A wetland refuge on the Russian-Mongolian border
Editor’s note: This story was originally published on June 9, 2021
The ever-changing Torey Lakes are a wetland paradise. Two large lakes and over 300 smaller water bodies in the Torey Depression are home to 305 species of birds and 42 species of mammals, as well as reptiles, amphibians, fish, and over 590 species of insects. Many of them are rare and endangered, and endemic to the region.
Located in Russia, on the border of eastern Mongolia, the lakes are an important stopover for migrating birds.
Tundra Swans rest and feed at Lake Ukshinda in the Torey Depression during their migration north to their nesting grounds. Wetlands in Dauria landscapes are resting places along the East Asian-Australasian flyway. There are up to 3 million migratory birds here in spring and 6 million in autumn (Image: Oleg Goroshko)
A male White-naped Crane feeds near his nest at Lake Lebedinoe, a small steppe body of water in the Torey Depression. With fewer than 8,000 individuals, the species is classified as vulnerable, mainly due to loss of wetlands. This makes Torey Lakes an important nesting ground (Image: Oleg Goroshko)
Rare migratory swan geese forage in their breeding habitats on the lower Ulz River. They return to Mongolia, northern China and southeastern Russia in April for the breeding season (Image: Oleg Goroshko)
JThis is the second in a two-part series on Mongolia’s Blue Horse water infrastructure program. Read the first article here
The Torey Lakes are at the heart of the landscapes of Dauria, a cross-border area straddling Russia and Mongolia. In 2017, it was inscribed on the UNESCO World Heritage List, as “an outstanding example of the Daurian steppe ecosystem”. Covering more than 9,000 square kilometres, its steppe landscapes are connected by the tiny Ulz River, which feeds wetlands and lakes.
View of the Ulz River from the Eltrud Hills, a section of the Dornod Mongol Strictly Protected Area in eastern Mongolia (Image: Vadim Kirilyuk)
Drought and flood
The Dauria steppe has distinct wet and dry periods. Every 25 to 40 years, the Ulz River floods and fills the Torey Lakes. Then, over the years, the lakes dry up until they are filled again. This force shapes the ecosystems and people of the region.
At the height of the wet phase, thousands of ephemeral lakes appear across the steppe. Floodwaters trigger a new cycle of life and provide habitat for a wide variety of life.
Smaller and more frequent floods support central areas. Dauria’s most stable floodplain wetlands are life support systems for wildlife and humans through all phases of the climate cycle. The last filling of the Torey Lakes by the Ulz began in the fall of 2020.
Waterfowl from Lake Zun-Torey in the summer of 2006 come to feed from nearby Lake Barun-Torey. The lake was in the beginning of the drying phase but the water level was still high. Zun-Torey is in the Russian part of Dauria Landscapes (Image: Tatiana Tkachuk)
At the same place in the summer of 2017, a young Mongolian gazelle crosses the dry bottom of Lake Zun-Torey. Gazelles come to the bottom of Torey Lakes to feed on grass and rest, as the moist ground is cooler. As of 2017, a shallow pool of water remained in Zun-Torey; the following year it had completely dried up (Image: Tatiana Tkachuk)
During the dry phase, all small rivers, most springs and up to 98% of lakes disappear. The Torey Lakes take about two decades to completely dry up and are refilled by flooding from the Ulz River after several consecutive years of high water. These “pulsating” water masses create a dynamic mosaic of biodiversity-rich habitats. Wildlife migrates and changes with the fluctuating landscape.
The dry bottom of Lake Zun-Torey in late fall 2020. This area of the lake dried up about three years ago. Mineralized groundwater is still close to the surface and when it evaporates, it leaves behind a white crust of salts. The only plant species that still grows here is adapted to saline or alkaline soils (Image: Tatiana Tkachuk)
Dead silver carp on the shore of Lake Zun-Torey in 2004, at the start of another drought. Every 25 to 40 years, the Torey Lakes shrink and salinity levels exceed what fish can tolerate. Fish die en masse until the next wet period. Local people are encouraged to fish in the Dauria Landscapes buffer zone to make the most of this rare wealth. (Photo: Oleg Korsun)
A spring in the Toson-Khulstai Nature Reserve, Mongolia. Designated as a holy place, it is fenced off to prevent cattle from trampling it. Many marshy areas of the Ulz River and its tributaries are thus fenced off. (Photo: Vadim Kirilyuk)
Threat of infrastructure projects
The region’s future as a biodiversity hotspot is by no means assured. The Ulz basin management plan proposes the construction of reservoirs for agriculture and “environmental needs”. It was supported by the United Nations Development Program and a $5.5 million grant from the Adaptation Fund, which funds projects that help developing countries adapt to climate change.
In response, the Russian-Mongolian Commission for Environmental Cooperation, which oversees cooperation on environmental protection agreements, said maintaining the natural fluctuation of the water cycle is key to preserving the site. of world heritage. Objections to early dam plans were also voiced at working meetings of the Dauria International Protected Area, a 25-year-old trilateral coordination mechanism between China, Russia and Mongolia that brings together research, monitoring, education and other activities for the Darusky, Mogol- Daguur and Hulun (Dalai) Protected Areas.
A hare forages in a meadow at the dry Lake Barun-Torey in 2013. This part of the lake had been dry since at least 2005, allowing sedges and flowering plants to take root. The appearance of certain types of grasses marks the transformation from grassland to steppe (Image: Tatiana Tkachuk)
Nevertheless, in 2020 Sh. Myagmar, head of the Mongolian Water Authority, said: “The first thing we are implementing is to restore the flow of the Ulz River, which dried up during the last decade. Ulz is included in the Blue Horse Program: Mongolia’s National Master Plan for Water Infrastructure Development.
Note: The Blue Horse program has not been published. This map is based on a variety of sources and the expertise of the author; it identifies likely potential locations for dams
In the summer of 2020, the construction of a dam on the Ulz River upstream of the World Heritage Site began.
The reservoir will hold 27 million cubic meters of water. This represents 20% of the average annual flow of the river and more than five times the annual flow during the dry phase of its cycle. Evaporation from the reservoir could mean that 7 to 9 million cubic meters of water are lost each year, which will significantly reduce the flow in dry years.
The Mongolian government began construction without notifying neighboring Russia or submitting a transboundary heritage impact assessment to the UNESCO World Heritage Center. This violates bilateral treaties and key requirements of the Ramsar and World Heritage conventions. The Third Pole invited the Permanent Delegation of Mongolia to UNESCO to comment on these concerns; no response had been received up to the time of publication.
The declared aim of the project is to support the ecological flow of the river Ulz. But the forces of nature, during the current phase of the water-rich climate cycle, will naturally restore the flow. This fact was fully acknowledged in Mongolia’s submission to UNESCO in April 2021.
When the dry phase arrives, the dam project may degrade key habitats and prevent the successful breeding of endangered wetland species, such as the white-naped crane, swan goose and relict gull.
In 2020, the International Union for Conservation of Nature assessed the conservation prospects of the Dauria landscapes. It concluded that the construction of a dam on the Ulz River upstream of the site “is potentially a very serious threat to the natural water regime and the integrity of the habitat of the main wetlands”. He said an environmental impact assessment was urgently needed.
A shepherd in the Russian steppe in the Landscapes of Dauria. Grazing herds depend on the availability of water and grass. The dam upstream of the protected area could cause the Ulz to dry up earlier in the dry phase of the climate cycle. This would worsen conditions for herders during the most critical time when resources are scarce, disrupting the livelihoods of local people (Image: Anastasia Kirilyuk)