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Black-necked crane

From Wikipedia, the free encyclopedia

Black-necked crane
Black-necked crane in Ladakh
CITES Appendix I (CITES)[2]
Scientific classification Edit this classification
Domain: Eukaryota
Kingdom: Animalia
Phylum: Chordata
Class: Aves
Order: Gruiformes
Family: Gruidae
Genus: Grus
Species:
G. nigricollis
Binomial name
Grus nigricollis

The black-necked crane (Grus nigricollis) is a medium-sized crane in Asia that breeds on the Tibetan Plateau and remote parts of India and Bhutan. It is 139 cm (55 in) long with a 235 cm (7.71 ft) wingspan, and it weighs 5.5 kg (12 lb). It is whitish-gray, with a black head, red crown patch, black upper neck and legs, and white patch to the rear of the eye. It has black primaries and secondaries. Both sexes are similar. Some populations are known to make seasonal movements. It is revered in Buddhist traditions and culturally protected across much of its range. A festival in Bhutan celebrates the bird while the Indian union territory of Ladakh has designated it as the state bird.[3][4]

Description

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A black-necked crane at the International Crane Foundation

This medium-sized crane is mostly grey with a black head and neck. The lores and crown are naked and dull red. A small patch of white feathers are present below and behind the eye. The tail is black and makes it easy to distinguish at a distance from the similar looking common crane which has grey tail.[5]

Distribution and habitat

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Copy of an illustration in Nikolai Przhevalsky's work where he gave the species its binomial name
From Phobjikha Valley, Bhutan
Black necked crane in Ladakh

The black-necked crane summers mainly in the high-altitude Tibetan Plateau. The breeding areas are alpine meadows, lakeside and riverine marshes and river valleys. They also make use of barley and wheat fields in these areas. Wintering areas tend to be in sheltered valleys or lower altitudes. The largest populations are in China with smaller numbers extending into Vietnam, Bhutan and India.[6] Small populations have been noted in northern Sikkim.[7] A small group of 20 to 40 was once known to regularly visit the Subansiri area in the Apa Tani valley[8] until 1975,[9] and vagrants have been recorded in Nepal.[10]

In 1991, an estimated 600 to 900 cranes inhabited the Hongyuan-Ruoergai Plateau, Sichuan, China, making it the most crucial breeding and summering area for the cranes at that time.[11] According to a 2013 survey, the total crane population in the Zoigê Marsh was 893.[12]

In 1996, there were about 4,000 of the birds, most of whom spent their winters in Tibet in the valleys of the Nyanga, Lhasa and Pengbo rivers and the middle reaches of the Yarlung Tsangpo.[13] The Hutoushan Reservoir in the Pengbo valley is an important winter resting place, with a 96 square kilometres (37 sq mi) Linzhou Black-necked Crane Preservation Zone established in 1993.[14] By 2018, Lhünzhub County's population of black-necked cranes had exceeded 2,100. The largest colony of black-necked cranes consisted of 400 to 500 individuals. [15][16]

Black-necked cranes also winter in small numbers in two valleys of western Arunachal Pradesh, India. These are Sangti and Zemithang.[17][18][19]

Behaviour and ecology

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Black-necked cranes forage on the ground in small groups, often with one bird acting as a sentinel. In winter, the groups arrive and leave the feeding grounds together, but may split into family groups, each group keeping their own small feeding territories in a big marshes or fields.[9] They spend nearly 75% of the day foraging with peak feeding in the early morning and late afternoon.[6] While foraging, they keep walking and they also walk long distances between the feeding spots. In this manner, they cover several kilometers a day while foraging.[20] They feed on the tubers of sedges, plant roots, earthworms, insects and other invertebrates, frogs and other small vertebrates. They may also feed on fallen grains of barley, oats and buckwheat and will sometimes dig up and feed on potatoes, carrots and turnips.[6][21] Their loud trumpeting calls are similar to those of other cranes.[5]

A 1938 photograph of a flock in the Brahmaputra valley

These birds are very wary, but in some areas they are accustomed to the local people who do not disturb them. These cranes appear to be able to distinguish people in traditional dress and are especially wary of others.[20]

100 odd of this species come to India every year for breeding. Photograph taken at Tso Kar, Ladakh, India.

Like many other crane species, they are believed to form long-lasting pair bonds and dancing displays are made during the breeding season. The breeding birds are territorial and will chase away any intruders of the same species immediately, though they are generally tolerant of other species.[20] The nest site is usually a pre-existing mud island inside a large shallow wetland, sometimes shared along with bar-headed goose. The nest varies from a scantily lined scratch in the ground to a structure made of grass, rushes and weeds with a depression in the centre, sometimes the eggs laid directly on the grass without any structure.[22][23] Eggs are laid mainly in May and June. One or two eggs.[5][24] The birds are relatively more wary when the young ones are small. Till the time when the young ones are able to fly, the family kept moving around the nesting location, but later the family started traveling far and wide in the course of a day. Though the young ones are able to forage independently, usually they accompany the parents during foraging. Short, subdued nasal "kurrr" calls are used by the family to keep in contact and also by adults to indicate availability of food to juveniles. The adults were found to feed the young ones mainly with fish in Ladakh, adults fishing like herons.[20]

Status and threats

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A couple of black-necked Tibetan cranes spotted in 2013 near Yamdrok Lake, Tibet Autonomous Region

The estimated population of the black-necked crane was between 10,070 and 10,970 individuals as of 2013.[12] These birds are legally protected in China, India and Bhutan. However, habitat modification, drying of lakes and agriculture are threats to the populations. In many areas, dogs belonging to herders are a major threat to young birds. An incident of leopards preying on the roosting cranes during the night has been recorded from the Phobjika valley of Bhutan.[25] Despite protections, hunting continues to be a problem in parts of China and India.[26] In Bhutan, collisions with power lines have been another cause of mortality in some areas.[1][27] Eggs may also be preyed on by ravens that may use the opportunity provided when humans disturb the parents.[6] The drying of wetlands can cause increased accessibility of the nests leading to predation while a rise in the water level can submerge nests.[28] Loss and degradation of habitat are the main threats facing the black-necked cranes. The problems are most serious in the wintering areas, where wetlands are extensively affected by human activity including irrigation, dam construction, draining, and grazing pressure. In Tibet, widespread changes in traditional agricultural practices have reduced the availability of waste barley and spring wheat.[28]

Populations in Bhutan are well protected both culturally and legally although some disturbance from tourism exists.[29]

The black-necked crane is evaluated as near threatened on the IUCN Red List of Threatened Species.[1] It is listed on Appendix I of CITES.

Parasites

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As all wild birds, black-necked cranes have a number of parasites. Modern parasitological studies are done with non-invasive means, i.e. without harming or killing. A 2024 study, based on metabarcoding of bird feces, found that black-necked cranes from the Dashanbao Black-necked Crane National Nature Reserve, China, harboured at least eight species of helminth parasites and three of protozoan parasites, and were carrying free-living amoebae.[30]

See also

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References

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This article incorporates text from the ARKive fact-file "Black-necked crane" under the Creative Commons Attribution-ShareAlike 3.0 Unported License and the GFDL.

  1. ^ a b c BirdLife International (2020). "Grus nigricollis". IUCN Red List of Threatened Species. 2020: e.T22692162A180030167. doi:10.2305/IUCN.UK.2020-3.RLTS.T22692162A180030167.en. Retrieved 19 November 2021.
  2. ^ "Appendices | CITES". cites.org. Retrieved 14 January 2022.
  3. ^ Khajuria, Sanjay (1 September 2021). "Snow leopard, Black necked crane declared state animal and birds in Ladakh". The Times of India.
  4. ^ "Ladakh declares snow leopard its state animal, black-necked crane state bird". The Statesman. 1 September 2021.
  5. ^ a b c Ali, S & S D Ripley (1980). Handbook of the birds of India and Pakistan. Vol. 2 (2nd ed.). Oxford University Press. pp. 139–140.
  6. ^ a b c d Collar, NJ; AV Andreev; S Chan; MJ Crosby; S Subramanya; JA Tobias, eds. (2001). Threatened Birds of Asia (PDF). BirdLife International. pp. 1198–1225. Archived from the original (PDF) on 22 July 2011.
  7. ^ Ganguli-Lachungpa, Usha (1998). "Attempted breeding of the Blacknecked Crane Grus nigricollis Przevalski in North Sikkim". J. Bombay Nat. Hist. Soc. 95 (2): 341.
  8. ^ Betts, FN (1954). "Occurrence of the Blacknecked Crane (Grus nigricollis) in Indian limits". J. Bombay Nat. Hist. Soc. 52 (3): 605–606.
  9. ^ a b Sekhar Saha, Subhendu (1978). "Blacknecked Crane in Bhutan and Arunachal Pradesh - A survey report for January–February 1978". J. Bombay Nat. Hist. Soc. 77 (2): 326–328.
  10. ^ Rossetti, John (1979). "Blacknecked Crane, Grus nigricollis, seen at Begnas Tal, near Pokhara, Nepal". J. Bombay Nat. Hist. Soc. 76 (3): 513–514.
  11. ^ Scott, D. A. (September 1993). "The Black-Necked Cranes Grus Nigricollis Of Ruoergai Marshes, Sichuan, China". Bird Conservation International. 3 (3): 245–259. doi:10.1017/S0959270900000939. ISSN 1474-0001.
  12. ^ a b Zheng-Quan, JIANG (December 2014). "四川若尔盖湿地国家级自然保护区黑颈鹤种群数量及繁殖" [Numbers and breeding success of Black-necked Cranes (Grusnigricollis) at Ruoergai Nature Reserve, Sichuan Province]. Zoological Research (in Chinese). ISSN 2095-8137.
  13. ^ Meine, Curt; Archibald, George (1 January 1996). The Cranes: Status Survey and Conservation Action Plan. IUCN. p. 187. ISBN 978-2-8317-0326-8.
  14. ^ Zhang, Hao (16 December 2013). "Black-necked crane ends winter migration in Lhasa". CNTV. Archived from the original on 13 February 2015. Retrieved 13 February 2015.
  15. ^ "探访黑颈鹤迁徙越冬情况 越冬为啥偏爱林周？". 中国西藏新闻网 (in Chinese). 11 November 2023. Retrieved 4 September 2024.
  16. ^ "林周县：绿化河谷为黑颈鹤筑"暖"巢_西藏自治区人民政府". 西藏政务服务网. 8 May 2019. Retrieved 4 September 2024.
  17. ^ Choudhury, A.U. (2000). The Black-necked Crane in Arunachal Pradesh. The Twilight 2(2 & 3):31-32.
  18. ^ Choudhury, A.U. (2008). In the valley of cranes. Sanctuary Asia 28(5): 78–80.
  19. ^ Choudhury, A.U. (2009). The crane valleys of India and Bhutan. Environ 10 (2): 10–15.
  20. ^ a b c d Narayan, Goutam; Akhtar, Asad; Rosalind, Lima; D'Cunha, Eric (1986). "Blacknecked Crane (Grus nigricollis) in Ladhak - 1986". J. Bombay Nat. Hist. Soc. 83 (4): 180–195.
  21. ^ Mary Anne Bishop; Li FengShan (2002). "Effects of farming practices in Tibet on wintering Black necked Crane (Grus nigricollis) diet and food availability". Biodiversity Science. 10 (4): 393–398. doi:10.17520/biods.2002054.
  22. ^ Pfister, Otto (2005). "Ladakh: 26 May—26 June 2004". Indian Birds. 1 (3): 57–61.
  23. ^ Baker, ECS (1929). The Fauna of British India, Including Ceylon and Burma. Birds. Volume 6 (2nd ed.). Taylor and Francis, London. pp. 52–53.
  24. ^ Baker, EC Stuart (1928). "The game birds of the Indian Empire. Vol 5. the waders and other semi-sporting birds. Part 6". J. Bombay Nat. Hist. Soc. 32 (4): 617–621.
  25. ^ Tshering Choki; Jigme Tshering; Tshewang Norbu; Ute Stenkewitz; Jan F. Kamler (2011). "Predation by leopards of Black-necked Cranes Grus nigricollis in Bhutan" (PDF). Forktail. 27: 117–119. Archived from the original (PDF) on 4 March 2016. Retrieved 13 March 2014.
  26. ^ Archibald, George W.; Meine, Curt D.; Kirwan, Guy M. (4 March 2020). "Black-necked Crane (Grus nigricollis)". Birds of the World. doi:10.2173/bow.blncra1.01. Retrieved 26 February 2024.
  27. ^ Chandan, P.; Gautam, P. & Chatterjee, A. (2006). "Nesting sites and breeding success of Black-necked Crane Grus nigricollis in Ladakh, India". In G.C. Boere; C.A. Galbraith & D.A. Stroud (eds.). Waterbirds around the world (PDF). The Stationery Office, Edinburgh, UK. pp. 311–314.
  28. ^ a b Hussain, SA (1985). "Status of Blacknecked Crane in Ladakh - 1983 problems and prospects". J. Bombay Nat. Hist. Soc. 82 (3): 449–458.
  29. ^ Chacko, RT (1993). "Blacknecked Cranes wintering in Bhutan". Newsletter for Birdwatchers. 33 (2): 23–25.
  30. ^ Yu, Mengshi; Li, Wenhao; He, Xin; He, Guiwen; Yao, Yonfang; Wang, Yuanjian; Shao, Mingcui; Xiong, Tingsong; Xu, Huailiang; Zhao, Junsong (2024). "Metabarcoding of protozoa and helminth in black-necked cranes: a high prevalence of parasites and free-living amoebae". Parasite. 31: 28. doi:10.1051/parasite/2024028. ISSN 1776-1042. PMC 11141520. PMID 38819296. Open access icon
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