies have been described so far. The populations that breed in the Himalayan area are grouped together in the subspecies Anthus trivialis haringtoni . These differ from the nominate form Anthus trivialis trivialis primarily in that they have a slightly wider beak at the base. Within the nominate form there are indeed differences in the plumage coloration - for example, the populations native to Scotland have a reddish-yellow chin area - the differences are minor and do not show constant regional differences, so that no further differentiation into subspecies has been made so far .
Sources and literature
literature
- Per Alström and Krister Mild: Pipits & Wagtails of Europe, Asia and Northamerica , Christopher Helm Ltd., London 2003, ISBN 0-7136-5834-7 .
- Urs Glutz von Blotzheim: Handbook of the birds of Central Europe - Volume 10 / II - Passeriformes (1st part) . Aula Verlag, Wiesbaden, 1985.
- Faansie Peacock: Pipits of Southern Africa - The complete guide to Africa's ultimate LBJ’s . Pretoria 2006, ISBN 0-620-35967-6 .
- Rudolf Pätzold : The tree pipit . Ziemsen publishing house, Lutherstadt Wittenberg, 1990, ISBN 3-7403-0235-6 .
Web links
- Tree pipit at www.reuber-norwegen.de
- Anthus trivialis in the endangered Red List species the IUCN 2008. Posted by: BirdLife International, 2008. Accessed on December 18 of 2008.
- Videos, photos and sound recordings for Anthus trivialis in the Internet Bird Collection
- Age and gender characteristics (PDF; 1.7 MB) by Javier Blasco-Zumeta and Gerd-Michael Heinze (English)
- Feathers of the tree pipit
- Video: Singing flight of the tree pipit . Institute for Scientific Film (IWF) 1980, made available by the Technical Information Library (TIB), doi : 10.3203 / IWF / D-1399 .
Footnotes
- ↑ Blotzheim, p. 586
- ↑ detailed information on body weight and height from a number of different studies can be found in Pätzold, p. 18; in Glutz von Blotzheim, p. 578 f and in Allström and Mild, p. 135
- ↑ A very detailed description of the tree pipit plumage can be found in Peacock, pp. 135 to 137, and in Glutz von Blotzheim, pp. 576–579
- ↑ Glutz von Blotzheim, p. 578
- ^ Peacock, p. 135
- ↑ Pätzold, p. 13. There are also further details and dimensions of the body structure (p. 13–23)
- ↑ Peacock, pp. 100 and 137
- ^ Peacock, p. 137
- ↑ Glutz von Blotzheim, p. 599
- ↑ Allström and Mild, p. 132
- ↑ Glutz von Blotzheim, pp. 580-582
- ↑ Glutz von Blotzheim, p. 584
- ↑ Glutz von Blotzheim, p. 582 f.
- ^ Peacock, p. 138
- ↑ a b Peacock, p. 139
- ↑ Allström and Mild, p. 139
- ↑ Blotzheim, p. 585
- ↑ Allström and Mild, p. 139
- ↑ a b Pätzold, p. 12
- ↑ Blotzheim, p. 588
- ↑ Blotzheim, pp. 587f
- ↑ Glutz von Blotzheim, pp. 586f
- ↑ Glutz von Blotzheim, pp. 588f
- ↑ Glutz von Blotzheim, p. 585
- ↑ Michael Dvorak et al. : Atlas of the breeding birds of Austria . Umweltbundesamt 1993, ISBN 3-85457-121-6 , p. 287
- ↑ Pätzold, p. 31
- ^ Glutz von Blotzheim
- ↑ Glutz von Blotzheim, p. 601
- ↑ Glutz von Blotzheim, p. 602
- ↑ a b Glutz von Blotzheim, p. 593
- ↑ Glutz von Blotzheim, p. 592
- ^ Pätzold, p. 69
- ^ Walter Czerny: What bird is that , Deutscher Bücherbund, Stuttgart 1973, p. 317
- ↑ Glutz von Blotzheim, p. 595
- ^ Glutz von Blotzheim, p. 607
- ↑ Glutz von Blotzheim, p. 608
- ^ Einhard Bezzel: Vögel , BLV Verlagsgesellschaft, Munich 1996, ISBN 3-405-14736-0 , p. 369
- ↑ Glutz von Blotzheim, p. 597
- ↑ a b Glutz von Blotzheim, p. 598
- ↑ Glutz von Blotzheim, p. 586
- ↑ Christoph Grüneberg, Hans-Günther Bauer, Heiko Haupt, Ommo Hüppop, Torsten Ryslavy, Peter Südbeck: Red List of Germany's Breeding Birds , 5 version . In: German Council for Bird Protection (Hrsg.): Reports on bird protection . tape 52 , November 30, 2015.
- ↑ Allström and Mild, p. 134
