Justification of Red List Category
This species is classified as Endangered because it has a very small population, and although the population in Japan has grown, the continental Asian population continues to decline owing to loss and degradation of wetlands through conversion to agriculture and industrial development.
The global population is estimated to number c.3,050 individuals (range 2,800-3,300). Given the opportunities for missing individuals or double counting, three-year averages (for winters 2012-13, 2013-14 and 2014-15 have been calculated: China 580; Korea 1,000, and Hokkaido 1,470. The number of mature individuals is roughly 1,830 (J. Harris in litt. 2016).
The population in Japan has increased but that on the continent is declining due to a number of factors, most importantly the degradation of breeding and wintering sites. Apparent recent increases are likely to reflect increased concentrations at fewer sites, and the global population is thought to have declined by at least 20% over the past 37 years or three generations (J. Harris in litt. 2009).
Grus japonensis breeds in south-eastern Russia, north-east China, Mongolia (where it was first recorded in 2003 [O. Goroshko in litt. 2003]), and eastern Hokkaido, Japan (BirdLife International 2001). The global population is split into continental and island groups, and the continental is split into the eastern flyway and western flyway subpopulations. The eastern population is stable or slightly increasing, whilst the western flyway is severely declining (Su and Zou 2012). The Russian and Chinese populations mainly winter in the Yellow river delta and the coast of Jiangsu province, China, and the Demilitarised Zone, North Korea/South Korea. Staging areas exist along the Yellow river between the provinces of Shanxi and Shaanxi. The Japanese population is non-migratory. Crane census data in the Sanjiang Plain shows numbers to be stable between 1984 and 2008, but with increased concentration to fewer localities due to land use changes (Jiang et al. 2012). Zhalong wetland is an important breeding site within the Songnen Plain (Quian et al. 2012) and the species can also be found breeding on the Russia-China border of the Argun river (Goroshko 2012). Numbers of over wintering cranes in Yancheng National Nature Reserve decreased by 65% between 1999-2000 to 2008-09 (Anon 2013). The global population is estimated at c.2,750 birds; however, this species has a long generation length (12 years), so the population is likely to include only c.1,650 mature individuals (J. Harris in litt. 2007, 2009). Trends are difficult to infer from population estimates, because due to habitat degradation wintering sites are becoming more concentrated and counts are therefore likely to be becoming more accurate, but due to extensive habitat loss it is probably declining on the continent (J. Harris in litt. 2007, 2009). The wintering population in China totals c.400-500 birds (Su and Wang 2010). There are another 1,000-1,050 at four locations in North/South Korea (Lee and Yoo 2010). The resident population in Japan has increased to c.1,470 birds (Red-crowned Crane Conservancy, unpublished data), but this growth is not expected to continue due to habitat limitations and change in winter feeding methods by the Ministry of the Environment, Japan, to reduce high concentrations of cranes.
In Russia and China, it breeds in grass, reed, and sedge marshes. In winter and on passage, it occurs in wetlands, including tidal flats, saltmarshes, rivers, wet grassland, saltpans and aquaculture ponds and in artificial feeding grounds (in Japan). Tidal mudflat crab Helice tientsinensis has been found to be an important food source during migration, alongside smaller numbers of other crab species (Eriocheir sinensis, Macrophthalmus dilatatum), fish and ragworms Hediste diversicolor (Li et al. 2014). It also feeds on croplands, where it is vulnerable to poisons (Y. Momose in litt. 2016). Level of human disturbance and flock size has been found to influence time spent being vigilant by this species wintering in the Yancheng Biosphere Reserve, China (Wang et al. 2011). Landscape and plot level factors are important in explaining crane occurrence, including presence of seepweed tide flats, tamarisk-seepweed tidal flats, reed marshes and other natural wetlands. In the Yellow River Delta Nature Reserve, China, the species was negatively associated with roads (Cao et al. 2015).
The key threat is the loss and degradation of wetlands in its breeding and wintering grounds, principally for conversion to agriculture, but also aquaculture and industrial and economic development (J. Harris in litt. 2007, 2009; Harris and Mirande 2013 in prep). Due to habitat loss, the winter range in China is now only 8% of what it was in the 1980s (Su and Zou 2012). This loss of habitat is leading to the over-concentration of cranes at a few sites (Wang Qi-shan 2008). In China, wetlands are becoming drier as a result of surrounding development (J. Harris in litt. 2007, 2009). In Russia and China, spring fires destroy suitable nesting grounds, and the proliferation of dams lowers water levels, allowing predators access to nests and destroying suitable breeding sites (J. Harris in litt. 2007, 2009). Human disturbance has been so high as to prevent individuals from nesting in some areas (J. Harris in litt. 2009) and has been found to influence vigilance behaviour (Wang et al. 2011). Rainfall patterns in the breeding grounds appear to follow a 30-year cycle, and the current dry period has meant birds, people and livestock have had to depend on ever smaller areas of wetland, also resulting in increased pressure to divert water from rivers and lakes (Harris 2008). Wetland restoration at Zhalong Nature Reserve (China) was recorded as causing inappropriately-timed floods leading to nest failure (Wang and Li 2008). Important sites on the Song-nen plain, Shuangtai Hekou and Yellow River delta are on or near major oilfields and pollution is a potential threat (J. Harris in litt. 2007, 2009). There is high adult mortality in some continental wintering areas which is apparently due to poisoning (Harris and Mirande 2013); the species has been found to carry high levels of heavy metal contamination (Teraoka 2008), and the incidence of poisoning has been increasing in recent years (Harris 2008, Su Liying et al. 2008, Su and Zou 2012, Luo et al. 2016). Future construction of dams on the Amur river and its tributaries is a threat (W, Heim in litt. 2016). Poaching has also been suggested as a threat (Su Liying et al. 2008) and some cranes and their eggs are taken for the captive trade (Su and Zou 2012). In the Demilitarised Zone of North/South Korea, the shift to autumn ploughing is reducing access to waste grain (Lee et al. 2007), and there is great uncertainty regarding the long-term fate of the crane habitat, whatever the political future delivers. Also the DMZ in Korea is under pressure for development due to the recent relaxation of tensions between South and North Korea (Lee et al. 2007b); restrictions on human activities in the adjacent Civilian Control Zone are being eased so that smaller areas are free from agriculture structures and human activity incompatible with cranes (Harris and Mirande in prep). In Japan, the concentration of birds at feeding stations means there is a risk of disease, especially given the low genetic diversity of the population, which passed through a bottleneck in the 1950s (J. Harris in litt. 2007, 2009; Wang Qi-shan 2008).
Conservation Actions Underway
CITES Appendix I and II. CMS Appendix I and II. Part of the European Endangered [Species] Programme of the European Association of Zoos and Aquaria. It is legally protected in all range states. Key protected areas include Khingansky, Muraviovka and Lake Khanka (Russia), Zhalong, Xianghai, Hui River, Shuangtai Hekou, Yellow River delta and Yancheng (China), Kumya and Mundok (North Korea), Kushiro, Akkeshi-Bekanbeushi and Kiritappu (Japan). All cranes surveyed in the Sanjiang Plain region by Jiang et al. (2012) were recorded within one of seven National Nature Reserves, which collectively cover 6994 km2. Surveys of the wintering population in China have been carried out since 2006 (Su Liying et al. 2008). The International Red-crowned Crane Workshop was held in Japan in November 2008, where it was concluded that international cooperation was necessary to stop development from threatening crane habitat across the species's range (Wang Hui 2008, Hu et al. 2009). Artificial feeding has been set up at some sites (Wang Qi-shan 2008).
Conservation Actions Proposed
Identify breeding times during which particularly stringent protection rules should be implemented, as has been done at Liaoning Shuangtai Estuary (Zou Hong-fei et al. 2008). Improve general monitoring procedure, with complete censuses, satellite tracking and aerial counts. Determine Area of Occupancy to a more accurate level. Initiate a study of heavy metal contamination on the mainland (J. Harris in litt. 2009). Expand the area/number of wintering sites in Japan. Establish a transboundary protected area at Tumen estuary, between Russia/China/North Korea. Secure the conservation status of the Cholwon and Han estuary in the Demilitarised Zone. Strengthen management of protected areas on the Sanjiang plain (China), reducing human disturbance. Halt tidal-flat reclamation along the Yancheng coast (China), and control the highly invasive cordgrass Spartina alterniflora. Improve management of wetland restoration at Zhalong, to prevent floods from causing breeding failure (Wang and Li 2008). Prevent poisoning from pesticides and poaching. Control fires in the breeding grounds. Establish interest groups and a communications organisation for crane conservation in China (Wang Qi-shan 2008) and extend captive breeding programmes for future reintroduction and population supplementation.
150 cm. Very large, predominantly white crane. Black face and neck, but with white patch extending from behind eye to nape. Red crown. White primaries and black secondaries and tertials. Similar spp. Siberian Crane G. leucogeranus and Whooping Crane G. americana have black primaries and white necks. Black-necked Crane G. nigricollis has grey body. Voice High-pitched, penetrating calls.
Text account compilers
Benstead, P., Chan, S., Khwaja, N., Mahood, S., Peet, N., Symes, A., Taylor, J., Allinson, T, North, A., Martin, R
Momose, Y., Goroshko, O., Smirenski, S., Parilov, M., Chan, S., Harris, J., Lee, S., Li, Z.
BirdLife International (2021) Species factsheet: Grus japonensis. Downloaded from http://www.birdlife.org on 06/03/2021. Recommended citation for factsheets for more than one species: BirdLife International (2021) IUCN Red List for birds. Downloaded from http://www.birdlife.org on 06/03/2021.