Geographical Coordinates 52°05’N, 139°48’E
Lower Amur, Khabarovsk Region, Ulchinsky District. The site is located 100 km upstream from the mout of the Amgun River and 500 km downstream of the city
of Khabarovsk. The site is 5 km away from the nearest village of Kolchem and 30 km far from the village of Bogorodskoye (district centre). Im summer there is a water
transport, in winter — ice roads and snowmobile.
Area: 57,600 ha
Altitude: 3-100 m a. s. l.
Ramsar classification - L, M, O, Tp, Ts, U, W
2a, 2с, 2d — the wetland supports populations of rare species, in particular the largest in the Amur region populations of swan goose (Anser cygnoides) and Steller’s
sea eagle (Haliaeetus pelagicus).
1а, 1с — a representative example of typical large wetland of Lower Amur region.
4b — the Udyl basin plays an important role in salmon spawning.
The main is 2а — a pocket of rare species
The site comprises a large freshwater lake and adjacent wet meadows and mires. The area is important for migrating, breeding and moulting populations of waterfowl, including rare and threatened species.
Created on September 13, 1994.
Geology and geomorphology. The site is situated in the Udyl-Kizinsk depression which was formed in the Tertiary. The major portion of the depression is presented by
a lacustrine-alluvial plain with hummocky topography. The steep southwestern and southeastern shores of Lake Udyl are composed of clayey and siliceous shales.
Lake Udyl is a drainage lake, connected with the Amur River by the Ukhta channel which is 35 km long, 30-50 m wide and to 5-6 m deep during the flood period. The open water area comprises about 330 km2 in summer. The highest water level is observed in July-August, and the lowest, in late March. The lake is shallow: the average depth is 2-3 m in summer, with a maximum of 5 m.
The area has a northern-monsoon climate. The Arctic continental air masses dominate in winter. The mean air temperatures are between -24° and -27°C in January and +17.5°C in July. Snow cover is not deep and the grounds freeze down to 2—3 m in winter. Annual precipitation varies between 450 and 480 mm, with 60-64% falling between May and September, and only 40-50 mm from November till March. Most of the unshadowed days are in winter. In February-March snowstorms are common.
Lake Udyl is oblong in shape; it is 50 km long and 5-10 km wide. The Bezymyanny Peninsula with cape Zholmyh divides the lake into two almost equal parts: the southwestern and northeastern ones. There is the narrowest part of the lake (2,5-3 km) between the cape and the mouth of river Bitki. The northeastern shoreline is slightly indented. This shore is low and marshy, and composed of sands and clays. Only 5-6 km far from it there can be seen isolated hills. The southwestern and southeastern shores are precipitous. The lake has almost no aquatic vegetation.
The significance of the region as a place for nesting
The site is very important for conservation of migratory waterbirds, passing through the area in large amounts in spring and in autumn. In 1979, 3,800-4,000 adult geese (without chicks) were counted, including 800-850 birds with broods. The average density of duck nests is 2-3 pairs per km, with a maximum of five pairs.
The significance of the region as a place for rare and threatened species
Lake Udyl and adjacent wetland areas provide important habitats for a number of rare and threatend bird species. The local population of swan goose (Anser cygnoides) was the largest in the USSR in the 1980s. In the 1990s, the numbers have decreased, and only several dozens of pairs breed in the area presently. This species is endemic to the Far East of Russia, that does not nest anywhere else. The local population of Steller’s sea eagle (Haliaeetus pelagicus), an endemic species to the Far Eastern Russia, is the largest in the Amur region. Both species are nesting and breeding in mouths of the rivers that pour into Udyl. Other species encluded in the Russian Federation Red List of Threatened Species include: osprey (Pandion haliaetus), white-tailed eagle (Haliaeetus albicilla), black stork (Ciconia nigra); presumably breeding
species: Baikal teal (Anas formosa), Chinese merganser (Mergus squamatus), Baer’s pochard (Aythya baeri) and Blakiston’s fishowl (Ketupa blakistoni).
The rare forest plants are represented by yewtree (Taxus cuspidata) included in the Russian Federation Red List of Threatened Species, which occurs in its shrub form. The floodplain forests are mainly represented by willow formations dominated by Salix schwerini.
THREATENING AND DISTURBING FACTORS
Pollution of the Amur waters by phenols and other contaminants produces the major threat to the wetland.There is a danger of oil pollution. Rivers, that flow into the lake, are polluted by gold mines. Overfishing has caused a decrease in fish populations. Forest cutting takes place in the catchment of the Bichi River. Also poaching and capture of Steller’s sea eagle for commercial needs increased.
A The site is protected as the Udyl Wildlife Refuge (‘zakaznik’), established in 1988 with area 104400 ha as a zoological reserve and in 1995 upgraded to a wildlife refuge of federal importance and received a status of a wetland of international importance. In 2001 the refuge of local importance was established nearby. There is also a nature monument “Island Krachiy”(Tern Island) with area of 5 ha. In 2016, Udyl Wildlife Refuge with three protected areas were included in “Zapovednoye Priamurye” Joint Directorate of Nature Reserves and National Parks of Khabarovsky Province.