Data Zone
Justification of Red List category
This species is classified as Near Threatened because it has a single small population that is subject to a number of threats that are suspected to be sufficient to cause future declines. It no longer qualifies as Vulnerable as there is no continuing decline. Recent increases in the population have been driven by a reduction in adult mortality through a combination of winter habitat protection and creation, and potentially also a temporary increase in the extent of suitable breeding habitat due to glacial melting.
The species remains Near Threatened as it is plausible that further changes in breeding habitat driven by climate change will reverse the positive recent impact and result in loss of wetlands. In addition there is concern that the impact of existing threats will grow, specifically from feral dogs and human disturbance at breeding sites, and power line collisions and accidental poisoning events during migration and the non-breeding season.
Population justification
The global population is estimated at c.10,000-10,200 individuals in total (Li et al 2014), roughly equivalent to c.6,600-6,800 mature individuals. Recent counts suggest that numbers may be larger than this (Jia et al. 2019) and if these counts genuinely reflect a larger total rather than redistribution then this figure may need to be further revised upwards.
Trend justification
This species's population is presumed to have previously decreased in line with levels of grassland degradation (owing to intensive grazing and pesticide use) and drying up of marshes (due to increased extraction and desertification), and changing agricultural techniques that have reduced the availability of grain in cultivated areas (Li 2019). Recent increases have been observed, attributed to an increase in suitable wetland area within the breeding sites due to rapid glacial melting (Li 2019), but also the creation of a large network of protected sites in the wintering areas, largely in China (Li 2019). The observed increase may partly be due to an increased concentration of birds at fewer sites allowing more accurate census (which may be the case with the recent record counts in Jia et al. [2019]), but it does appear that there has been a genuine increase in the total number of individuals, despite very low recorded breeding success in parts of the breeding range (Li 2019).
Along the Yarlung Tsangpo River Basin, numbers recorded in January 2018 were approximately 30% higher than in 2014 (Jia et al. 2019). This wintering population contains more than half of the global population hence is key to determining rates of change. This rate of change over such a short period is too large to be accounted for by intrinsic rates of population increase, hence it is likely that it at least partly represents a concentration of the wintering population in this flyway at this key site. However, this is likely to also be in conjunction with a real increase in the numbers in this wintering population.
In the eastern wintering population, a pilot payment for wetland ecosystem service project in Dashanbao Protected Area has led to a small increase in the occurrence probability of Black-necked Cranes (Peng et al. 2020). Between 2013-2017 the numbers recorded in Dashanbao have increased from 1,131 to 1,433 individuals (per Peng et al. 2020).
The small number of breeding Black-necked Cranes in Ladakh, India, has been increasing up to 2012, when the largest number (139) was recorded (Chandan et al. 2014, Chandan & Rigzin 2016). However much of this increase is likely due to surveying additional sites, and in the past few years the total number of birds seen is slightly lower (Chandan & Rigzin 2017). This emphasises the importance of continued detailed monitoring during the non-breeding season, as the drivers of the recent increase may be temporary and a number of plausible threats may impact the wider population in the future.
Grus nigricollis breeds on the Qinghai-Tibetan plateau, China, with a small population in adjacent Ladakh, India (Li 2019). The breeding area stretches through mostly continuous plateaus (Li 2019). Ruoergai marshes is thought to hold the largest breeding population, estimated at 2,500 mature individuals (Li 2009). 476 individuals (plus 38 chicks) were recorded in a breeding population survey in the Changtang region of Tibet in 2008 (Li 2019). Repeated surveys at Shenzha in the southern part of the Celin Cuo Black-necked Crane National Nature Reserve found 16 nests in 1991 and 30 nests in 2000. Where breeding sites have been revisited, the recent numbers of breeding pairs have been greater than past reports (Li 2019).
Three isolated wintering populations have been identified at lower altitudes on the Qinghai-Tibet and Yunnan-Guizhou plateaus, China, and Bhutan.
(1) The Eastern population, approximately 4,300 cranes, winters in northeastern Yunnan and northwestern Guizhou Provinces (Li et al. 2014, Yang & Zhang 2014). The majority winter in three national nature reserves on the Yunnan-Guizhou Plateau in this flyway (Dashanbao, Cao Hai and Huize), where 2,469 Black-necked Cranes were counted in 2004 (Li and Yang 2005). Satellite tracking data of eight birds and two colour-banded cranes show birds from Dashanbao and Cao Hai migrate to Ruoergai for breeding (Qian et al. 2009, Wu et al. 1993). Small numbers were once recorded in Vietnam (Bishop & Tsamchu 2007), but this species has not been seen there for over than 30 years.
(2) The Central population winters in northwestern Yunnan, 232-300 individuals (Li et al. 2014, Yang and Zhang 2014, Q. Liu pers. comm. per M. A. Bishop and F. Li. in litt. 2016). Napahai Provincial NR has a stable population of 270 Black-necked Cranes, an increase from less than 100 in the 1980s and before 1997 (Zhao and Yu 2005, Wang et al. 2009). Napahai is the winter home for >90% of Black-necked Cranes in the central flyway.
(3) The Western population, approximately 8,700 individuals (Jia et al. 2019), winters in south-central Tibet and Bhutan with a very few regularly wintering in Arunachal Pradesh, India (Chandan et al. 2014). Along the Lower and Middle Reaches of the Yarlung Tsangpo (Brahmaputra) River Basin in Tibet, a maximum of 8,291 individuals were present in January 2018 (Jia et al. 2019), with the majority using the Middle Yarlung Tsangpo Black-necked Crane NNR. This is an increase on previous counts, 5,559 in 2014 (Zhang et al. 2014), or 6,500 (Yang et al. 2016; fide Jia et al. 2019). and 6,940 in 2007 (Bishop and Tsamchu 2007). Around 550 Black-necked Cranes winter in Bhutan (Phuntsho and Tschering 2014, Royal Society of Protection of Nature [RSPN] 2015), in four wintering sites in Bhutan at Phobjikha, Bumdeling, Khotokha, and Bumthang. Approximately 95% of these occur at the first two sites (Royal Society of Protection of Nature RSPN 2012).Key sites on the birds' migration include the wetlands of the Ruoergai Plateau (China), which serves as a stopover for some individuals and a breeding ground for others, and Gasa (Bhutan), used as a stopover in both autumn and spring (Lhendup and Webb 2009, Qian et al. 2009, Wu et al. 2009).
It breeds in alpine bog meadows and riverine marshes, favouring lacustrine marshes from 2,600-4,900 m. It prefers to nest at large water bodies, at a water depth of around 30 cm: this probably minimises exposure to nest predators. It winters in river valleys and along reservoir shorelines in the vicinity of barley and spring wheat fields. Whilst it prefers breeding in lakes, shallow marshes and meadows are the most important habitat for feeding; its diet consists of roots, tubers, insects, snails, shrimps, fish, frogs, small birds and rodents (Wu et al. 2009; Liu et al. 2010a, 2014).
Threats to the species are primarily connected with the availability of sufficient undisturbed habitat with suitable water levels. There is evidence that Black-necked Cranes are becoming concentrated at fewer sites in wintering locations, with some previously used areas being converted to greenhouse agriculture or for industrial development (Jia et al. 2019). The general increase in the human population in the vicinity of the wetlands the species uses results in higher water demands that can reduce the suitability of key sites, while some have been directly drained for development (Lhendup and Webb 2009). Consequently, development projects that affect the control of water levels must account for the potential impact on the species, which is highly sensitive to water levels due to the threat from mammalian predators. At Dashanbao National Nature Reserve, China, plans to designate the area as a National Park include the relocation of people away from the core zone, however the increasing population of Black-necked Crane demonstrate a clear affinity for human sites due to the provision of waste grain from farming activities (Peng et al. 2020). The relocation plan would lead to the abandonment of farmland, upon which the cranes depend (Kong et al. 2011. Peng et al. 2020, Wu et al. 2020). This represents a potential significant reduction in the number of cranes that this key site can support over winter in the future, which may drive increased adult mortality in this section of the population. Currently, a payment for ecosystem services pilot appears to be contributing towards a steady increase in crane numbers here (Peng et al. 2020). A switch to planting a greater proportion of winter wheat reduces the availability of grain on cultivated land, and Peng et al. (2020) also demonstrate that the species generally avoids ploughed fields.
Climate change appears to be having a positive effect on the species's habitat over recent years (Li 2019), but there is concern that future change will reverse any positive impacts due to drying of breeding sites within the high altitude breeding range of the species (J. Harris in litt. 2007, M. A. Bishop and F. Li in litt. 2016). In some areas water levels may be rising as a result of glacial melt and increased rainfall, but a lot of shallow wetlands used by the cranes are thought to be disappearing due to permafrost degradation (Farrington 2009). For example, in Ladakh, India, Lake Tsomoriri showed a rise in water between 2000-2006 and then the water level started decreasing, whereas Tsokar Basin is shrinking (P. Chandan pers comm. per M. A. Bishop and F. Li. in litt. 2016). These peripheral areas of the population may be the first to demontrate negative impacts and these populations should be carefully monitored.
A small number of birds have been killed after striking power-lines (Li 2002; Li et al. 2012), and wind turbines could prove an additional threat (M. A. Bishop and F. Li in litt. 2016). The threat from power-lines is suspected to be growing following the rapid expansion of local power grids in China: 9 out of 15 juvenile Black-necked Crane fitted with satellite tags were killed in Linzhou, Tibet between 2018-2020 (Y. Guo in litt. 2020). The use of poisoned bait to control rodent pests in breeding areas poses the risk of unintentional posioning (Li 2019). Intensive grazing has caused degradation of grasslands in breeding grounds, with an increase in grazing in wetlands of particular concern (Li 2019). In Bhutan and India, feral dogs have been increasingly observed to take eggs and chicks, and even adults (I. Acharja in litt. 2020, S. Dhumal in litt. 2020, J. Eaton in litt. 2020, L. Visuddha in litt. 2020)
There are additional threats from poorly-regulated tourism to wintering areas, which could cause significant disturbance to large numbers of birds and reduce habitat area and quality through the creation of additional infrastructure such as roads (M. A. Bishop and F. Li in litt. 2016). Fish-farming, peat and firewood collection, river channelisation, industrial pollution and sedimentation, and the construction of roads and fences have resulted in increased disturbance and habitat degradation in Qinghai, Sichuan, Ruoergai and Yunnan, China (Wu et al. 2009, Qiang Liu et al. 2010). Further disturbance at the species's stopover sites arises from the use of the areas as camping grounds by local herders (Qian et al. 2009). The collection of eggs and poaching have been problems in parts of China and India, although the extent of this is currently not thought to be significant.
Conservation Actions Underway
CITES Appendix I and II. CMS Appendix I and II. It is legally protected in China, India and Bhutan; with WWF-India and the Royal Society for the Protection of Nature have been taking a leading role in coordinating conservation work for Black-necked Cranes in India and Bhutan, respectively (M. A. Bishop and F. Li in litt. 2016). A Black-necked Crane Conservation Network was formed in China in 2006, and long-term cooperation exists between partners (such as Kunming Institute of Zoology of the Chinese Academy of Sciences, the Tibet Plateau Institute of Biology, the National Bird Banding Center of China and the International Crane Foundation) to help conserve this species (M. A. Bishop and F. Li in litt. 2016). Major breeding and wintering areas are protected in China, covering a total of 89,073 km2 (M. A. Bishop and F. Li in litt. 2016). There have been conservation and development programmes in local communities at the important sites of Cao Hai and Dashanbao. The Indian breeding population occurs in the Changthang Cold Desert Wildlife Sanctuary. Shooting of cranes and other wildlife in the region has been substantially reduced due to control of firearms, better enforcement of wildlife protection laws and greater awareness (J. Harris in litt. 2007). There is an annual census of the wintering population in Bhutan, where there is also November festivals held to raise public awareness of the importance of crane conservation (Anon. 2010a, b), and annual winter counts at Dashanbao, Cao Hai and Napahai. Education programmes also exist at two key sites in China; Cao Hai and Ruoergai (M. A. Bishop and F. Li in litt. 2016). Winter ecology and migration studies have been conducted extensively in recent years. Winter cropping is banned in Bumdeling, Bhutan, to maintain a food supply for the cranes (Lhendup and Webb 2009).
139 cm. Large, whitish-grey crane. Black head and upper neck apart from whitish postocular patch and red crown patch. Black primaries and secondaries. Similar spp. Common Crane G. grus is smaller, has white stripe from behind eye extending down nape and black primaries, not secondaries. Red-crowned Crane G. japonensis has white primaries and more extensive white area behind eye. Voice Call is high-pitched and penetrating.
Text account compilers
Chan, S., Martin, R.
Contributors
Chan, S., Harris, J., Li, F., Bishop, M., Liu, Q., Chandan, P., Eaton, J., Guo, Y., Allinson, T, Taylor, J., Peet, N., Mahood, S., Khwaja, N., Pilgrim, J., Symes, A., Westrip, J.R.S., Yang, X., Acharja, I., Millington, S., Dhumal, S., Choudhury, A. & Tshering, J.
Recommended citation
BirdLife International (2024) Species factsheet: Black-necked Crane Grus nigricollis. Downloaded from
https://datazone.birdlife.org/species/factsheet/black-necked-crane-grus-nigricollis on 26/12/2024.
Recommended citation for factsheets for more than one species: BirdLife International (2024) IUCN Red List for birds. Downloaded from
https://datazone.birdlife.org/species/search on 26/12/2024.