Habitat ecology and conservation status of wild ungulates in Northern parts of Changthang Wildlife Sanctuary, Ladakh

Abstract

An ecological study on the wild ungulates was carried out in the northern parts of Changthang Wildlife Sanctuary, Ladakh during 2007 – 2009 with a view to ascertain the population status, distribution and habitat use pattern. The five species of sympatric ungulates found in this part of Trans-Himalaya include chiru or Tibetan antelope (Pantholops hodgsoni), wild yak (Bos mutus), Tibetan argali (Ovis ammon), kiang (Equus kiang) and blue sheep (Pseudois nayaur). Specific objectives of the study were: (i) To study the population status and distribution of wild ungulates in northern parts of Changthang WLS, (ii) To study the habitat characteristics and habitat use by the ungulates, (iii) To identify the major threats and suggest conservation strategies, and (iv) To evolve protocol for monitoring wildlife populations in the study area. 2.The study area was located in the north and north-east of Pangong Tso covering Phobrang surrounds and Changchenmo Valley which vary in altitude from 4450 to 5800m asl. The entire landscape is spread over an area of >3100 km2. However, intensive study was conducted within <500 km2 around Phobrang and Changchenmo. The study area is characterized by cold arid environment with very sparse vegetation cover which can be categorized into moist and mixed meadows, desert steppe and scrub steppe. About 12% geographical area is covered by perpetual snow and glaciers, 1.6% area is represented by moist and marsh meadows and over 84% area is under sparsely vegetated desert steppe which is further divisible into various landscape units and habitat types. The study area is the only place within Indian territory where these five sympatric ungulates co-exist.3.Based on a reconnaissance trip we classified the study area into various strata. Field work was carried out during 2007 – 2009 covering two summer and one winter season. Line Transects and trail monitoring were followed for the collection of data on population structure, status and distribution of ungulates in various areas on seasonal basis. In each strata transects varying in length of 6-8 kms were walked. A total of 503 km were monitored in 42 trails, spending 249.85 hrs of observation. Data based on direct sightings and indirect evidences of ungulate species were recorded along transects in the survey blocks. Habitat parameters were quantified using standard methods. Conservation and management issues were identified based on primary and secondary data collected from the survey area.4.The study reveals that of the five species of sympatric ungulates, chiru and wild yak use only parts of Changchenmo Valley while remaining three species are found in both the areas. In Changchenmo Valley we estimate a population of 20 – 30 chiru, 110 – 120 wild yak, 125 – 150 kiang, 120 - 130 blue sheep and 35 – 50 Tibetan argali. Based on the past reports and present study we conclude that number of chiru population in Changchenmo Valley is on decline. Our study reveals that chiru males do use Changchenmo Valley during winter. For the first time, we report a new location of chiru i.e., Thratsang La in Changthang plateau.5.Blue sheep, being smallest of all the ungulates, selected steep and glaciated zones with short forbs and a few graminoids. Chiru males and wild yak were confined to eastern part of Changchenmo Valley, especially with higher cover of graminoids (Carex moorcroftii, Stipa purpurea, Leymus secalinus and Scirpus sp.). Kiang occupied most of the habitat categories except steep slopes and cliffs. Highest altitudes were used by blue sheep followed by wild yak, Tibetan argali, chiru and kiang. Kiang and argali showed preference for south facing slopes while other species used in proportion to availability.The major conservation issues in the study area include (i) Small and fragmented populations of threatened ungulates, (ii) Degradation of rangelands and loss of productivity, (iii) Possible genetic contamination of wild yak, (iv) Presence of feral dogs around security camps, (v) Lack of alternate livelihoods for the local people, (vi) Inadequate infra-structure and man power for the PA management. Appropriate recommendations to deal with above issues have been given.The study area is partly controlled by the Indian security personnel, who have taken keen interest in the conservation and monitoring of threatened wildlife in the area. A detailed monitoring protocol based on vehicle survey, on-foot patrol and animal observations from the fixed positions have been suggested.