Surface area: 32.700 ha
Elevation: 1.133-1.751m

Protection status: Partially protected by Bulgan River Nature Reserve.

Site description: The Bulgan River originates in the Mongol Altai high mountains, flows into Ulungur Lake of China. Watercourse of Bulgan River divides into large and small streams, forming islands and isolated water bodies. The river runs through semi-desert area and it has a spectacular view with dense reeds, aspen, bushes and meadows, because this is the largest part of Altai Mountains foothill with high moisture level. There are numerous bays, such as Tsagaan Ereg, Sanjiin Tohoi, Balar Tohoi and Elst Tohoi, with dense reeds and shrubs.

Importance for birds: Bulgan river basin is rich with sparrows and raptors and it is an important area for waterbirds and shorebirds that stopover here during migration. Globally threatened bird species Swan Goose (Anser cygnoides), Eastern Imperial Eagle (Aquila heliaca) and Lesser Kestrel (Falco naumanni) occur, exceeding 1% of their flyway populations.

Special flora and fauna: Asian Beaver (Castor fiber) considered in danger of extinction throughout Mongolia, is abundant in Bulgan river basin, thus the reintroduction of Asian Beaver to the other rivers was carried out from Bulgan river. Construction work of hydroelectric dam in the Chinese section of Bulgan River, creating a barrier to migration of wildlife and causing habitat fragmentation along the river.