Trumpeter birds
| Trumpeter birds | ||||||||||
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Gray winged trumpeter bird ( Psophia crepitans ) |
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| Systematics | ||||||||||
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| Psophiidae | ||||||||||
| Bonaparte , 1831 | ||||||||||
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| Psophia | ||||||||||
| Linnaeus , 1758 | ||||||||||
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The trumpet player birds ( Psophia ) are a genus in the same family of the trumpet player birds (Psophiidae) within the order of Gruiformes (Gruiformes). The genus consists of six very similar, ground-living species , of which only the white-winged trumpeter bird has been researched in more detail. The range of the birds that live in groups, about the size of a chicken, is the tropical rainforest of northern and central South America .
features
anatomy
Trumpeter birds reach a body length of around 49 centimeters and a maximum weight of 1.5 kilograms, the species do not differ from one another in these dimensions. Males of the white-winged trumpeter bird are on average 10% heavier than females, whether this sexual dimorphism of weight also exists in the two other species is not known. Due to the compact body shape and the humped profile, trumpeter birds are more reminiscent of hen birds than other related crane birds . The stocky appearance of the body is deceptive, however, since the birds always keep their wings arched and slightly spread apart from the body and cover the body flanks and the very short tail with them. The actual, slender trunk only comes out when the birds lift their wings. On a long, slender and mostly S-shaped neck sits a head that appears small in relation to the body and has large eyes. The strong, roughly head-length beak is slightly bent down and ends in a sharp point. Its shape is reminiscent of the beak of some chicken birds, such as that of the capercaillie .
Like most ground-dwelling birds, trumpeter birds have strong, relatively long legs. Three strong toes point forward, a single, shorter and narrower toe points backwards. As with other crane birds, such as the railing birds , this is a little higher on the leg. Despite their well-developed musculature, the birds with their short, rounded wings are only able to fly over short distances.
Coloration and plumage
All trumpeter birds have predominantly black plumage , their arm feathers and arm covers are lighter in color: gray for the gray winged trumpeter bird , white for the white winged trumpeter bird and iridescent dark green for the green winged trumpeter bird . When the wings are kept in a resting position, the light-colored parts of the plumage form a large, oval spot that covers a large part of the back to the rump and parts of the flanks. Hair-like filaments that are attached to the cover of the arm and are hardly tangled with one another lie loosely on this area. The wing has a relatively large, blue or green metallic shimmering mirror . It is believed that the mirror can provide information about the approximate age of a bird, since it consists to a greater extent of dark, matt-colored feathers in younger trumpeter birds than in older individuals. The head and neck are densely covered by extremely short, black, shiny feathers, on the chest there is a blue or green iridescent spot, depending on the incidence of light, which is formed by short, ruffled feathers. The iris is dark maroon in color. Depending on the species and subspecies, the beak varies in color from bright yellow with a gray tip to completely black or gray. The color of the legs is light to dark gray. The white-winged trumpeter bird is known to undergo permanent moulting, and this is most likely also the case with the other species of the genus.
Move
While searching for food, trumpeter birds move at a speed that roughly corresponds to that of a running person, but when they run, much higher speeds can be reached. As birds living on the ground, they rarely fly and avoid it whenever possible. The birds only fly to get to a place to sleep or nest, and less often to overcome obstacles. Although they can swim, trumpeter birds avoid the water. While running, the body is kept parallel to the ground, the neck is stretched slightly forward and nodding movement with every step.
voice
As birds that enjoy calling, trumpeter birds have a whole range of different vocalizations. The eponymous call of the trumpeter birds sounds less like a trumpet, but is a series of grunting, choppy sounds emitted in rapid succession, which are usually followed by a drawn out, quieter and plaintive " Oh-oh-oh-oh-ooooooooooh ". Every two and a half hours or so, this call is used to defend the territory, both during the day and during the night.
When threatened or frightened, trumpeter birds utter a call similar to the territorial call, but shrill and sharper-sounding, in which the " ooooooh " is missing at the end. Chicks, as well as young birds and adults, are able to utter a chirping begging call. This is used during the various social rituals within the group. A bird carrying food in its beak and trying to feed it to a begging bird often emits a nasal sounding " inhh-inhh-inhh-inhh ". This call is made by males and females also in the phase immediately before mating. If a bird detects a snake, it warns the other members of its group by humming a soft tone that sounds like " hm-hm-hm-hm " several times in a row until the attention of all group members is focused on the snake.
distribution and habitat
Trumpeter birds live in areas of dense, pristine tropical rainforest of the Amazon basin in northern and central South America. The species are in part spatially separated from one another by the large rivers of the lowlands. The distribution area of the gray- winged trumpeter bird is north of the Amazon , that of the white-winged trumpeter bird and the ocher-winged trumpeter bird south of the Amazon and west of the Rio Madeira , green-winged trumpeter bird, brown-winged trumpeter bird and olive-winged trumpeter bird occur south of the Amazon and east of the Rio Madeira on. Both higher mountain rainforests up to a height of 750 meters and lowland rainforests and swamp-like areas on the edge of large bodies of water are populated. Areas with light vegetation and a high diversity of fruit-bearing trees are preferred in every habitat . Trumpeter birds also rarely colonize succession areas , but never in secondary forests created by human hands or created after human intervention . During the rainy season , large areas of the habitat can sometimes be flooded.
Territory and range
The territory defended by the groups all year round reaches a size of 58 to 88 hectares, depending on the food supply, the territories of neighboring groups do not overlap and have precisely defined boundaries, which are rarely exceeded. The number of trees in it, which regularly bear fruit even in the dry season, has a major influence on the size of the defended area , as fruit is the main source of food for all trumpeter birds. Trumpeter birds cover an average of 3.7 kilometers during one day.
Way of life
Activity and comfort behavior
At sunrise, the birds move from their roost to the ground and begin with the interaction described under social behavior, before they usually seek out a nearby fruit-bearing tree and begin to eat. Much of the day is spent switching between fruit-bearing trees scattered around the territory. When fruit is in abundance, trumpeter birds spend more time bathing, sunbathing and socializing. In addition to cleaning, the comfort behavior consists of spreading a wing, stretching and folding the neck as well as a slight fluffing of the plumage, usually combined with soft utterances. When dusk begins, the trumpeter birds go to a sleeping place that changes from night to night. This is located on the branches of a tall tree, usually between 8 and 15 meters high, and is reached by flying.
Social behavior
Group size and composition
Trumpeter birds live in highly social, hierarchically organized associations of 3 to 13 individuals. On average, a group consists of seven individuals, of which three birds are usually unrelated males, two birds unrelated females and two young birds of the last brood.
Dominance and submissiveness behavior
The shimmering mirror on the wings apparently serves the members of a group for optical communication while they are eating, and it also seems to play a role in the behavior of the individuals in a group. This behavior, which can be observed in the early morning immediately after sunrise and after leaving the sleeping place, serves to establish and consolidate the hierarchy within a group. Lower-ranking birds crawl with outstretched wings towards higher-ranking birds and emit chirping sounds that resemble those of young birds. The dominant birds respond to the symbolic submission with rapid, fluttering wings. The hierarchy is gender specific, the morning ritual is performed separately by both sexes. After a few minutes the birds finish the ritual and start looking for food together.
Plumage care, feeding and play
During the day, members of a group often groom each other's plumage. This behavior is initiated by the approach of two individuals with bowed heads. One of the two birds, always same-sex, begins to pluck dirt, parasites and other impurities from the plumage of the other's head and neck by opening and closing the beak quickly. The caring bird seems to enjoy this very much, closing its eyes, lowering its head further, relaxing and, as a result, occasionally even losing its balance. When the plumage is finished, the birds change roles.
Another behavior can be observed when food is in abundance, such as when many trees are fruiting at the same time. At these times, individual individuals take food in their beak, raise their wings slightly, cranks up, and strut about. They utter brief calls. Birds of the same sex and juveniles run to the strutting bird, crawl up to it and utter chirping begging sounds. After a few seconds, the food is given to one of the begging birds and is usually eaten immediately; more rarely, the food is given back and then consumed again.
Trumpeter birds often play together. They behave similarly to during territorial battles. They chase each other, but without kicking or chopping, fluttering in the air, attacking leaves, stones and twigs and chirping loudly in the meantime. The game usually only lasts a few minutes.
Territorial and antagonistic behavior
Groups of neighboring territories often perceive each other from a great distance thanks to good hearing. If a group crosses the boundaries of a neighboring territory and the group occupying the area notices this, it runs at high speed towards the invading birds in order to drive them away. If the invading group does not withdraw quickly enough, a fight ensues. The birds fight each other by lowering their heads, lifting their wings a little, spreading their flight feathers towards the ground and finally running towards each other. Only animals of one sex fight against each other. First the birds try to impress each other by flapping their wings and jumping briefly into the air. If the intruding group does not flee after this demonstration, the defending group begins to pick and kick at the intruders with their beaks until they finally flee. In the course of the fight, the animals repeatedly utter the loud, characteristic territorial call. After the invading group has fled, the females and young birds of the association occupying the area join in the territorial call, while the males pursue the fleeing group for a short distance.
After a fight there may be rituals of domination and submission between the groups, occasionally food is exchanged to appease. Above all, low-ranking males sometimes change groups as a result of territorial fights, as they can possibly take a higher position in the hierarchy in the new group. If this fails, the males usually return to their original group after a few days or weeks, which they accept and accept again without any problems.
Trumpeter birds flee running or, less often, in flight when they feel threatened by predators such as ocelots , jaguars or humans. If a member of the group utters a warning call, the birds flee into thick undergrowth and press against the ground, behind stones or tree trunks. In the event of immediate danger, a group flies up with loud shouts and looks for protection on branches and in the treetops. Young birds are protected from predators that are dangerous to them, such as snakes, in that the adult birds attack and drive away the predator with bills and kicks.
Interspecific relationships
Trumpeter birds occasionally act commensalistic and follow, for example, wandering ants when they look for food in large flocks on the forest floor. Small animals that try to escape the ants are captured by the trumpeter birds. Primates that hunt insects in the treetops are chased by the trumpeter birds on the ground as insects regularly fall to the ground. Similarly Tamanduas observed break down the ant and termite nests that escaping animals are eaten.
nutrition
Trumpeter birds feed mostly frugivor , about 90% of their diet consists of fruits of different stages of ripeness. Since the birds are unable to open hard pods or pods of fruits, fruits with a soft exocarp and mesocarp are mainly eaten, for example the fruits of various types of ficus . Small fruits such as berries up to a size of two centimeters are swallowed whole, while the pulp of larger fruits is picked off. If trumpeter birds swallow seeds , these pass largely undamaged through the digestive tract of the birds and are excreted in a germinable state. Therefore, like other fruit-eaters, trumpet birds play an important role in the spread of some plant species. Much of the food ingested is picked up from the ground, fruits are only rarely picked from low bushes. In the tropical rainforest, fruit-bearing trees attract a wide variety of animals, including primates . Trumpeter birds are dependent on these, as the monkeys chop off fruit while climbing in the treetops and throw them on the ground.
Invertebrates and small vertebrates make up about 10% of the diet . These are captured by turning branches and leaves lying on the forest floor with the beak in order to discover animals underneath. Potentially stinging or biting prey animals are crushed with the beak before swallowing or, in the case of ants, rendered harmless by a sting . Trumpeter birds deal with millipedes, which release caustic protective secretions, in a similar way to when they are huddled with ants, they often rub them on their plumage or objects for several minutes until the secretion is removed. During this procedure, birds in a group take turns handing the centipede to be cleaned to each other every few minutes. If trumpeter birds encounter small snakes, these are almost always killed with beak blows and eaten if they are not poisonous. First, however, they are observed by all group members, sometimes for a few minutes, in order to assess the danger posed by the snake. Drinking water is taken from puddles or small watercourses.
Reproduction
The trumpeter bird breeding season begins towards the end of the dry season, so the chicks hatch at the beginning of the rainy season when the food supply increases. Trumpeter birds are cave breeders . There is one brood per year, in the event of a complete brood loss, if the rainy season is not already coming to an end, a second brood can occur. Only about half of the broods are successful.
Pair formation and courtship
The trumpeter birds practice cooperative polyandry that is not very common among birds , i.e. only a few individuals breed within a group, but the other members of the group help with the rearing of the young birds. The dominant female mates with the three highest ranking males in the group.
Already about a month before it begins to lay eggs, the male members of a group make more efforts to care for the female by offering and feeding her food over and over again throughout the day. During this time they stop ritually feeding other group members. In particular, the dominant male doesn't leave the female's side during this time and feeds her constantly. About six weeks before the eggs are laid, the first males begin copulations that are still short, usually only a few seconds . The mating is usually preceded by a short courtship behavior , during which the male walks with his head raised in tight circles around the female, who is lying on its stomach and turns with the male. Occasionally, dances accompanied by vocalizations before mating are reported, but this seems to be due to a confusion with the playing behavior of the birds. During this time, however, the female is still sterile and it is assumed that the copulations are only intended to clarify the right to mate to other group members. The eggs can only be fertilized in the last two weeks before oviposition, during which time only the three highest-ranking males in the group copulate with the female. They try to disturb each other and prevent copulation. Two thirds of the copulations are carried out by the dominant male.
Nest building and nest location
About two and a half months before the eggs are laid, the dominant female and male begin to seek out and inspect potential nesting cavities. During this time, about 10 to 12 nesting sites are examined for their suitability, and about a week before the start of egg-laying, the birds begin to clean the selected nesting cavity. A nest is created at an average height of 11 meters in tree hollows, the white-winged trumpeter bird prefers to use caves in Iriartia palm trees if they are present. Used breeding caves often have a bulge at the lower edge of the cave entrance, which makes it easier for chicks to jump out of the cave after hatching. Together with the dominant female, the dominant male prepares the breeding cave by removing branches, leaves and other disturbing objects from the cave and then lining the floor with a sparse, largely rotten wood.
Clutch and brood
The clutch consists of two to four white eggs with a rough shell and an average of 60 × 48 mm. The eggs are laid every two days. Only after the last egg has been laid does the brood begin.
The dominant female sits on the clutch from sundown until late morning of the next day, only to be replaced by a male for the rest of the day. 75% of the time the dominant male takes on this task, lower-ranking males only sit 25% on the clutch. When the time has come for the male to detach the female on the clutch, the entire group goes to the nest location and waits below the brood cavity until the change is complete.
After about four weeks, the young birds hatch within 24 hours. When they flee from the nest , the chicks climb out of the cave the day after hatching and jump onto the forest floor, encouraged by the group waiting on the ground and making calls. After falling more than 10 meters high, the young birds lie motionless on the ground for a brief moment, but get up quickly and begin to beg for food. First of all, the chicks are covered by red-brown dunes , on the head there is a black stripe on the crown, on the back there are some also black stripes along the spine. After about 10 days the wing feathers can be seen, after six weeks the young trumpeter birds are feathered like adult birds and are able to make short flights.
For about three weeks, the young birds are fed by all group members, but above all by the dominant female and the lower-ranking males. From the fourth week onwards, they begin to eat around a quarter of their food independently. At three months of age, the young birds are largely self-sufficient, but continue to beg older group members for food. Fledglings stay with the group for the time being and help raise the brood for the next year before they migrate around one and a half years old and join groups that are further away. This is easier for males than for females, which are initially fought by the established dominant females of other groups.
Eggs, chicks and young birds can fall prey to birds of prey, big cats and snakes, but are protected by the group. Nevertheless, only about half of all clutches hatch chicks, half of all hatched young birds fall prey to predators within the first month of life. Many juveniles are captured at night because, due to their inability to fly, they climb on easily accessible branches at a height of 2 to 3 meters to sleep, where the adult group members cannot protect and warn them.
Systematics
External system
Within the crane birds , the trumpeter birds are placed by most systematics in their own family (Psophiidae). However, it is largely unclear about the degree of relationship to other families of the crane birds. One of the reasons for this is that so far hardly any fossils that can be clearly assigned to the Psophiidae have been found.
According to a suggestion from Cracraft , the closest relatives of the Trumpeter Birds may be Seriemas , Kagu, and Sun Rail . Sibley et al. on the other hand, suggested that the cranes , black-wheeled crane and rush-claws be regarded as the closest related to the Psophiidae. The latest phylogenetic studies seem to support this view, but the exact relationship of the Psophiidae within the suborder Grues regarded as monophyletic remains unclear.
Internal system
The genus Psophia contains six species with a total of seven subspecies. The division probably took place in the Pleistocene , after populations were separated from one another by changes in river courses and regional, climatic-related regression of the rainforest. Today the occurrences of the species are separated by the rivers of the lowlands. The individual subspecies are differentiated on the basis of small differences in the plumage color and the spatial separation by tributaries of the large rivers. Occasionally, gray-winged and white-winged trumpeter birds are viewed as one species, but this view is rejected by the vast majority of systematics.
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Gray winged trumpeter bird ( Psophia crepitans ):
- Subspecies:
- P. c. napensis : Southeast Colombia , eastern Ecuador to northeast Peru and the extreme northeast of Brazil, north of the Amazon and west of the Rio Negro . Breast feathers shimmer violet, otherwise very similar to P. c. crepitans
- P. c. crepitans : South-eastern Colombia, eastern and southern Venezuela , Guyana and French Guiana, and northern Brazil, north of the Amazon and east of the Rio Negro. Greenish shimmering patch on the chest, dark gray patch on the back with an orange-brown band in the upper quarter. Gray-yellow beak with a dark tip.
- Subspecies:
- White-winged Trumpeter Bird ( Psophia leucoptera): Eastern Peru, Central, and Western Brazil. South of the Amazon and Solimóes, west of the Rio Madeira. In addition, northeastern Bolivia. White spot on the back, light beak.
- Ocher-wing trumpeter bird ( Psphia ochroptera): Northwest Brazil, north of the Amazon or Solimões , west of the Rio Negro. Similar to P. c. napensis , but has a completely orange spot on the back and a black beak.
- Green-winged Trumpeter Bird ( Psophia viridis ) : Central Brazil south of the Amazon, between Rio Madeira and Rio Tapajós . Striking blue shimmering mirror, the green patch on the back covers almost the entire back and merges seamlessly into the black plumage on the shoulder area. Gray and yellow beak.
- Olive-winged Trumpeter Bird ( Psophia dextralis ): Eastern to central Brazil, south of the Amazon between Rio Tapajós and Rio Tocantins . Back spot inconspicuously green-brown, beak colored black.
- Brown-winged Trumpeter Bird ( Psophia obscura ): Northeastern Brazil to Pará , south of the Amazon and east of the Rio Tocantins. The back spot is dark brown and can hardly be distinguished from the surrounding black plumage.
Trumpeter birds and humans
etymology
Depending on the region, trumpeter birds are called differently by the local population. The birds in Surinam are called “ kamee-kamee ”, which translates as “camel 's back ”, which refers to the hunched appearance of the birds. " Kamee " comes from the Dutch word " Kameel ", for "camel". In large parts of Brazil the trumpeter birds are called " Jacamim ", which means "bird with a small head" in the Tupi language . In the state of Pará in northeastern Brazil and in French Guiana , the common name is “ Agami ”, as the trumpeter birds are also called in French . Both the German name and the English name "Trumpeter" are derived from "Oiseau trompette", a name for the trumpeter bird, which the French naturalist La Condamine derived from the Spanish " trompetero " in the 18th century . Spanish settlers in the Amazon basin called the birds " trumpetero " because of their loud calling, which evidently reminded them of the sound of a trumpet. Carl von Linné named the genus Psophia after the Greek word “ psophos ”, which is synonymous with the French “ péter ” and thus “fart”. This designation referred to the false assumption that the anus of the trumpeter birds is used to produce sound.
myth
The people in the range of the trumpeter birds know the animals mainly from the legends of some indigenous peoples . They believe that trumpeter birds are among their ancestors. Other legends say that the trumpeter birds learned their call from the roosters of the domestic fowl or that tame trumpeter birds as well as herding dogs bring back runaway livestock to the herd.
The myth persisted into the 20th century that the loud call of the trumpeter bird was not generated by the vocal head , but instead by the anus . Linnaeus was already caught up in this misconception, and although naturalists contradicted this theory as early as the 18th century, it was reported back in 1908.
Trumpeter birds as pets and in zoos
Trumpeter birds are regularly kept as pets by locals. For this purpose, eggs are either removed from the nest and pushed under a brooding domestic chicken, or very young birds are caught. The chicks, when raised by hand, become extremely tame as they are imprinted on people and see known people as members of their "group". These birds recognize their owners as dominant and regularly perform the ritual of submissiveness, which is described under social behavior, they also beg for food, offer food and ask for plumage care.
Trumpeter birds kept as pets are often added to groups of domestic chickens as "watch birds". When unknown people or potential predators approach, or when there is interference, the birds utter a warning call. The keepers also appreciate the ability of the trumpeter birds to warn of snakes.
Trumpeter birds have been kept in zoos since the 19th century, but are seldom seen there due to their nutritional requirements, susceptibility to disease and the lack of breeding success. The Seattle Zoological Garden has had a few successful gray-winged trumpeter bird rearing, as has the San Diego Zoo . The Ebbs Rarities Zoo has been breeding gray-winged trumpeter birds regularly for several years.
hunt
Bird meat has always been valued as extremely tasty. The appearance in groups and the strong cohesion within the associations also make it a popular prey, which means that several birds can often be shot at once. Hunters locate nearby trumpeter birds by imitating their territorial call and locating the responding group. At night, the birds sitting on the roost are blinded by strong light, the disoriented animals are easy prey. In the past, the locals mainly used slings to hunt down the birds, but now rifles are usually used.
Threat and protection
The IUCN lists one species as “ not endangered ”, two as “potentially endangered” , one as “endangered” , one as “ critically endangered” and the brown-winged trumpeter bird as “critically endangered” . Since trumpeter birds only colonize intact primary forests, the increasing clearing of the rainforest is a threat to the populations. To make matters worse, the trumpeter birds have relatively low population densities due to their large territories and losses, for example through increasing hunting, can only be compensated with difficulty. Another problem is the decline in numbers of many primates. Without the monkeys searching for fruit in the treetops, fewer fruits fall on the forest floor, which is why trumpeter birds find less and less food. In the vicinity of newly created human settlements, the populations of trumpeter birds usually decline sharply within a very short time due to the heavy hunting. Large, stable populations are only available in large protected areas, as well as in still undeveloped and inaccessible areas of the rainforest.
Web links
- Trumpeter Birds in the Internet Bird Collection
- Birdlife International factsheet, 2007
- Psophia on the IUCN Red List of Endangered Species .
- xeno-canto: Sound recordings - Gray-winged Trumpeter ( Psophia crepitans )
- xeno-canto: Sound recordings - Pale-winged Trumpeter ( Psophia leucoptera )
- xeno-canto: Sound recordings - Dark-winged Trumpeter ( Psophia viridis )
swell
Much of the information in this article is taken from:
- Josep del Hoyo , Andrew Elliot, Jordi Sargatal: Handbook of the birds of the world. Volume 3: Hoatzin to Auks. Lynx Edicions, Barcelona 1996, ISBN 84-87334-20-2 .
The following sources are also cited:
- ↑ N. Seddon, JA Tobias, A. Alvarez: Vocal communication in the pale-winged trumpeter (Psophia leucoptera): repertoire, context and functional reference . In: Behavior 2002, Vol. 139, No. 10, pp. 1331-1359. Web link: PDF ( Memento of the original dated January 6, 2009 in the Internet Archive ) Info: The archive link was inserted automatically and has not yet been checked. Please check the original and archive link according to the instructions and then remove this notice.
- ↑ PT Sherman, PK Eason: Size Determinants in Territories with Inflexible Boundaries: Manipulation Experiments on White-Winged Trumpeters' Territories . In: Ecology 1998, Vol. 79, No. 4, pp. 1147-1159. Web link: [1]
- ↑ C. Érard, M. Théry, D. Sabatier: Régime alimentaire de Tinamus major (Tinamidae), Crax alector (Cracidae) et Psophia crepitans (Psophiidae) en forêt guyanaise . In: Gibier Faune Sauvage 1991, No. 8, pp. 183-210
- ↑ PA Jansen, PA Zuidema: Logging, seed dispersal by vertebrates, and natural regeneration of tropical timber trees . In: The Cutting Edge: Conserving Wildlife in Logged Tropical Forests 2001, Chapter 3. Weblink: http://www.earthscape.org/r3/ES14447/fimb_ch3.pdf Genealogie, Dead Link | date = 2018-03 | archivebot = 2018 -03-26 00:02:28 InternetArchiveBot | url = http: //www.earthscape.org/r3/ES14447/fimb_ch3.pdf}} (registration required)
- ↑ M. Fenner, P. Jordano: Seeds: The Ecology of Regeneration in Plant Communities 2000. Chapter 6, Fruits and Frugivory. Web link: [2]
- ^ A b C.L. Horning, M. Hutchins, W. English: Breeding and management of the common trumpeter (Psophia crepitans) . In: Zoo Biology 2005, Vol. 7, No. 3, pp. 193-210. doi : 10.1002 / zoo.1430070302
- ^ A b P. T. Sherman: Breeding Biology of White-Winged Trumpeters (Psophia leucoptera) in Peru . In: The Auk 1995, Vol. 112, No. 2, pp. 285-295. Web link: PDF
- ^ PT Sherman, PK Eason: Dominance status, mating strategies and copulation success in cooperatively polyandrous white-winged trumpeters, Psophia leucoptera . In: Animal Behavior 1995, Vol. 49, No. 3, pp. 725-736. doi : 10.1016 / 0003-3472 (95) 80205-3
- ^ J. Cracraft: Toward a phylogenetic classification of the recent birds of the world (Class Aves) . In: The Auk 1981, No. 98, pp. 681-714.
- ^ Charles G. Sibley, Jon E. Ahlquist, Burt L. Monroe: A Classification of the Living Birds of the World Based on Dna-Dna Hybridization Studies. In: The Auk 1988, Vol. 105, No. 3, pp. 409-423.
- ^ MG Faina, C. Krajewskib, P. Houde: Phylogeny of "core Gruiformes" (Aves: Grues) and resolution of the Limpkin-Sungrebe problem . In: Molecular Phylogenetics and Evolution 2007, Vol. 43, No. 2, pp. 515-529.
- ↑ Trumpeters (Psophiidae). Retrieved September 15, 2019 .
- ^ The IUCN Red List of Threatened Species. Retrieved September 15, 2019 .
- ↑ E.-T. Hume, A. Lee, C. Fothergill, M. Hammer: Expedition report: Surveying monkeys, macaws and other wildlife of the Peru Amazon . Biosphere Expeditions 2005, Weblink: PDF ( Memento from May 23, 2006 in the Internet Archive )
