Inga Bysykatova-Harmey.
Candidate of Biological Sciences, researcher, Laboratory of Zoological Research, Institute for Biological Problems of Cryolithozone SB RAS.
Email: ipbysykatova@gmail.com

On the current status of the Siberian crane (Leucogeranus leucogeranus)

Being the third rarest species of cranes in the world, the Siberian crane is included in the IUCN Red List of Threatened Animals as a critically endangered species.
The species is included in the Red Data Books of the USSR, the Russian Federation, the Sakha Republic (Yakutia), CITES Appendix (1a) and other national and regional lists of rare animals; protected under the Ramsar and Bonn Conventions.
The Siberian crane nests only on the territory of Russia, forming two scattered populations: the almost disappeared West Siberian one (Ob), inhabiting the marsh areas of the northern taiga larch forests of Tyumen Oblast and wintering in Iran, the East Siberian one (Yakut), relatively prosperous, inhabiting the typical lowlands tundra between the Yana and Kolyma Rivers in the northeast of Yakutia and migrating to winter in southeastern China. While the number of Siberian cranes in Western Siberia hardly exceeds 20 birds, northeastern Yakutia welcomes about 3,500 individuals for nesting.

Fig. 1. The maps of western, central and eastern migration routes of the Siberian crane.

Currently, the Yakut population nesting area lies in the subarctic tundra of the Yana and Kolyma interfluve eat and west of the Indigirka River between 69-70 parallel north.

Fig. 2. The nesting area model of the eastern population of the Siberian Crane:
I – nesting area (720 thousand km2);
II: A – the area of regular nesting (590 thousand km2); B – the area of increased density (263 thousand km2); C – the area of irregular sporadic nesting;
III: the boundaries of the Siberian crane range according to A.G. Degtyarev and Yu.V. Labutin (1991), A – the area of regular habitation; B, C, D – the areas of increased density of the Siberian crane

Photo by Rob Belterman. A Siberian crane chick with its parents.

Siberian cranes prefer to nest on sedge-cottongrass bogs in the lakeside lowlands and interlake depressions, where they find the most optimal feeding and nest-friendly conditions. 6 Birds avoid dry hummocky elevations with the moss-lichen and dwarf birch cover. The most characteristic nesting habitats are vast (about 5 km2) shallow lakeside depressions, sometimes with a well-pronounced polygonal structure, overgrown with low sparse sedge and cotton grass. The water depth in such lowlands does not exceed 25-50 cm.

Fig. 3. The optimal Siberian crane habitat – sedge and sedge-cottongrass bogs in lakeside lowlands and interlake depressions (А, Б).

Photo by Inga Bysyskatova-Harmey. A Siberian crane near the Sundrun River, Allaikhovsky District, Yakutia.

Photo by Inga Bysyskatova-Harmey. A Siberian crane chick in the lake, Allaikhovsky District.

Photo by Inga Bysyskatova-Harmey.

Photo by Inga Bysyskatova-Harmey. A pair of Siberian cranes with a chick.

Photo by Inga Bysyskatova-Harmey. A pair of Siberians crane near the Sundrun River, Allaikhovsky District.

Photo by S.B. Rosenfeld. A group of Siberian cranes in the tundra, Allaikhovsky District.

Yakutia, mainly in the Trans-Baikal Territory. Outside of Russia, the largest number of non-breeding Siberian cranes of the eastern population are seen in boggy lowlands of the forest and forest-steppe zones of Mongolia in summer.

Fig. 4. Summer residences of non-breeding birds outside Yakutia:
1 – в Красноярском крае (Черников, 1988; Ro-gacheva, 1992);
2 – в Хакасии (Sushkin, 1914);
3 – в Иркутской области (Нау-мов, 1979); в Забайкальском крае:
4 – in the 1990s, 5 – in the period 2007- 2011. (Goroshko, 1998, 2011; Malkov, 2011); in Mongolia:
6 – с 1980 по 1990 гг.,
7 – in the period 2000-2010. (Ostapenko, Tseveenmyadag, 1988; Bold, Zvonov, Tseveenmyadag, 2004; Tseveenmyadag, 2006, 2008, 2011)
8 – в Приморском крае и Амурской области в 2007 г. (Парилов, 2006; Антонов, Парилов, 2009); 9 – встреча стерха в 1987 г. на Камчатском п-ве (Моисеев, Токранов, 2000)

Photo by Tseveenmyadag Natsasdorj. Young Siberian cranes in Mongolia.

With the total migration length of about 6,500 km, the migration period of the Siberian crane in Yakutia last for over a month.
In northeastern China, the transit stops of the Siberian crane are much longer, and the concentrations of birds are more numerous than in Russia. To a certain extent, this is due to the intensive use and reclaiming of wetlands and, thus, the disappearance of usual habitats suitable 10 for resting of migrating cranes. As a result, birds fly non-stop over longer distances and rest longer in every available location.

Photo by I.A. Ayanitov. A Siberian crane during the spring migration near the village of Maya, central Yakutia.

Photo by A.G. Sorokoumova. Siberian cranes during the autumn migration in Abyisky District, Yakutia.

During the migration period, the Siberian crane is found in many areas of eastern Yakutia, and recently – more and more often in the western part of the region – east of the Lena River.
During the migration period, the Siberian crane is found in many areas of eastern Yakutia, and recently – more and more often in the western part of the region – east of the Lena River. The main spring-autumn migration routes of the cranes run in the east of the region. They usually follow the valleys of big rivers – Yana, Indigirka, Alazeya and Kolyma (before the sharp turn of 11 the river to the east, 650 N). The migration of Siberian cranes in Yakutia takes place in a narrow corridor, being most intensive in the Middle Aldan valley. At some observation points here, they visually register up to 5.5% of the entire population in spring, and up to 60% in autumn. Outside Yakutia, Siberian cranes have been seen on migration in the southern part of
Amur region, in the Zeya basin and in Primorye (Lake Khanka).

Fig. 5. Encounters with Siberian cranes during migration on the territory of Yakutia, adjacent Russian regions and northeastern China (according to our own observations, literature and questionnaire information, data of satellite tracking of 15 Siberian cranes (9 ad, 4 sad and 2 juv).
The satellite tracking of autumn migrations of adults (10 ad + 6 sad) Siberian crane individuals in 1995-1996 identified 8 main places of their short-term and long-term stops in Yakutia and adjacent regions (Fig. 5, A), and in China (Qiqihar Baicheng, Amannykan, Shuangtaizi River Delta, Yellow River Delta) (Fig. 5, B).

Рис.6. А – Основные для сохранения стерха территории на путях миграции:

1 – a section of the Indigirka River wide valley with the right bank of the lower section of its tributary Allaikha, northeast of the village of Olenegorsk (Allaikhovsky District);
2 – озерные системы в нижнем течении рек Уяндина, Дружины и Куберганэ в левобережной части бассейна р. Индигирка (Аллаиховский и Абыйский районы);
3 – предгорья хребта Черского (юг Абыйской низменности): бассейны рек Куранных, Холболоох, Берелех (Момский район);
4 – Эльгинское плоскогорье – бассейн верховья р. Эльга: крайняя западная точка оз. Делиньи, на востоке – левый берег р. Утачан (граница Томпонского и Оймяконского улусов);
5 – предгорье Верхоянского хребта: р. Хандыга на западе – р. Томпо на востоке (Томпонский район); 6 – бассейн среднего течения р. Алдан (Таттинский, Чурапчинский, Амгинский, Усть-Майский районы); 7 – долина среднего течения р. Алгома (Нерюнгринский район);
8 – Зейское водохранилище (Амурская область)
Б. The network of protected areas along the migration routes of the Siberian crane in China.
The main wintering area of the population (99%), which has been known since 1980, is located in the lake system of the Poyang Nature Reserve in the basin of the middle reaches of the Changjiang (Yangtze) River in southeastern China (29°N and 116°E); small groups of the population winter on Lake Dongting, Hunan Province. The wintering period lasts from mid- November to mid- March. From April to July, a significant part of the reserve and its environs is flooded and the winter network of lakes is represented by Lake Poyang, only, with the depth reaching 21 meters and the area of 4 thousand square kilometers. In winter, the water level in the lake drops, forming a large number of smaller lakes and ponds, wet meadows, and sandbanks. By the mid-winter, 9 main lakes remain in the reserve, the largest of them being Taiza Hu, Dahu Chi 13 and Bang Hu. Under 100 individuals spend the winter at Lake Dong Ting in Hunan Province. Perhaps, there are other wintering sites that are currently unknown.

Photo by Inga Bysykatova-Harmey. Siberian cranes on Lake Poyang.

Photo by Zheng Zhonjie. Siberian cranes on Lake Poyang

Фото Zheng Zhonjie. Семья стерхов на озере Поянг

Fig. 7. The seasonal variations of the Lake Poyang water levels (May, July, 2007) (Source: russian.china.org.cn).

While the total number of Siberian cranes wintering in China in the early 1980s numbered to tens to hundreds of birds, there were already thousands of individuals in the late 1980s: from 1,482 in 1985/1986 to 2,653 in 1998/1999.
The dynamics of the population at the nesting site can be seen from the results of five largest-scale surveys, which covered, more or less evenly, the area of the regular habitat: in 1980, the number of cranes was estimated as 810 individuals, in 1985 – as 670, in 1989 – as 870, in 1994 – as 988, and in 1995 – as 1,500 birds.
At present, the main limiting factor in the nesting area for the cranes is the fact that they are disturbed by waterfowl and mammoth bone hunters. Tracked vehicles getting to hard-toreach places, including the areas of the Siberian Crane intensive reproduction, contribute to the process of delichenization of the tundra, soil erosion, and replacement of the lichen cover with herbaceous one. The Siberian crane is a distant migrant, which suggests an increased vulnerability of the population. The time of its migrations coincides with the opening of the fishing and hunting seasons, which increases the likelihood of unwanted encounters with humans.
The territorial protection of the Siberian crane, as well as other rare and endangered bird species, during their nesting period in the subarctic tundra of northeastern Yakutia and during migrations, is carried out in Yakutia at 19 functioning protected areas of various ranks.
In terms of the population conservation, the most significant of them are the Kytalyk National Park, created in December 2019, and Chaigurgino, Kuoluma, Kuoluma-Chappanda, Kyupsky, and Chabda Sakha republic’s resource reserves. The Kytalyk National Park and Chaigurgino Resource Reserve host a significant part of the Siberian crane population; their migration is most intensive in the middle-taiga protected areas located in the Aldan basin.
On the territory of China, a threat during the wintering period on Lake Poyang comes from the world's largest hydroelectric power station "Three Gorges", built in the upper reaches of the Changjiang River. Before the construction of the dam, the Changjiang River and its 15 tributaries, eroding the banks, carried millions of tons of sediment annually. Due to the construction of the dam, their removal will be significantly reduced, which may change the hydrological regime of the Changjiang River and lead to the loss of traditional waterfowl wintering sites. Another big threat to the Siberian crane at the sites of migration and transit stops in China is the deterioration of the state of wetlands, due to unregulated water intake for agricultural purposes.
In China, the main key habitats for the population are maintained at 13 reserves. At places of intensive migration and large transit stops, these are the reserves Dalai Lake (Inner Mongolia), Tumuji (Inner Mongolia), Keerqin (Inner Mongolia), Momoge (Jilin), Xianghai (Jilin), Zhalong (Heilongjiang), Shuangtaihekou (Liaoning), Yellow River Delta (Shandong), Yancheng (Jiangsu), Anqing Yanjiang (Anhi), Shengjinhu (Anhui); at wintering places – Dongting Lake (Hunan) and Poyang (Jiangxi).
In Mongolia, where the number of "summering" Siberian cranes is growing, in the places where the cranes are seen, there is the Mongol Daguur Reserve of international importance, Onon-Baldzhinsky National Park, and Dornod Mongol Nature Reserve.
Thus, the current status of the Yakut population of the Siberian crane is assessed as quite safe. In the past twenty years, the dynamics
of its population number has been showing a steady positive trend, which can be traced both at wintering sites and migration routes, transit stops and nesting sites. The population demonstrates a desire to expand the range in the northwest direction. The geography of encounters has expanded, and the frequency of seeing the birds beyond the previously known boundaries of their population range has increased. Of course, this is the result of environmental measures taken in the countries where the population is spread, related to the conservation of the Siberian crane and its habitats, as well as increased environmental awareness of the human population.

The bibliography:
1. Birdlife International. Threatened Birds of Asia: the Birdlife International Red Data Book / Birdlife International // 2 vols. Ed. N.J. Collar. Cambridge, UK: Birdlife International. – 2001. P. 1090-1117.
2. Bysykatova I.P., Krapu G.L., Germogenov N.I. Densities, habitat use, andsocial status of Siberian cranes in the Khroma river region of Northern Yakutia /I.P. Bysykatova, G.L. Krapu, N.I. Germogenov // 12th North American Crane Workshop. – Nebraska, USA, 2012. – P. 30.
3.Bysykatova I.P. The current state of the Yakutian populations of tundra species of cranes. LAP LAMBERT Academic Publishing, 2016. 264 p.
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5. Germogenov, N.I., Solomonov, N.G., Pshennikov, A.E., Degtyarev, A.G., Sleptsov, S.M., Egorov, N.N., Bysykatova I.P., Vladimirtseva M.V., Okoneshnikov, B.V. Eastern population of Siberian crane: structure, habitats, nesting and migration / XX International Congress of Zoology. – 2008. – P. 7.
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