The swallowing tree ( Tachycineta bicolor ) is a migratory passerine bird that breeds in North America and winters in Mexico, Central America and the Caribbean. This is a very rare tramp to Western Europe.
Video Tree swallow
Taxonomy and etymology
Swallow trees are usually placed in the genus Tachycineta, although occasionally placed in the genus Iridoprocne, along with swallowing of mangrove, white swallow, white-winged swallow. , and swallowing Chile.
The position of the swallow tree in relation to other members of Tachycineta is unbreakable. In studies based on mitochondrial DNA, these birds are placed at the bottom (which means the first branch in the species tree) in violet green birds, which are themselves placed at the base of gold and the Bahamas swallow. Although mitochondrial DNA is recommended to be a better indicator of evolutionary change because of its shorter merging time, the underlying analysis can suffer because mitochondrial DNA is inherited from only one source, thus possibly making it worse than the core DNA of several loci in representing the entire group phylogeny. A study based on nuclear DNA, in contrast to mitochondrial DNA studies, placed swallow trees swallowing into the entire genus Tachycineta .
Commonly accepted genera names are from Ancient Greek takhykinetos , "fast moving", and the specific bicolor is Latin and means "two colors". The name of another genus, Iridoprocne , is derived from the Greek iris , which means rainbow, and Procne, a figure supposedly turned into a swallow.
Maps Tree swallow
Description
The swallow has a length of between about 12 and 14 cm (4.7 and 5.5 inches) and weighs about 17 to 25.5 g (0.60 to 0.90 oz). Men have mostly blue-glazed-green top , with wings and tail becomes blackish. The bottom and white cheek patch, even though underwing cover is gray brown. Females can be distinguished from men because the first is more dull, and sometimes has a brown forehead. In addition, the first year females have the top of the chocolate, with a variable number of blue feathers. Second year women sometimes keep some of these chocolate feathers. Teenagers can be distinguished into brown tops and washed brown grays.
Voice
Swallow song is three long and descending notes that end with a liquid chirping. The song is repeated. The alarm call is "peeh" or "pee-deeh"; this call can serve to silence an older nest that begs when the predator is near.
Distribution and habitat
Swallow bird seeds in North America. Its reach extends to northern Alaska and to tree boundaries in Canada. It is found as far south as Tennessee in its eastern reach, California and New Mexico to the west, and Kansas at the center. Sometimes it breeds further south in the United States (US). The winter series is mainly on the southern US and southern coast, along the Gulf Coast, to Panama and the northwest coast of South America, in addition to being found in the West Indies. When a bird goes back to the nest, it usually does not change the breeding grounds.
Habitat swallowing is mainly in open and forested areas, especially near water. The fact that he can deal with open areas is due to the construction of nesting boxes in these areas.
Behavior
Although aggressive during mating season, walet trees are easy to mingle outside the mating season, forming a flock of poultry that sometimes amount to thousands of birds.
Breeding
Swallow trees usually repent in the same area to breed again; only about 14% of women and 4% of men spread to breeds on new sites per year. However, this spread is influenced by the success of captive breeding; about 28% of farmers broke up after they failed to become girls, compared to 5% that spread when they succeeded. Most do not spread far, usually breeding in locations less than 10 kilometers (6.2 miles) from the original land. Once the nest is found in existing holes, usually in trees and artificial structures such as pipes and fence posts, and in nestboxes, men perched nearby and often called. Lack of nest sites can lead to fights between birds, sometimes causing death. Hole holes average 3.4 meters (11 feet) above ground level, although about 45% of them are less than 2 meters (6.6 feet) above the ground. The tree swallows the nests both in loose and clandestine groups. When nested in a loose group, the nest is usually 10 to 15 meters (33 to 49 feet), and those closer to the distance are usually further apart in terms of laying dates. In the natural cavity, the nest is about 27 meters (89 feet) apart from its neighbors. These birds usually maintain an area around the nest with a radius of about 4.6 meters (15 feet), in addition to additional nests within the area. The nest cups themselves are made of grass, moss, pine, and aquatic plants, and are coated with feathers, all of which are collected mostly by women.
The dating to swallow birds begins with a man attacking an unknown woman; this can be stimulated by women who fly with flying wings, which may be an invitation to court. The man can then take a vertical posture, with the tail raised, slightly spread, and with slightly drooped wings. It stimulates women to try and land on a man's back, but he flies to prevent this; this is repeated. After the trial of the female gentleman, he flies to the site of his chosen nest, and the woman checks it out. The couple's ties take time to develop. During intercourse, a man hovers over a woman, and then rides it, giving an aggression appeal. He then made a cloaca contact with the woman holding her neck on her bill and stand in his slightly outstretched wings. Copulation occurs several times.
Eggs are laid from early May to mid June and chicks mature between mid-June and July. When the egg is placed it is affected by the latitude, the age of the female, and the length of the female wings. On average, birds in the southern part of the breeding range proliferate earlier than in the north. The length and age of the female wings are both correlated inversely with the breeding time. Generally lay eggs when the temperature and abundance of food (which can be caught by females) is good enough for females to start laying eggs. This observation supports the theory that the swallow tree is a revenue breeder (breeding based on food conditions during the laying season). This species is generally monogamous, but up to 8% of male males are polygynous. Polygynia is influenced by territory: men with nestboxes of at least 5 meters (16 feet) are more likely to be polygamous. It is suggested that polygamy is dependent on the conditions during the laying season: better conditions, such as food abundance, allow women in polygamy who do not receive help in foraging to put more eggs.
Swallow trees have a high rate of extra-pair couples, with 38% to 69% of the hives being the product of extra-pair couples, and 50% to 87% of mains containing at least one nestling which is the result of extra-pair copulation. One factor that may contribute to this is that women have control over copulation, making the father's keepers ineffective. Extra-father partners do not change the level of care of parents who contribute to swallow, contrary to other birds. Swallow trees also differ in terms of the arrangement of an extra partner's father; in a study that found the paternity of 35 additional pairs, it was determined that 25 young couples were from fathers from sites near the nest where females were located, about 3 of the sites within 2 kilometers (1.2 miles), and 7 had floating fathers (which are present in breeding grounds that may not breed). In the swallow tree, floating thereby helping the man in good condition produce more chicks, while allowing males in bad condition to be successful through parental care.
How the father of an extra couple is chosen and why women even breed with other men (because they can control intercourse) is controversial. One theory, called the genetic compatibility hypothesis, suggests that increased hereditary fitness results from increased heterozygosity, and thus that swallowed female trees would prefer to mate with those who have an allele that is more different from them. This theory is justified on the basis that the youth produced from extra-pair couples is usually more heterozygous than couples in couples. In the supplementary support of this theory, women tend to be able to judge, after intercourse, whether high-quality male sperm and whether she should allow her to impregnate her. Another theory, called good gene theory, says that women choose an extra-paired male based on whether they have a good gene that will affect the survival and success of marriage. This is supported on the basis that it is able to explain why some trees swallow not have additional young couples, while others do so. While this is true, there is criticism for the lack of phenotypic differences between the extra paired men and the coupled men. However, there are results that may support this theory. For example, in a 2007 study, it was found that increased brightness of the feathers and increased age in extra-partner men, together, increased the number of extra-young couples.
The swallow tree places a clutch of two to eight, though usually four to seven, pure white, and translucent at the time of laying, an egg about 19 by 14 cm (7.5.5.5 inches). These eggs are incubated by females, usually after the second-to-last egg is placed, for 11 to 20 days, although most hatch after 14 to 15 days. About 88% of the nests produce at least one nestling, although these are inherited by bad weather and younger females. They hatch a bit asynchronously, with an average of 28 hours between the time the first and last eggs are laid. The placement sequence predicts the order of hatching, with the eggs generally hatch in the order they are placed. When the mother hatches asynchronously, a heavy hierarchy is erected, with hatching nestlings previously weighing more than the hatch later. This makes it possible for women to prioritize which girls feed on food shortages, although this weight difference is less clear about 12 days into nesting, suggesting that this parent reduction has only a significant effect early in the nestling period. The killing of chicks and eggs sometimes happens when a man is replaced by another man. Infanticide usually does not occur when the clutch is incomplete, because the substitute male then has a chance to fertilize at least one egg. When men arrive during incubation, sometimes infanticide, but other times adopt eggs, because it is possible that some eggs come from surrogate males. If a surrogate male arrives after the chicks hatch, however, infanticide is usually done, although women will sometimes prevent this.
The gender ratios of male turtle boys are biased in women with better conditions, and these men produced by women in better condition are themselves in better condition. This is hypothesized because males have more variability in reproductive success, so it means that women in better condition will produce men in better conditions that may have better reproductive success (more than women with similar conditions).
Growing growth of nesting trees affected their environment. The growth of young nest - aged two to four days - is positively affected by higher maximum temperatures and older ages, and is negatively affected by later hatching dates. In older nests - those nine to eleven days - growth is positively affected, albeit to a lesser extent, by higher maximum temperatures and more abundant insects, and negatively affected, again becoming less of an effect , on the next hatching date. and older age. In terms of thermoregulation, swallowing nesting trees are capable of thermoregulation at 75% capacity compared with adults at an average age of 9.5 days when out of the nest, and from nine to four days when in the nest (depending on size). from its parent). These nestlings generally fly after 18 to 22 days, with about 80% fledging success. As with successful hatching, this value is reduced by unfavorable weather and younger women. For the first year, the swallow tree has an average annual mortality rate of 79%, and a rate of 40% to 60% thereafter. The maximum age recorded for this bird is 12 years.
Feed
The tree swallows HMT 0 to 50 meters (160 feet) above the ground singly or in groups. The flight is a mixture of flapping and gliding. During the breeding season, this is mostly 4 kilometers (2.5Ã, mi) away from the nest site. When it is foraging for nests, though, it usually rises up to 200 meters (660Ã, ft) from the nest, most of it still visible, and feeds at altitudes of up to 12 meters (39Ã, ft). In addition to being caught in flight, insects are sometimes taken from soil, water, vegetation, and vertical surfaces.
Swallow trees eat most insects, with some mollusks, spiders, and fruit. In North America, flies make up about 40% of the diet, with beetles and ants supporting it. If not, the diet is about 90% flies. Seed and berry foods are mainly derived from the Myrica genus, which is primarily taken in all four northern hemisphere seasons except for summer. Crustaceans are also found important in winter diets in a study on Long Island, New York.
Both sexes feed the nestlings, although men feed fewer chicks than females. There are about 10 to 20 feedings per hour. The order of hatching affects how many chickens are fed; the last hatch nestlings (in cases where hatching is asynchronous) tend to eat less than previous hatches. Nestlings closer to the entrance of the nest are also more likely to be fed, as are those who start begging. The food itself consists mostly of insects, with insects in the Diptera, Hemiptera, and Odonata orders that make up most of the food. These insects measure almost 10 millimeters (0.39 inches), but sometimes reach a length of up to 60 millimeters (2.4 inches). In a nest near a lake that is acidified by humans, calcium supplements, especially fish bones, shrimp exoskeleton, shellfish shells, and egg shells, are more important in the diet of nestlings. To get this calcium supplement, the adult bird swallows the journey further than usual; sometimes up to 650 meters (2,130 feet) from the nest.
Parasites and Immunology
Parasites
Swallow trees are susceptible to various parasites, such as the blood parasite Trypanosoma . It is also susceptible to the flea Ceratophyllus idius and fur mites Pteronyssoides tyrrelli , Trouessartia , and (possibly) Hemialges . This may also be caused by the lice of the Brueelia genera and Myrsidea . There is a correlation between the number of ticks in birds and the number of young people they care for. This relationship speculates to be the cause of improved microclimate for ticks due to larger coupling. Nestlings also suffers from parasites, such as the flies of the genus Protocalliphora . This parasite, though, does not seem to have a significant effect on the nest, and is found in most nests. A study published in 1992 found that only 5.5% of variation in mass nestling can be explained by the effects of parasitism.
Immunology
In breeding of female birds, humoral immunocompetence (HIC) correlates inversely with the installation date. This means that, on average, a bird that lays its eggs early has a stronger antibiotic response to the antigen than the bird that lays its eggs later. In addition, swiftlets that are flawed by the clippings generally have a lower HIC. This relationship can be interpreted as supporting the conclusion that a woman who puts earlier earned a higher HIC, but the study authors who found the correlation found this impossible. Instead, they suggest that it shows that better quality women can lie down early because of that quality. The fact that a disabled bird has a higher HIC indicates that the HIC is sensitive to an increase in workload.
In swallowing the tree, some components of the immune system worsen with age. Cell-mediated cell immunity, for example, decreases with age in swallowing female birds. However, a woman's age does not affect the acquired and innate humoral immunity. Because of this immunosenescence (decreased immune function with age), older women infected with the disease can visit their nests less and this can have a more obvious effect on nest growth than infection would be in younger women. In addition, older women tend to lose weight due to infection.
Status
Swallow trees are considered at least of concern by the International Union for Nature Conservation. This is due to a large range of birds of approximately 834,000 square kilometers (322,000 sq./a mi), and its stable population, estimated at about 20,000,000 people. In parts of the United States, this swallow range has expanded to the South, possibly due to land use change, reintroduction of beavers, and boxes mounted for blue birds. Swallowing trees are a negative impact by forest clearance, and there is a documented impact of swamp reduction, which reduces habitat available for winter. Swallow trees also had to compete for nest sites with common starlings and sparrows, both of which were introduced to North America. Acid rain that moisturizes the lake can force it to go for a relatively long distance to find calcium-rich items, and that can cause it to eat some plastics. Other chemicals, such as pesticides and other pollutants, can become highly concentrated in eggs, and PCBs are associated with coupling coupling neglect.
References
External links
- Swallowing tree - Tachycineta bicolor - USGS Counterfeit Identity Information Center
- Swallow species account - Cornell Lab of Ornithology
- How to create and manage a nest box project to swallow a tree
- "Trees swallowing media". Bird Bird Collection .
- Swallow photo gallery in VIREO (Drexel University)
- Tree seedlings, borealforest.org
Source of the article : Wikipedia
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