Tso Kar Basin

Country/territory: India

IBA Criteria met: A1 (2004)
For more information about IBA criteria please click here

Area: 10,000 ha

Protection status:

Bombay Natural History Society
Most recent IBA monitoring assessment
Year of assessment Threat score (pressure) Condition score (state) Action score (response)
2013 medium not assessed negligible
For more information about IBA monitoring please click here

Site description
Tso Kar Basin is the basin of a former large freshwater lake (Chatterjee et al. 2002). It lies between the Zanskar range in the southwest and the Ladakh range in the northeast, south of the Indus river. It is called Tsokar, meaning white lake, because of the white salt efflorescence found on the margins due to the evaporation of highly saline water. The waterspread has contracted into two principal waterbodies, Startsapuk Tso, a freshwater lake of about 300 ha to the south, and Tso Kar itself, a hypersaline lake of 2,200 ha to the north. The lakes are frozen over from November to April. Startsapuk-Tso is fed by perennial springs and snow, and attains a maximum depth of 3 m in July and August, when it overflows northwards into Tso Kar. The basin is surrounded by peaks rising to over 6,000 m. The presence of freshwater mollusc Lymnea auricularia fossils proves that it was a freshwater lake in the past (Sharma 2000). The present lake is a remnant of a large freshwater lake of nearly 13,600 ha. In the less saline parts of the basin, the pools have aquatic vegetation including Potamogeton and Hydrilla spp. These plants die in winter, and form floating mats of vegetation in spring. The adjacent freshwater marshes and damp meadows support a mixture of Carex and Ranunculus spp. The arid steppe vegetation of the surrounding areas is dominated by species of Astragalus and Caragana.

Key biodiversity

AVIFAUNA: Tso Kar Basin is one of the most important breeding areas of the Black-necked Crane Grus nigricollis in India (Pfister 1998). O. Pfister (pers. comm. 2003) observed two breeding attempts, one in 1996 near its eastern shore (one egg), and again in 1997 at the northern shore (two eggs), but both nests were flooded due to rising water levels by the end of June. In 2002, a nest with two eggs was found in the northeastern part of Tso Kar Lake, but they were lost due to unknown reasons. A breeding pair near Startsapuktso (freshwater lake in the Tso Kar plains) has been more successful in raising two chicks each in 2000 and 2001, and was found breeding in 2002 also (Pankaj Chandan pers. comm. 2002). This IBA is also the major breeding area for Crested Grebe Podiceps cristatus, Bar-headed Geese Anser indicus, Ruddy Shelduck Tadorna ferruginea, Brown-headed Gull Larus brunnicephalus and Common Tern Sterna hirundo. During autumn migration, the Tso Kar Basin becomes an assembling place for local breeding birds as well as a major staging spot for migrants, and congregations of thousands of birds can be observed.

OTHER KEY FAUNA: Wild Ass Equus kiang and Tibetan Argali Ovis ammon hodgsoni forage on the slopes and meadows, while Tibetan Wolf Canis lupus and Red Fox Vulpes vulpes occur in the surrounding plains. In addition, evidence of the endangered Snow Leopard Uncia uncia has been recorded.

Recommended citation
BirdLife International (2020) Important Bird Areas factsheet: Tso Kar Basin. Downloaded from on 10/07/2020.