Sichuan strangler
| Sichuan strangler | ||||||||||||
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| Systematics | ||||||||||||
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| Scientific name | ||||||||||||
| Lanius giganteus | ||||||||||||
| Prschewalsky , 1887 |
The Sichuan shrike ( Lanius giganteus ) is an almost hay-sized species of bird from the genus Lanius within the family of stranglers (Laniidae). It was only separated from L. sphenocercus in 2016 and placed in species rank and has been the largest species of this bird genus ever since. Males and females of this mighty, sharply contrasting black-white-gray songbird are identical in appearance and cannot be distinguished from one another by field ornithology. It is significantly darker than the wedge-tailed shrike, its wings and tail are less white than the latter and its black face mask is connected frontally over the base of the beak. Name-giving in the Latin epithet is its size (Greek: γιγαντος = huge, very large). The Sichuan shrike is a high mountain species that occurs in some central and southern Chinese provinces mostly near the tree line at altitudes over 3000 meters. As far as we know, he is largely a resident . The Sichuan shrike is probably also an opportunistic ambulance hunter who defies large insects and various vertebrates such as small rodents , songbirds , amphibians and reptiles . Due to its high alpine habitat, birds and small mammals will predominate in the winter months.
L. giganteus belongs to the species group of the Great Gray Shrike; the species is monotypical . The IUCN is currently (end of 2018) assessing the population of the species with LC (= least concern).
As of the end of 2018, there were no scientific studies on this species; their distribution limits are also largely unknown. Detailed biological information can therefore not be given. Due to the close relationship to the better researched sister species Lanius sphenocercus , however, it can be assumed that many of the information collected for this species also apply to Lanius giganteus . This could particularly apply to the sections food composition and breeding biology , which cannot be presented here due to a lack of data.
Appearance
The Sichuan shrike measures about 31 centimeters. It is long-winged ( L. sphenocercus : 122 mm; L. giganteus : 138 mm) and long-tailed ( L. sphenocercus : 139 mm; L. giganteus : 166 mm) than the wedge-tailed shrike. The average body weight of both sexes is around 80 grams. There is no color dimorphism ; Females are reported to be slightly smaller.
The long tail and the contrasting black-white-gray plumage are characteristic; The wide white wing marks of the hand wings are particularly noticeable in flight , while there is no continuous white band on the arm wings , as in the wedge-tailed shrike, but only isolated, elongated, white spots. Compared to other gray shrike, the species also shows a lot of white in the black wing when sitting, but the proportion of white in the Sichuan shrike is significantly reduced than in the wedge-tailed shrike and the bird appears overall much darker. With regard to Farbtöung and color distribution of Sichuan shrike subspecies resembles lahtora of the Great Gray Shrike passing through the main ridge of the Himalayas spacious separated, southwest of L. giganteus is widespread.
The parting, the nape of the neck, the coat, the upper tail and the rump are slate gray, darkest in the area of the parting and the nape of the neck. The shoulder plumage is white, but this area is narrower, more gradual and therefore less accentuated than in the wedge-tailed shrike. The black face mask is narrowly connected to the upper, frontal base of the beak and runs - widening slightly - to behind the ear covers . It is not bordered white. The wings are black, white at the base of almost all hand and some arm wings; In the seated bird this produces a white wing mirror, while in flight it produces a wide white wing band that extends over the hand wings and tapering towards the arm wings; the wings of the arm show a variable number of irregularly shaped white spots. The tail is very heavily tiered. Its central two control feathers and the inside flags of the adjacent two are completely black, the rest are white with isolated black inclusions. The underside of the body is washed out gray-white. The mighty hooked bill is black, and the legs and irises of the eyes are dark brown to black .
Young birds have a very similar color distribution. They are a little darker than juvenile wedge-tailed shrike and on the underside much more intense than these wavy brownish
distribution and habitat
The Sichuan shrike is a breeding bird in the central and southern Chinese provinces of Qinghai , Gansu , Xizang and Sichuan . The known breeding area extends from northeast to southwest to an extent of about 1000 × 800 km², but is not known in its actual current dimensions. Panov suspects that the Helan Mountains represent a major barrier between the wedge-tailed shrike and Sichuan shrike. The species seems to be widespread but not common anywhere, but could also have been overlooked due to its not very conspicuous behavior and inaccessible habitat. It inhabits high-montane mountain tundra , isolated grassland with bushes and trees near or above the tree line, as well as the mountain pine and rhododendron zone at heights between 3000 and 5200 meters.
Nothing is known about large, regular migrations, but Sichuan shrike are often observed in the winter months southeast of their breeding area in the wintertail shrike. However, the majority of the species is likely to overwinter in the breeding area and only undertake weather-dependent vertical migrations.
Systematics
Lanius giganteus was first described by Nikolai Michailowitsch Prschewalski in 1887. The type specimen comes from the northeasternmost area of the breeding occurrence, an area on Lake Qinghai . It was classified as a subspecies of Lanius sphenocercus . Noticeable differences in habitat preferences, significant differences in color and genetic differences finally led to the HBW splitting the taxon into the two monotypical species Lanius sphenocercus and Lanius giganteus in 2016 , while other authorities such as the IOU emphasize the need for a reassessment, but not yet (As of the end of 2018).
Persistence and Threat
There are neither quantitative nor qualitative assessments of the inventory and the development of the inventory. The breeding area does not seem to be exposed to any immediate threats, a drastic decline in the population has not been reported either regionally or nationally. Therefore, the IUCN assesses the current situation (status at the end of 2018) with LC (= least concern).
literature
- Tony Harris, Kim Franklin: Shrikes & Bush-Shrikes. Including wood-shrikes, helmet-shrikes, flycather-shrikes, philentomas, batises and wattle-eyes. Christopher Helm, London 2000, ISBN 0-7136-3861-3 .
- Josep del Hoyo , Andrew Elliot, Jordi Sargatal (Eds.): Handbook of the Birds of the World. Volume 13: Penduline-Tits to Shrikes. Lynx Edicions, Barcelona 2008, ISBN 978-84-96553-45-3 .
- Norbert Lefranc, Tim Worfolk: Shrikes. A Guide to the Shrikes of the World. Pica Press, 1997, ISBN 1-4081-3505-1 .
- Reuven Yosef, International Shrike Working Group and GM Kirwan: Chinese Gray Shrike (Lanius giganteus). In: J. del Hoyo, A. Elliott, J. Sargatal, DA Christie, E. de Juana (Eds.): Handbook of the Birds of the World Alive. Lynx Edicions, Barcelona 2018 (accessed from: https://www.hbw.com/node/60484 on September 15, 2018).
- Evgenij N. Panov: The True Shrikes (Laniidae) of the World - Ecology, Behavior and Evolution. Pensoft Publishers, Sofia 2011, ISBN 978-954-642-576-8 .
Individual evidence
- ↑ Photo: Sichuan strangler
- ↑ Sichuan Shrike - underside
- ↑ Good photos. Scroll down to the overview. Note: Lanius sphenocercus and Lanius giganteus are mixed; dark birds with little white in the wing belong to giganteus .
- ↑ a b Lanius giganteus in the IUCN Red List of Threatened Species 2016.1. Listed by: BirdLife International, 2016. Retrieved September 19, 2018.
- ^ A b c Evgenij N. Panov: The True Shrikes (Laniidae) of the World - Ecology, Behavior and Evolution. Pensoft Publishers, Sofia 2011, p. 304 ISBN 978-954-642-576-8 .
- ^ T. Harris, K. Franklin: Shrikes & Bush-Shrikes ... 2000, p. 148.
- ↑ a b c d Reuven Yosef & International Shrike Working Group & GM Kirwan: Chinese Gray Shrike (Lanius giganteus) . In: del Hoyo, J., Elliott, A., Sargatal, J., Christie, DA & de Juana, E. (eds.). Handbook of the Birds of the World Alive. Lynx Edicions, Barcelona. (downloaded from http://www.hbw.com/node/1343839 on September 19, 2018).
- ↑ Gray shrike ssp. lahtora
- ^ A b Evgenij N. Panov: The True Shrikes (Laniidae) of the World - Ecology, Behavior and Evolution. Pensoft Publishers, Sofia 2011, p. 305 ISBN 978-954-642-576-8 .
- ^ T. Harris, K. Franklin: Shrikes & Bush-Shrikes ... 2000, p. 147.
- ^ A b Evgenij N. Panov: The True Shrikes (Laniidae) of the World - Ecology, Behavior and Evolution. Pensoft Publishers, Sofia 2011, p. 308 ISBN 978-954-642-576-8 .
- ↑ IOU - Bird List Shrikes