European red-throated caracara
| European red-throated caracara | ||||||||||||
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European red-throated caracara ( Ibycter americanus ) |
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| Systematics | ||||||||||||
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| Scientific name of the genus | ||||||||||||
| Ibycter | ||||||||||||
| Vieillot , 1816 | ||||||||||||
| Scientific name of the species | ||||||||||||
| Ibycter americanus | ||||||||||||
| ( Boddaert , 1783) |
The European red-throated caracara ( Ibycter americanus , syn .: Daptrius americanus ) is a species of bird from the falcon-like family and the vulture falcon subfamily . He is the only representative of the thus monotypical genus Ibycter . The species predominantly inhabits moist tropical and subtropical forests and forest edges in Costa Rica and large parts of South America. Red-throated caracaras are highly specialized in their diet. The main food is the larvae and eggs of social wasps and - less importantly - bees, which build their nests freely hanging in trees. The species has been considered harmless despite a significant reduction in the area since the mid-1970s.
description
Red-throated caracaras are medium-sized and slender, but not very elegant-looking birds. The quite long wings, like the long tail, are rounded at the ends. The head is small and the face, like many members of the subfamily Polyborinae, is bare. The beak is quite small and the upper beak is barely curved, overall the beak is more like that of chicken birds . The legs are short.
With a body length of 43 to 56 cm and a wingspan of 96 to 124 cm, the species is about the size of a common buzzard . The reverse sex dimorphism in terms of body size is low in this species, males reach an average of about 96% of the body size of the females. The area of overlap in body measurements between the sexes is therefore large. Males have a wing length of 318-418 mm; Females measure 331-420 mm. Regarding body weight, however, the sexual dimorphism is apparently significantly larger, males weigh 510–570 g; Females 560-770 g.
Like all representatives of the Polyborinae, the red-throated caracaras show no sexual dimorphism in terms of coloration. Colored ( adult ) birds are almost a single color, glossy black. Only the lower abdomen, leg fletching and tail-coverts are sharply contrasting white, and the rear sides of the head are dashed gray-black. The bare face and throat are red, the wax skin is blue-gray. The legs are orange-red, the claws black. The beak is yellow with a more gray base. The iris is reddish brown to red.
Young birds are very similar to adult birds. Overall, the plumage is less shiny, the face is paler in color and slightly more feathered, the dotted lines on the sides of the head are hardly present. The iris is brown.
Vocalizations
The calls are very loud and noisy like “uh-uh-uh-uh” or screeching loudly and are often uttered by several members of a group at the same time. At a distance, the calls are reminiscent of a troop of macaws .
distribution and habitat
The distribution area of the red-throated carakara today only includes the south of Costa Rica and large parts of northern South America; to the southwest the area extends into the south of Brazil. The species was distributed over large parts of Central America from southeast Mexico to Costa Rica and further in the south and west of Ecuador until the mid-1970s, the northern limit of distribution has since shifted a total of about 1500 km to the south.
The species predominantly inhabits moist tropical and subtropical forests and forest edges, neighboring plantations and older secondary forests. The species is also found locally in dry deciduous forests and in the Brazilian Cerrado , red-throated caracaras inhabit the dense vegetation with stunted trees. The species occurs up to an altitude of 1500 m.
Subspecies
Some authors recognize two to three subspecies, which, however, differ only in size from the nominate form and, according to Ferguson-Lees and Christie, represent rather clinical extremes of this nominate form.
hikes
Migrations are not known, the animals are apparently present in their territories all year round.
Hunting style and diet
Foraging is mostly done in groups that search the lower tops of the trees and the lower and middle layers of the trees, while one or two birds presumably stay higher up in the trees as guardians. The animals are often accompanied by other bird species, for example parrots, toucans , woodpeckers, cotingas and frontal birds ( Psarocolius sp.).
Red-throated caracaras are highly specialized in their diet. The main food is the larvae and eggs of social wasps and - less importantly - bees, which build their nests freely hanging in trees. In a study in French Guiana , these made up 74% of the diet. Most of the nests attacked by the red-throated caracaras have a diameter of less than 20 cm, much larger nests are rarely attacked. The birds tear holes in the nests with their bills and then stick their heads in to pull out pieces of honeycomb. The wasps and bees are apparently unable to sting the birds effectively and keep their distance from the attacking bird. It is believed that the red-throated caracaras provide a chemical repellent to repel wasps and bees.
In addition, be Imagines of wasps and bees, caterpillars, various other arthropods , turtle eggs and various fruits eaten.
Reproduction
Many aspects of reproduction are so far unknown. The courtship apparently consists exclusively of calls and the handing over of prey, behavior typical for other falcon-like such as circling over the breeding ground or common flying games have not been observed so far. Of the nests found so far, one was in French Guiana in the dense jungle at a height of 22 m in a densely entwined tree, two more in southeastern Peru and southwestern Brazil were probably rather untypical in single trees, one of which was in a large tree hollow.
Representative information on the breeding season and the frequency of breeding are not available either. Birds in breeding condition were found in Panama in late May and in Colombia on July 11th. The only known clutch to date comprised two or three eggs. A nest with nestlings was found in the southwest of Brazil in January. Information on the incubation period, the number of nestlings and the nestling time is not yet available. The nests are defended by several members of the troop and the nestlings are also fed by different members of the troop. Individual fledglings that were still being fed were observed in French Guiana in October and in the Amazon region of Brazil in January.
The only group of red-throated caracaras in French Guiana that has been observed over a long period of time has only successfully brooded twice in five years.
Existence and endangerment
The disappearance of the species from almost all of Central America is primarily due to the destruction of the primeval forests in this area. However, the species has also disappeared from areas where the jungle remained untouched. The complex social structure and the apparently very low level of reproduction probably play a role in the decline of the species.
There is no reliable information on the size of the world population, Ferguson-Lees & Christie assume a total population of several 100,000 birds. The IUCN classifies the species as harmless ( "least concern" ) for 2008 due to its still very large distribution area of around 8.1 million km² .
swell
Individual evidence
- ^ J. Ferguson-Lees, DA Christie: Raptors of the World. Christopher Helm, London 2001, ISBN 0-7136-8026-1 : p. 798
- ↑ J.-M. Thiollay: Foraging, home range use and social behavior of a group-living rainforest raptor, the Red-throated Caracara Daptrius americanus. Ibis 133, No. 4, 1991: pp. 382-393. doi : 10.1111 / j.1474-919X.1991.tb04586.x
- ^ A. Whittaker: Nesting records of the genus Daptrius (Falconidae) from the Brazilian Amazon, with the first documented nest of the Black Caracara. Arajuba 4, 1996: pp. 107-109. Full text as pdf ( memento of the original from October 30, 2010 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.
- ^ A. Whittaker: Nesting records of the genus Daptrius (Falconidae) from the Brazilian Amazon, with the first documented nest of the Black Caracara. Arajuba 4, 1996: pp. 107-109. Full text as pdf ( memento of the original from October 30, 2010 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.
- ↑ J.-M. Thiollay: Foraging, home range use and social behavior of a group-living rainforest raptor, the Red-throated Caracara Daptrius americanus. Ibis 133, No. 4, 1991: pp. 382-393. doi : 10.1111 / j.1474-919X.1991.tb04586.x
- ^ J. Ferguson-Lees, DA Christie: Raptors of the World. Christopher Helm, London 2001, ISBN 0-7136-8026-1 : p. 798
literature
- J. Ferguson-Lees, DA Christie: Raptors of the World. Christopher Helm, London 2001: pp. 254-255 and 797-799, ISBN 0-7136-8026-1
Web links
- Ibycter americanus in the Red List of Threatened Species of the IUCN 2008. Posted by: BirdLife International, 2008. Accessed January 31 of 2009.